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&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Celsion
Corporation (&#x201c;Celsion&#x201d; and the &#x201c;Company&#x201d;) is a fully integrated, clinical stage biotechnology company focused
on advancing a portfolio of innovative treatments including DNA-based immunotherapies, next generation vaccines and directed chemotherapies
through clinical trials and eventual commercialization. The Company&#x2019;s product pipeline includes GEN-1, a DNA-based immunotherapy
for the localized treatment of ovarian cancer and ThermoDox&lt;sup&gt;&#xae;&lt;/sup&gt;, a proprietary heat-activated liposomal encapsulation of
doxorubicin, currently under investigator-sponsored development for several cancer indications. Celsion has two feasibility stage platform
technologies for the development of novel nucleic acid-based immunotherapies and next generation vaccines and other anti-cancer DNA or
RNA therapies. Both are novel synthetic, non-viral vectors with demonstrated capability in nucleic acid cellular transfection.&lt;/span&gt;&lt;/p&gt;

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&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
accompanying unaudited condensed consolidated financial statements, which include the accounts of the Company and its wholly owned subsidiaries,
CLSN Laboratories, Inc. and Celsion, GmbH, have been prepared in accordance with generally accepted accounting principles
in the United States (GAAP) for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X.
All significant intercompany balances and transactions have been eliminated in consolidation. Certain information and disclosures normally
included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;In
the opinion of management, all adjustments, consisting only of normal recurring accruals considered necessary for a fair presentation,
have been included in the accompanying unaudited condensed consolidated financial statements. Operating results for the three and six-month
periods June 30, 2021 and 2020 are not necessarily indicative of the results that may be expected for any other interim period(s)
or for any full year. For further information, refer to the financial statements and notes thereto included in the Company&#x2019;s Annual
Report on Form 10-K for the fiscal year ended December 31, 2020 filed with the Securities and Exchange Commission (SEC) on March 19,
2021.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
preparation of financial statements in conformity with GAAP requires management to make judgments, estimates, and assumptions that affect
the amount reported in the Company&#x2019;s financial statements and accompanying notes. Actual results could differ materially from those
estimates. Events and conditions arising subsequent to the most recent balance sheet date have been evaluated for their possible impact
on the financial statements and accompanying notes. The Company continues to monitor the impact of the COVID-19 pandemic on its financial
condition and results of operations, along with the valuation of its long-term assets, intangible assets, and goodwill. The effect of
this matter could potentially have an impact on the valuation of such assets in the future. The COVID-19 pandemic is discussed in more
detail in Note 3 to the financial statements.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

</us-gaap:BasisOfAccounting>
    <us-gaap:SubstantialDoubtAboutGoingConcernTextBlock contextRef="From2021-01-01to2021-06-30">&lt;p id="xdx_807_eus-gaap--SubstantialDoubtAboutGoingConcernTextBlock_zv4RrF6zTDT7" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
3. &lt;span id="xdx_821_zcInolR5nAVk"&gt;Financial Condition and Business Plan&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Since
inception, the Company has incurred substantial operating losses, principally from expenses associated with the Company&#x2019;s research
and development programs, clinical trials conducted in connection with the Company&#x2019;s product candidates, and applications and submissions
to the U.S. Food and Drug Administration. The Company has not generated significant revenue and has incurred significant net losses in
each year since our inception. As of June 30, 2021, the Company has incurred approximately $&lt;span id="xdx_90D_eus-gaap--RetainedEarningsAccumulatedDeficit_iNI_pn6n6_di_c20210630_ztG3Q0nMBMe1"&gt;323
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million of cumulative net losses and had approximately
$&lt;span id="xdx_90D_ecustom--CashAndCashEquivalentsRestrictedCashShorttermInvestmentsAndReceivableOnSaleOfNetOperatingLosses_iI_pn5n6_c20210630_zk4bgIWIquY2"&gt;64.5
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million in cash and cash equivalents, restricted
cash, short-term investments and interest receivable. We have substantial future capital requirements to continue our research
and development activities and advance our product candidates through various development stages. The Company believes these expenditures
are essential for the commercialization of its technologies.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
Company expects its operating losses to continue for the foreseeable future as it continues its product development efforts, and when
it undertakes marketing and sales activities. The Company&#x2019;s ability to achieve profitability is dependent upon its ability to obtain
governmental approvals, manufacture, and market and sell its product candidates. There can be no assurance that the Company will be able
to commercialize its technology successfully or that profitability will ever be achieved. The operating results of the Company have fluctuated
significantly in the past.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;




&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;In
January 2020, the WHO declared an outbreak of coronavirus, COVID-19, to be a &#x201c;Public Health Emergency of International Concern,&#x201d;
and the U.S. Department of Health and Human Services declared a public health emergency to aid the U.S. healthcare community in responding
to COVID-19. This virus has spread to over 100 countries, including the U.S. Governments and businesses around the world have taken unprecedented
actions to mitigate the spread of COVID-19, including, but not limited to, shelter-in-place orders, quarantines, significant restrictions
on travel, as well as restrictions that prohibit many employees from going to work. Uncertainty with respect to the economic impacts
of the pandemic has introduced significant volatility in the financial markets. The Company did not observe significant impacts on its
business or results of operations during 2020 and into 2021 due to COVID-19. While the extent to which COVID-19 impacts the Company&#x2019;s
future results will depend on future developments, the pandemic and associated economic impacts could result in a material impact to
the Company&#x2019;s future financial condition, results of operations and cash flows. The Company&#x2019;s ability to raise additional
capital may be adversely impacted by potential worsening global economic conditions and the recent disruptions to, and volatility in,
financial markets in the U.S. and worldwide resulting from the ongoing COVID-19 pandemic. The disruptions caused by COVID-19 may also
disrupt the clinical trials process and enrolment of patients. This may delay commercialization efforts. The Company continues to monitor
its operating activities in light of these events. The specific impact, if any, is not readily determinable as of the date of these financial
statements.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
actual amount of funds the Company will need to operate is subject to many factors, some of which are beyond the Company&#x2019;s control.
These factors include the following:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 0.5in; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#x25cf;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;the
    progress of research activities;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#x25cf;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;the
    number and scope of research programs;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#x25cf;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;the
    progress of preclinical and clinical development activities;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#x25cf;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;the
    progress of the development efforts of parties with whom the Company has entered into research and development agreements;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#x25cf;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;the
    costs associated with additional clinical trials of product candidates;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#x25cf;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;the
    ability to maintain current research and development licensing arrangements and to establish new research and development and licensing
    arrangements;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#x25cf;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;the
    ability to achieve milestones under licensing arrangements;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#x25cf;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;the
    costs involved in prosecuting and enforcing patent claims and other intellectual property rights; and&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#x25cf;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;the
    costs and timing of regulatory approvals.&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;
&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
July 13, 2020, the Company announced that it has received a recommendation from the independent DMC to consider stopping the global Phase
III OPTIMA Study of ThermoDox&lt;sup&gt;&#xae; &lt;/sup&gt;in combination with RFA for the treatment of HCC, or primary liver cancer. The recommendation
was made following the second pre-planned interim safety and efficacy analysis by the DMC on July 9, 2020. The DMC&#x2019;s analysis found
that the pre-specified boundary for stopping the trial for futility of 0.900 was crossed with an actual value of 0.903. The Company followed
the advice of the DMC and considered its options to either stop the study or continue to follow patients after a thorough review of the
data, and an evaluation of the probability of success. On February 11, 2021, the Company issued a letter to shareholders stating that
the Company was notifying all clinical sites to discontinue following patients in the OPTIMA Study.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;During
2020, 2019 and 2018, the Company submitted applications to sell a portion of the Company&#x2019;s State of New Jersey net operating losses
as part of the Technology Business Tax Certificate Program sponsored by The New Jersey Economic Development Authority. Under the program,
emerging biotechnology companies with unused NOLs and unused research and development credits are allowed to sell these benefits to other
New Jersey-based companies. In 2018 and 2019, the Company sold NOLs totaling $&lt;span id="xdx_904_ecustom--NetProceedsFromSaleOfNetOperatingLosses_pn6n6_c20180101__20181231__srt--StatementGeographicalAxis__custom--NJMember_zHT2zFu4X2nj"&gt;13
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million receiving net proceeds of $&lt;span id="xdx_90B_ecustom--NetProceedsFromSaleOfNetOperatingLosses_pn5n6_c20190101__20191231__srt--StatementGeographicalAxis__custom--NJMember_z5oV6bjqj5ne"&gt;12.2
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million. In June 2020 and as updated in September
2020, the Company filed an application with the New Jersey Economic Development Authority to sell substantially all of its remaining
State of New Jersey net operating losses totaling $&lt;span id="xdx_90C_ecustom--NetProceedsFromSaleOfNetOperatingLosses_pn5n6_c20200901__20200930__srt--StatementGeographicalAxis__custom--NJMember_zpaYoC4lW2z3"&gt;2.0
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million available under the program. On February
12, 2021, the New Jersey Economic Development Authority approved the full amount of the Company&#x2019;s application. In February of 2021,
the Company entered into an agreement to sell the net operating losses from the 2020 application and the Company received net proceeds
of approximately $&lt;span id="xdx_90E_ecustom--ReceivableOnSaleOfNetOperatingLosses_iI_pn4n6_c20210630_zGqiWGHT1ncg"&gt;1.85&lt;/span&gt;&lt;/span&gt;
&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million on May 10, 2021. During 2021, the New Jersey State
Legislature increased the maximum lifetime benefit per company from $&lt;span id="xdx_90C_ecustom--NetProceedsFromSaleOfNetOperatingLosses_pn6n6_c20210509__20210510__srt--StatementGeographicalAxis__custom--NJMember__srt--RangeAxis__srt--MinimumMember_zyDmUzUgjYo1"&gt;15
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million to $&lt;span id="xdx_90E_ecustom--NetProceedsFromSaleOfNetOperatingLosses_pn6n6_c20210509__20210510__srt--StatementGeographicalAxis__custom--NJMember__srt--RangeAxis__srt--MaximumMember_zTnGwnQ5wTN7"&gt;20
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million, which will allow the Company to participate
in this innovative funding program in future years. On June 16, 2021, the Company filed another application to sell approximately $&lt;span id="xdx_903_ecustom--NetProceedsFromSaleOfNetOperatingLosses_pn5n6_c20210615__20210616__srt--StatementGeographicalAxis__custom--NJMember_zOrlede95sDf"&gt;1.6
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million of net operating losses during 2021
and expects to receive up to approximately $&lt;span id="xdx_908_ecustom--NetProceedsFromSaleOfNetOperatingLosses_pn5n6_c20210615__20210616__srt--StatementGeographicalAxis__custom--NJMember__srt--RangeAxis__srt--MaximumMember_zM14sOMsind"&gt;1.4
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million under the current year program.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;




&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;In
June 2018, the Company entered into a Credit Agreement with Horizon Technology Finance Corporation (&#x201c;Horizon&#x201d;) that provided
$&lt;span id="xdx_902_eus-gaap--ProceedsFromContributedCapital_pn6n6_c20180601__20180630__us-gaap--TypeOfArrangementAxis__custom--HorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_zdLw2GbVEqGg"&gt;10
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million in capital (the &#x201c;Horizon Credit
Agreement&#x201d;). The obligations under the Horizon Credit Agreement are secured by a first-priority security interest in substantially
all assets of Celsion other than intellectual property assets. Payments under the loan agreement are interest only (calculated based
on one-month LIBOR plus &lt;span id="xdx_90D_eus-gaap--DebtInstrumentInterestRateStatedPercentage_iI_pid_dp_uPercentage_c20180630__us-gaap--TypeOfArrangementAxis__custom--HorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember__us-gaap--VariableRateAxis__us-gaap--LondonInterbankOfferedRateLIBORMember_zVwTUEla0Zqh"&gt;7.625&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;%)
for the first 24 months through July 2020, followed by a 21-month amortization period of principal and interest starting on August 1,
2020 and ending through the scheduled maturity date on April 1, 2023. On August 28, 2020, in connection with an Amendment to the Horizon
Credit Agreement, Celsion repaid $&lt;span id="xdx_90E_eus-gaap--RepaymentsOfNotesPayable_pn6n6_c20200827__20200828__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_zQaoltFZ080c"&gt;5
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million of the $&lt;span id="xdx_907_eus-gaap--DebtInstrumentFaceAmount_iI_pn6n6_c20200828__us-gaap--TypeOfArrangementAxis__custom--HorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_zJqDwhPMg24e"&gt;10
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million loan and $&lt;span id="xdx_902_ecustom--PaymentOfDebtEndTermCharges_pn5n6_c20200827__20200828__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_z5f0yRKT1L5k"&gt;0.2
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million in related end of term charges, and the
remaining $&lt;span id="xdx_90E_eus-gaap--DebtInstrumentFaceAmount_iI_pn6n6_c20200828__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_z0bp8AxcWkHd"&gt;5
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million in obligations were restructured. As
more fully discussed in Note 11 to these financial statements, in June 2021, the Company entered into a $&lt;span id="xdx_907_eus-gaap--LineOfCreditFacilityMaximumBorrowingCapacity_iI_pn6n6_c20210630__us-gaap--RelatedPartyTransactionsByRelatedPartyAxis__custom--SiliconValleyBankMember__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_zV2Rv9i8JACe"&gt;10
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million loan facility with Silicon Valley Bank.
The Company immediately used $&lt;span id="xdx_90D_ecustom--RepaymentOfOutstandingIndebtednessAmount_iI_pn6n6_c20210630__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_zNLFG1E2xTB3"&gt;6
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million from this facility to retire all outstanding
indebtedness with Horizon Technology Finance Corporation. The remaining $&lt;span id="xdx_90B_eus-gaap--LineOfCreditFacilityRemainingBorrowingCapacity_iI_pn6n6_c20210630__us-gaap--RelatedPartyTransactionsByRelatedPartyAxis__custom--SiliconValleyBankMember__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_zxSF6sRCR6Dg"&gt;4
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million will be available to be drawn down up
to 12 months after closing and will be used for working capital and to fund the advancement of the Company&#x2019;s product pipelines.
The funding is in the form of money market secured indebtedness bearing interest at a calculated WSJ Prime-based variable rate (currently
&lt;span id="xdx_907_eus-gaap--DebtInstrumentInterestRateStatedPercentage_iI_pid_dp_uPercentage_c20210630__us-gaap--RelatedPartyTransactionsByRelatedPartyAxis__custom--SiliconValleyBankMember__us-gaap--VariableRateAxis__us-gaap--PrimeRateMember__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_zwZJPMZvFLd4"&gt;3.25&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;%).
&lt;span id="xdx_90C_eus-gaap--DebtInstrumentDescription_c20210101__20210630__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_zf4PMOmqOnt5"&gt;Payments
under the loan agreement are interest only for the first 24 months after loan closing, followed by a 24-month amortization period of
principal and interest through the scheduled maturity date.&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;As
more fully discussed in Note 12, during 2021 through the date of the filing of this Quarterly Report on Form 10-Q, the Company has raised
approximately $&lt;span id="xdx_901_eus-gaap--ProceedsFromContributedCapital_pn5n6_c20210317__20210319__us-gaap--TypeOfArrangementAxis__custom--CapitalOnDemandTMSalesAgreementMember__dei--LegalEntityAxis__custom--JonesTradingInstitutionalServicesLLCMember_za4ISqmWMfL4"&gt;6.9
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million in gross proceeds from the use of its
JonesTrading Capital on Demand&lt;sup&gt;TM&lt;/sup&gt; financing facility, $&lt;span id="xdx_903_eus-gaap--DebtInstrumentFaceAmount_iI_pn6n6_c20210131__us-gaap--TypeOfArrangementAxis__custom--CapitalOnDemandTMSalesAgreementMember__dei--LegalEntityAxis__custom--JonesTradingInstitutionalServicesLLCMember_zqPg8iwXU2p2"&gt;35
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million from a registered direct financing completed
in January 2021, $&lt;span id="xdx_909_eus-gaap--DebtInstrumentFaceAmount_iI_pn6n6_c20210405__us-gaap--TypeOfArrangementAxis__custom--CapitalOnDemandTMSalesAgreementMember__dei--LegalEntityAxis__custom--JonesTradingInstitutionalServicesLLCMember_zQjCKudCqbe8"&gt;15
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million from a registered direct financing completed
on April 5, 2021, and $&lt;span id="xdx_907_eus-gaap--ProceedsFromWarrantExercises_pn5n6_c20210101__20210131__us-gaap--TypeOfArrangementAxis__custom--CapitalOnDemandTMSalesAgreementMember__dei--LegalEntityAxis__custom--JonesTradingInstitutionalServicesLLCMember_zK45SMEHZAQk"&gt;1.5
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million from warrant exercises. With $&lt;span id="xdx_906_ecustom--CashAndCashEquivalentsRestrictedCashShorttermInvestmentsAndReceivableOnSaleOfNetOperatingLosses_iI_pn5n6_c20210630__dei--LegalEntityAxis__custom--JonesTradingInstitutionalServicesLLCMember__us-gaap--TypeOfArrangementAxis__custom--CapitalOnDemandTMSalesAgreementMember_zAvkbZ7Ym9Yl"&gt;64.5
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million in cash and cash equivalents, restricted
cash, short-term investments and interest receivable, the Company believes it has sufficient capital resources to fund
its operations through the end of 2024.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
Company has based its estimates on assumptions that may prove to be wrong. The Company may need to obtain additional funds sooner or
in greater amounts than it currently anticipates. Potential sources of financing include strategic relationships, public or private sales
of the Company&#x2019;s shares or debt, the sale of the Company&#x2019;s State of New Jersey net operating losses and other sources. If
the Company raises funds by selling additional shares of common stock or other securities convertible into common stock, the ownership
interest of existing stockholders may be diluted.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

</us-gaap:SubstantialDoubtAboutGoingConcernTextBlock>
    <us-gaap:RetainedEarningsAccumulatedDeficit contextRef="AsOf2021-06-30" decimals="-6" unitRef="USD">-323000000</us-gaap:RetainedEarningsAccumulatedDeficit>
    <CLSN:CashAndCashEquivalentsRestrictedCashShorttermInvestmentsAndReceivableOnSaleOfNetOperatingLosses contextRef="AsOf2021-06-30" decimals="-5" unitRef="USD">64500000</CLSN:CashAndCashEquivalentsRestrictedCashShorttermInvestmentsAndReceivableOnSaleOfNetOperatingLosses>
    <CLSN:NetProceedsFromSaleOfNetOperatingLosses
      contextRef="From2018-01-012018-12-31_custom_NJMember"
      decimals="-6"
      unitRef="USD">13000000</CLSN:NetProceedsFromSaleOfNetOperatingLosses>
    <CLSN:NetProceedsFromSaleOfNetOperatingLosses
      contextRef="From2019-01-012019-12-31_custom_NJMember"
      decimals="-5"
      unitRef="USD">12200000</CLSN:NetProceedsFromSaleOfNetOperatingLosses>
    <CLSN:NetProceedsFromSaleOfNetOperatingLosses
      contextRef="From2020-09-012020-09-30_custom_NJMember"
      decimals="-5"
      unitRef="USD">2000000.0</CLSN:NetProceedsFromSaleOfNetOperatingLosses>
    <CLSN:ReceivableOnSaleOfNetOperatingLosses contextRef="AsOf2021-06-30" decimals="-4" unitRef="USD">1850000</CLSN:ReceivableOnSaleOfNetOperatingLosses>
    <CLSN:NetProceedsFromSaleOfNetOperatingLosses
      contextRef="From2021-05-092021-05-10_custom_NJMember_srt_MinimumMember"
      decimals="-6"
      unitRef="USD">15000000</CLSN:NetProceedsFromSaleOfNetOperatingLosses>
    <CLSN:NetProceedsFromSaleOfNetOperatingLosses
      contextRef="From2021-05-092021-05-10_custom_NJMember_srt_MaximumMember"
      decimals="-6"
      unitRef="USD">20000000</CLSN:NetProceedsFromSaleOfNetOperatingLosses>
    <CLSN:NetProceedsFromSaleOfNetOperatingLosses
      contextRef="From2021-06-152021-06-16_custom_NJMember"
      decimals="-5"
      unitRef="USD">1600000</CLSN:NetProceedsFromSaleOfNetOperatingLosses>
    <CLSN:NetProceedsFromSaleOfNetOperatingLosses
      contextRef="From2021-06-152021-06-16_custom_NJMember_srt_MaximumMember"
      decimals="-5"
      unitRef="USD">1400000</CLSN:NetProceedsFromSaleOfNetOperatingLosses>
    <us-gaap:ProceedsFromContributedCapital
      contextRef="From2018-06-012018-06-30_custom_HorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember"
      decimals="-6"
      unitRef="USD">10000000</us-gaap:ProceedsFromContributedCapital>
    <us-gaap:DebtInstrumentInterestRateStatedPercentage
      contextRef="AsOf2018-06-30_custom_HorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember_us-gaap_LondonInterbankOfferedRateLIBORMember"
      decimals="INF"
      unitRef="Percentage">0.07625</us-gaap:DebtInstrumentInterestRateStatedPercentage>
    <us-gaap:RepaymentsOfNotesPayable
      contextRef="From2020-08-272020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember"
      decimals="-6"
      unitRef="USD">5000000</us-gaap:RepaymentsOfNotesPayable>
    <us-gaap:DebtInstrumentFaceAmount
      contextRef="AsOf2020-08-28_custom_HorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember"
      decimals="-6"
      unitRef="USD">10000000</us-gaap:DebtInstrumentFaceAmount>
    <CLSN:PaymentOfDebtEndTermCharges
      contextRef="From2020-08-272020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember"
      decimals="-5"
      unitRef="USD">200000</CLSN:PaymentOfDebtEndTermCharges>
    <us-gaap:DebtInstrumentFaceAmount
      contextRef="AsOf2020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember"
      decimals="-6"
      unitRef="USD">5000000</us-gaap:DebtInstrumentFaceAmount>
    <us-gaap:LineOfCreditFacilityMaximumBorrowingCapacity
      contextRef="AsOf2021-06-30_custom_SiliconValleyBankMember_custom_SVBLoanFacilityMember"
      decimals="-6"
      unitRef="USD">10000000</us-gaap:LineOfCreditFacilityMaximumBorrowingCapacity>
    <CLSN:RepaymentOfOutstandingIndebtednessAmount
      contextRef="AsOf2021-06-30_custom_HorizonTechnologyFinanceCorporationMember_custom_SVBLoanFacilityMember"
      decimals="-6"
      unitRef="USD">6000000</CLSN:RepaymentOfOutstandingIndebtednessAmount>
    <us-gaap:LineOfCreditFacilityRemainingBorrowingCapacity
      contextRef="AsOf2021-06-30_custom_SiliconValleyBankMember_custom_SVBLoanFacilityMember"
      decimals="-6"
      unitRef="USD">4000000</us-gaap:LineOfCreditFacilityRemainingBorrowingCapacity>
    <us-gaap:DebtInstrumentInterestRateStatedPercentage
      contextRef="AsOf2021-06-30_custom_SiliconValleyBankMember_us-gaap_PrimeRateMember_custom_SVBLoanFacilityMember"
      decimals="INF"
      unitRef="Percentage">0.0325</us-gaap:DebtInstrumentInterestRateStatedPercentage>
    <us-gaap:DebtInstrumentDescription contextRef="From2021-01-012021-06-30_custom_SVBLoanFacilityMember">Payments
under the loan agreement are interest only for the first 24 months after loan closing, followed by a 24-month amortization period of
principal and interest through the scheduled maturity date.</us-gaap:DebtInstrumentDescription>
    <us-gaap:ProceedsFromContributedCapital
      contextRef="From2021-03-172021-03-19_custom_CapitalOnDemandTMSalesAgreementMember_custom_JonesTradingInstitutionalServicesLLCMember"
      decimals="-5"
      unitRef="USD">6900000</us-gaap:ProceedsFromContributedCapital>
    <us-gaap:DebtInstrumentFaceAmount
      contextRef="AsOf2021-01-31_custom_CapitalOnDemandTMSalesAgreementMember_custom_JonesTradingInstitutionalServicesLLCMember"
      decimals="-6"
      unitRef="USD">35000000</us-gaap:DebtInstrumentFaceAmount>
    <us-gaap:DebtInstrumentFaceAmount
      contextRef="AsOf2021-04-05_custom_CapitalOnDemandTMSalesAgreementMember_custom_JonesTradingInstitutionalServicesLLCMember"
      decimals="-6"
      unitRef="USD">15000000</us-gaap:DebtInstrumentFaceAmount>
    <us-gaap:ProceedsFromWarrantExercises
      contextRef="From2021-01-012021-01-31_custom_CapitalOnDemandTMSalesAgreementMember_custom_JonesTradingInstitutionalServicesLLCMember"
      decimals="-5"
      unitRef="USD">1500000</us-gaap:ProceedsFromWarrantExercises>
    <CLSN:CashAndCashEquivalentsRestrictedCashShorttermInvestmentsAndReceivableOnSaleOfNetOperatingLosses
      contextRef="AsOf2021-06-30_custom_JonesTradingInstitutionalServicesLLCMember_custom_CapitalOnDemandTMSalesAgreementMember"
      decimals="-5"
      unitRef="USD">64500000</CLSN:CashAndCashEquivalentsRestrictedCashShorttermInvestmentsAndReceivableOnSaleOfNetOperatingLosses>
    <us-gaap:NewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock contextRef="From2021-01-01to2021-06-30">&lt;p id="xdx_801_eus-gaap--NewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock_z9QsB29XOOTj" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
4. &lt;span id="xdx_82F_z5vVHZtyOqXc"&gt;New Accounting Pronouncements&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;From
time to time, new accounting pronouncements are issued by the Financial Accounting Standards Board (FASB) and are adopted by us as of
the specified effective date. Unless otherwise discussed, we believe that the impact of recently issued accounting pronouncements will
not have a material impact on the Company&#x2019;s condensed consolidated financial position, results of operations, and cash flows, or
do not apply to our operations.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;In
June 2016, the FASB issued ASU No. 2016-13, &#x201c;Financial Instruments &#x2013; Credit Losses (Topic 326): Measurement of Credit Losses
on Financial Instruments&#x201d;, which modifies the measurement of expected credit losses on certain financial instruments. The Company
adopted ASU 2016-13 in the first quarter of 2021 utilizing the modified retrospective transition method. Based on the composition of
the Company&#x2019;s investment portfolio and current market conditions, the adoption of ASU 2016-13 did not have a material impact on
its consolidated financial statements.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;In
December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740). The standard simplifies the accounting for incomes taxes by
removing certain exceptions to the general principles in Topic 740 related to the approach for intra-period tax allocation and the recognition
of deferred tax liabilities for outside basis differences. The standard also clarifies the accounting for transactions that result in
a step-up in the tax basis of goodwill. The standard also improves consistent application of and simplifies GAAP for other areas of Topic
740 by clarifying and amending existing guidance. The amendment is effective for fiscal years, and interim periods within those fiscal
years, beginning after December 15, 2020. The Company adopted this standard during the first quarter of 2021. The adoption of ASU 2019-12
did not have a material impact on its consolidated financial statements.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;In
connection with the upcoming elimination of the London Inter-bank Offered Rate, (&#x201c;LIBOR&#x201d;) and other reference interest rates,
the FASB issued ASU 2020-04, Reference Rate Reform (Topic 848) Facilitation of the Effects of Reference Reform on Financial Reporting.
ASU 2020-04, which is available for contract modifications and hedging relationship modifications entered into or evaluated before December
31, 2022, provides certain practical expedients related to simplifying the accounting for contract modifications resulting from the change
in terms from LIBOR to a new required interest rate benchmark. The Company is currently evaluating the effects of adopting this accounting
standards update.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

</us-gaap:NewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock>
    <us-gaap:RestrictedAssetsDisclosureTextBlock contextRef="From2021-01-01to2021-06-30">&lt;p id="xdx_80F_eus-gaap--RestrictedAssetsDisclosureTextBlock_zSgNtnKozLjb" style="font: 10pt Times New Roman, Times, Serif; margin: 0"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
5. &lt;span id="xdx_82D_z5d9qsvgwDE2"&gt;Restricted Cash&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;&#160;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;As
a condition of the $&lt;span id="xdx_901_eus-gaap--LineOfCreditFacilityMaximumBorrowingCapacity_iI_pn6n6_c20210618__us-gaap--RelatedPartyTransactionsByRelatedPartyAxis__custom--SiliconValleyBankMember__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_zI0eQmDX1ONi"&gt;10
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million loan facility with Silicon Valley Bank
(&#x201c;SVB&#x201d;) entered into on June 18, 2021 as further discussed in Note 11, &lt;span id="xdx_900_eus-gaap--LineOfCreditFacilityDescription_c20210601__20210618__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_zVcmOyGoWY94"&gt;the
Company is required at all times to maintain on deposit with SVB as cash collateral in a segregated money market bank account
in the name of the Company, unrestricted and unencumbered cash in an amount of at least 100% of the aggregate outstanding amount of the
SVB loan facility. SVB may restrict withdrawals or transfers by or on behalf of the Company that would violate this requirement.
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The required reserve totaled $&lt;span id="xdx_90A_eus-gaap--RestrictedInvestments_iI_pn5n6_c20210630__us-gaap--RelatedPartyTransactionsByRelatedPartyAxis__custom--SiliconValleyBankMember__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_ziQKADbcEov2"&gt;6.0
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million as of June 30, 2021. This amount is presented
in part as restricted cash in other non-current assets on the accompanying condensed consolidated balance sheets.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;




&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p id="xdx_898_eus-gaap--ScheduleOfRestrictedCashAndCashEquivalentsTextBlock_z8WfHHRzm9Ci" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
following table reconciles cash and cash equivalents and restricted cash per the balance sheet to the condensed statement of cash flows:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; display: none; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8B9_zu6BBBVVxRYh"&gt;Schedule
of Cash and Cash Equivalents and Restricted Cash&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_499_20210630_zGNQaOpaYT13" style="font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;June
    30,&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_493_20200630_zxHHC3hlb117" style="font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;June
    30,&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2021&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2020&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_405_eus-gaap--CashAndCashEquivalentsAtCarryingValue_iI_pp0p0_maCCERCz29N_ztdehdP1Lfm9" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 60%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Cash and cash equivalents&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;26,437,424&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;22,653,760&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_403_eus-gaap--RestrictedInvestments_iI_pp0p0_maCCERCz29N_zVPUqCGAxf5c" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Money market investments,
    restricted&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;6,000,000&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0773"&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;-&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_404_eus-gaap--CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_iTI_pp0p0_mtCCERCz29N_zHaEkfeLA1P2" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-left: 10pt; padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Total&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;32,437,424&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;22,653,760&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p id="xdx_8AA_zpb3DK2tazK9" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

</us-gaap:RestrictedAssetsDisclosureTextBlock>
    <us-gaap:LineOfCreditFacilityMaximumBorrowingCapacity
      contextRef="AsOf2021-06-18_custom_SiliconValleyBankMember_custom_SVBLoanFacilityMember"
      decimals="-6"
      unitRef="USD">10000000</us-gaap:LineOfCreditFacilityMaximumBorrowingCapacity>
    <us-gaap:LineOfCreditFacilityDescription contextRef="From2021-06-012021-06-18_custom_SVBLoanFacilityMember">the
Company is required at all times to maintain on deposit with SVB as cash collateral in a segregated money market bank account
in the name of the Company, unrestricted and unencumbered cash in an amount of at least 100% of the aggregate outstanding amount of the
SVB loan facility. SVB may restrict withdrawals or transfers by or on behalf of the Company that would violate this requirement.</us-gaap:LineOfCreditFacilityDescription>
    <us-gaap:RestrictedInvestments
      contextRef="AsOf2021-06-30_custom_SiliconValleyBankMember_custom_SVBLoanFacilityMember"
      decimals="-5"
      unitRef="USD">6000000.0</us-gaap:RestrictedInvestments>
    <us-gaap:ScheduleOfRestrictedCashAndCashEquivalentsTextBlock contextRef="From2021-01-01to2021-06-30">&lt;p id="xdx_898_eus-gaap--ScheduleOfRestrictedCashAndCashEquivalentsTextBlock_z8WfHHRzm9Ci" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
following table reconciles cash and cash equivalents and restricted cash per the balance sheet to the condensed statement of cash flows:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; display: none; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8B9_zu6BBBVVxRYh"&gt;Schedule
of Cash and Cash Equivalents and Restricted Cash&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_499_20210630_zGNQaOpaYT13" style="font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;June
    30,&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_493_20200630_zxHHC3hlb117" style="font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;June
    30,&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2021&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2020&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_405_eus-gaap--CashAndCashEquivalentsAtCarryingValue_iI_pp0p0_maCCERCz29N_ztdehdP1Lfm9" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 60%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Cash and cash equivalents&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;26,437,424&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;22,653,760&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_403_eus-gaap--RestrictedInvestments_iI_pp0p0_maCCERCz29N_zVPUqCGAxf5c" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Money market investments,
    restricted&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;6,000,000&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0773"&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;-&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_404_eus-gaap--CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_iTI_pp0p0_mtCCERCz29N_zHaEkfeLA1P2" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-left: 10pt; padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Total&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;32,437,424&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;22,653,760&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

</us-gaap:ScheduleOfRestrictedCashAndCashEquivalentsTextBlock>
    <us-gaap:CashAndCashEquivalentsAtCarryingValue contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">26437424</us-gaap:CashAndCashEquivalentsAtCarryingValue>
    <us-gaap:CashAndCashEquivalentsAtCarryingValue contextRef="AsOf2020-06-30" decimals="0" unitRef="USD">22653760</us-gaap:CashAndCashEquivalentsAtCarryingValue>
    <us-gaap:RestrictedInvestments contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">6000000</us-gaap:RestrictedInvestments>
    <us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">32437424</us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents>
    <us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents contextRef="AsOf2020-06-30" decimals="0" unitRef="USD">22653760</us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents>
    <us-gaap:EarningsPerShareTextBlock contextRef="From2021-01-01to2021-06-30">&lt;p id="xdx_80A_eus-gaap--EarningsPerShareTextBlock_zwTEQ6ataZc8" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
6. &lt;span id="xdx_822_za03PqMUoPEf"&gt;Net Loss per Common Share&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Basic
loss per share is calculated based upon the net loss available to common shareholders divided by the weighted average number of common
shares outstanding during the period. Diluted loss per share is calculated after adjusting the denominator of the basic earnings per
share computation for the effects of all dilutive potential common shares outstanding during the period. The dilutive effects of preferred
stock, options and warrants and their equivalents are computed using the treasury stock method.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
total number of shares of common stock issuable upon exercise of warrants, stock option grants and equity awards were &lt;span id="xdx_907_ecustom--NumberOfSharesOfCommonStockIssuableUponExerciseOfWarrantsAndEquityAwards_pid_c20210101__20210630_zmsnKy2rNZg4"&gt;9,325,228
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;and &lt;span id="xdx_901_ecustom--NumberOfSharesOfCommonStockIssuableUponExerciseOfWarrantsAndEquityAwards_pid_c20200101__20200630_z48gjb7JWcOk"&gt;8,560,124
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;shares for the three and six-month periods ended
June 30, 2021 and 2020, respectively. Warrants with an exercise price of $&lt;span id="xdx_907_eus-gaap--ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_c20210630_pdd"&gt;0.01
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;exercisable for &lt;span id="xdx_90F_ecustom--NumberOfSharesOfCommonStockIssuedInCalculationBasicLossPerShare_pid_c20200101__20200630_za86XsP5oyP7"&gt;200,000
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;shares of common stock were considered issued
in calculating basic loss per share during the first six-months of 2020. These warrants were exercised in October 2020. For the three
and six-month periods ended June 30, 2021 and 2020, diluted loss per common share was the same as basic loss per common share as the
other warrants and equity awards that were convertible into shares of the Company&#x2019;s common stock were excluded from the calculation
of diluted loss per common share as their effect would have been anti-dilutive. The Company did not pay any dividends during the first
six months of 2021 or 2020.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

</us-gaap:EarningsPerShareTextBlock>
    <CLSN:NumberOfSharesOfCommonStockIssuableUponExerciseOfWarrantsAndEquityAwards
      contextRef="From2021-01-01to2021-06-30"
      decimals="INF"
      unitRef="Shares">9325228</CLSN:NumberOfSharesOfCommonStockIssuableUponExerciseOfWarrantsAndEquityAwards>
    <CLSN:NumberOfSharesOfCommonStockIssuableUponExerciseOfWarrantsAndEquityAwards
      contextRef="From2020-01-012020-06-30"
      decimals="INF"
      unitRef="Shares">8560124</CLSN:NumberOfSharesOfCommonStockIssuableUponExerciseOfWarrantsAndEquityAwards>
    <us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1
      contextRef="AsOf2021-06-30"
      decimals="INF"
      unitRef="USDPShares">0.01</us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1>
    <CLSN:NumberOfSharesOfCommonStockIssuedInCalculationBasicLossPerShare
      contextRef="From2020-01-012020-06-30"
      decimals="INF"
      unitRef="Shares">200000</CLSN:NumberOfSharesOfCommonStockIssuedInCalculationBasicLossPerShare>
    <us-gaap:InvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock contextRef="From2021-01-01to2021-06-30">&lt;p id="xdx_80A_eus-gaap--InvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock_zlpYMOEScUfh" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
7. &lt;span id="xdx_828_zpgEeELWxkTd"&gt;Investment in Debt Securities Available for Sale&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Investments
in debt securities available for sale with a fair value of $&lt;span id="xdx_901_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20210630_pp0p0"&gt;31,923,285
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;as of June 30, 2021, consisted of government
backed debt securities and commercial paper. These investments are valued at estimated fair value, with unrealized gains and losses reported
as a separate component of stockholders&#x2019; equity in accumulated other comprehensive loss. The Company only had investments in cash
and cash equivalents on December 31, 2020.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Investments
in debt securities available for sale are evaluated periodically to determine whether a decline in their value is other than temporary.
The term &#x201c;other than temporary&#x201d; is not intended to indicate a permanent decline in value. Rather, it means that the prospects
for near term recovery of value are not necessarily favorable, or that there is a lack of evidence to support fair values equal to, or
greater than, the carrying value of the security. Management reviews criteria such as the magnitude and duration of the decline, as well
as the reasons for the decline, to predict whether the loss in value is other than temporary. Once a decline in value is determined to
be other than temporary, the value of the security is reduced and a corresponding charge to earnings is recognized.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p id="xdx_89A_eus-gaap--AvailableForSaleSecuritiesTextBlock_zRaide2ifxYk" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;A
summary of the cost, fair value and maturities of the Company&#x2019;s short-term investments is as follows:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; display: none; margin: 0"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8BC_z87fG4UsVTe9"&gt;Schedule
of Cost, Fair Value and Maturities of Short Term Investments&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;June
    30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;December
    31, 2020&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Cost&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Fair
    Value&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Cost&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Fair
    Value&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="font-weight: bold; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Short-term investments&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="width: 40%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Commercial paper&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98A_eus-gaap--ShortTermInvestments_c20210630__us-gaap--FinancialInstrumentAxis__us-gaap--CommercialPaperMember_pp0p0" style="width: 11%; text-align: right" title="Short-term investments - Cost"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;7,795,035&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98E_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20210630__us-gaap--FinancialInstrumentAxis__us-gaap--CommercialPaperMember_pp0p0" style="width: 11%; text-align: right" title="Short-term investments - Fair Value"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;7,792,785&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_980_eus-gaap--ShortTermInvestments_c20201231__us-gaap--FinancialInstrumentAxis__us-gaap--CommercialPaperMember_pp0p0" style="width: 11%; text-align: right" title="Short-term investments - Cost"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0793"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98D_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20201231__us-gaap--FinancialInstrumentAxis__us-gaap--CommercialPaperMember_pp0p0" style="width: 11%; text-align: right" title="Short-term investments - Fair Value"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0795"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Government backed debt
    securities&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_985_eus-gaap--ShortTermInvestments_c20210630__us-gaap--FinancialInstrumentAxis__custom--GovernmentBackedDebtSecuritiesMember_pp0p0" style="border-bottom: Black 1.5pt solid; text-align: right" title="Short-term investments - Cost"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;24,132,020&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98A_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20210630__us-gaap--FinancialInstrumentAxis__custom--GovernmentBackedDebtSecuritiesMember_pp0p0" style="border-bottom: Black 1.5pt solid; text-align: right" title="Short-term investments - Fair Value"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;24,130,500&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;-&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;-&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="font-weight: bold; padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Total&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_986_eus-gaap--ShortTermInvestments_c20210630_pp0p0" style="border-bottom: Black 2.5pt double; text-align: right" title="Short-term investments - Cost"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;31,927,055&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_989_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20210630_pp0p0" style="border-bottom: Black 2.5pt double; text-align: right" title="Short-term investments - Fair Value"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;31,923,285&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_981_eus-gaap--ShortTermInvestments_c20201231_pp0p0" style="border-bottom: Black 2.5pt double; text-align: right" title="Short-term investments - Cost"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0805"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98C_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20201231_pp0p0" style="border-bottom: Black 2.5pt double; text-align: right" title="Short-term investments - Fair Value"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0807"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;June
    30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;December
    31, 2020&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Cost&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Fair
    Value&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Cost&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Fair
    Value&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="font-weight: bold; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Short-term investment maturities&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font-weight: bold; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font-weight: bold; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font-weight: bold; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font-weight: bold; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="width: 40%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Within 3 months&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_985_ecustom--DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingWithinThreeMonthsAmortizedCost_c20210630_pp0p0" style="width: 11%; text-align: right" title="Short-term investment maturities - Within 3 months, cost"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2,999,420&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_989_ecustom--DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingWithinThreeMonthsFairValue_c20210630_pp0p0" style="width: 11%; text-align: right" title="Short-term investment maturities - Within 3 months, fair value"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;7,792,785&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_986_ecustom--DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingWithinThreeMonthsAmortizedCost_c20201231_pp0p0" style="width: 11%; text-align: right" title="Short-term investment maturities - Within 3 months, cost"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0813"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_984_ecustom--DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingWithinThreeMonthsFairValue_c20201231_pp0p0" style="width: 11%; text-align: right" title="Short-term investment maturities - Within 3 months, fair value"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0815"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Between 3-12 months&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_981_ecustom--DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingBetweenThreeAndTwelveMonthsAmortizedCost_c20210630_pp0p0" style="border-bottom: Black 1.5pt solid; text-align: right" title="Short-term investment maturities - Between 3-12 months, cost"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;28,927,635&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98E_ecustom--DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingBetweenThreeAndTwelveMonthsFairValue_c20210630_pp0p0" style="border-bottom: Black 1.5pt solid; text-align: right" title="Short-term investment maturities - Between 3-12 months, fair value"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;24,130,500&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_984_ecustom--DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingBetweenThreeAndTwelveMonthsAmortizedCost_c20201231_pp0p0" style="border-bottom: Black 1.5pt solid; text-align: right" title="Short-term investment maturities - Between 3-12 months, cost"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0821"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98D_ecustom--DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingBetweenThreeAndTwelveMonthsFairValue_c20201231_pp0p0" style="border-bottom: Black 1.5pt solid; text-align: right" title="Short-term investment maturities - Between 3-12 months, fair value"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0823"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="font-weight: bold; padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Total&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98B_ecustom--AvailableForSaleDebtSecuritiesAmortizedCostBasisCurrent_c20210630_pp0p0" style="border-bottom: Black 2.5pt double; text-align: right" title="Total, cost"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;31,927,055&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_983_eus-gaap--AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate_c20210630_pp0p0" style="border-bottom: Black 2.5pt double; text-align: right" title="Total, fair value"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;31,923,285&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_988_ecustom--AvailableForSaleDebtSecuritiesAmortizedCostBasisCurrent_c20201231_pp0p0" style="border-bottom: Black 2.5pt double; text-align: right" title="Total, cost"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0829"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_980_eus-gaap--AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate_c20201231_pp0p0" style="border-bottom: Black 2.5pt double; text-align: right" title="Total, fair value"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0831"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p id="xdx_8AE_zM8e9HIJINVg" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;




&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p id="xdx_899_eus-gaap--ScheduleOfUnrealizedLossOnInvestmentsTableTextBlock_zoRkyQc8eJSh" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
following table shows the Company&#x2019;s investment in debt securities available for sale gross unrealized gains (losses) and fair value
by investment category and length of time that individual securities have been in a continuous unrealized loss position at June 30, 2021
and December 31, 2020. The Company has reviewed individual securities to determine whether a decline in fair value below the amortizable
cost basis is other than temporary.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; display: none; margin: 0; text-align: justify"&gt;&lt;span id="xdx_8BD_zpnMxAxahwPg" style="font: 10pt Times New Roman, Times, Serif"&gt;Summary
of Investment Securities Gross Unrealized Gains (Losses)&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;June
    30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;December
    31, 2020&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Available
    for sale securities (all unrealized holding gains and losses are less than 12 months at date of measurement)&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Fair
    Value&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Unrealized
                                            Holding&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Gains
                                            (Losses)&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Fair
    Value&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Unrealized
                                            Holding&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Gains
                                            (Losses)&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 44%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Investments with unrealized gains&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_987_ecustom--AvailableForSaleSecuritiesUnrealizedGainsFairValue_iI_c20210630_z3kP7aYVfYY7" style="width: 11%; text-align: right" title="Investments with unrealized gains, Fair Value"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;5,998,980&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_989_ecustom--AvailableForSaleSecuritiesUnrealizedHoldingGainsLessThanTwelveMonths_iI_c20210630_z73yY5dYjkJj" style="width: 11%; text-align: right" title="Investments with unrealized gains, Unrealized Holding Gains (Losses)"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;1,073&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98E_ecustom--AvailableForSaleSecuritiesUnrealizedGainsFairValue_iI_c20201231_zEUHF5fxggM9" style="width: 9%; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0838"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98D_ecustom--AvailableForSaleSecuritiesUnrealizedHoldingGainsLessThanTwelveMonths_iI_c20201231_zJALWk90Uhec" style="width: 9%; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0839"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Investments with unrealized
    losses&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98C_ecustom--AvailableForSaleSecuritiesUnrealizedLossFairValue_iI_c20210630_z9UDyW8OCJEh" style="border-bottom: Black 1.5pt solid; text-align: right" title="Investments with unrealized losses, Fair Value"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;25,924,305&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_989_ecustom--AvailableForSaleSecuritiesUnrealizedHoldingLossesLessThanTwelveMonths_iI_c20210630_zlbRJMBli5Vc" style="border-bottom: Black 1.5pt solid; text-align: right" title="Investments with unrealized Losses, Unrealized Holding Gains (Losses)"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;(4,843&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;)&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_980_ecustom--AvailableForSaleSecuritiesUnrealizedLossFairValue_iI_c20201231_zEaBVYTqEBR" style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0844"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98B_ecustom--AvailableForSaleSecuritiesUnrealizedHoldingLossesLessThanTwelveMonths_iI_c20201231_zC9q5gqMTzC2" style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0845"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-left: 10pt; font-weight: bold; padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Total&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_989_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_c20210630_zd1pGBsy9UX3" style="border-bottom: Black 2.5pt double; text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;31,923,285&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_988_ecustom--AvailableForSaleSecuritiesUnrealizedHoldingGainsLossesLessThanTwelveMonths_iI_c20210630_zklx76pw00Xl" style="border-bottom: Black 2.5pt double; text-align: right" title="Investments with unrealized Gains (Losses), Unrealized Holding Gains (Losses)"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;(3,770&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;)&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98E_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20201231_zitrNAaI3459" style="border-bottom: Black 2.5pt double; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0850"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98A_ecustom--AvailableForSaleSecuritiesUnrealizedHoldingGainsLossesLessThanTwelveMonths_iI_c20201231_zMBfZ8IjgWek" style="border-bottom: Black 2.5pt double; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0851"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p id="xdx_8A4_zQnLlUZMRva7" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p id="xdx_89F_eus-gaap--InvestmentIncomeTextBlock_zFQTOKwfKVCf" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Investment
(loss) income, which includes net realized losses on sales of available for sale securities and investment income interest and
dividends, is summarized as follows:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; display: none; margin: 0"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8B2_zeRwJVgb5CRk"&gt;Summary
of Net Realized Losses on Sales of Available for Sale Securities and Investment Income Interest and Dividends&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="display: none; vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_494_20210401__20210630_zSHyDhyzLjZ6" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2021&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_493_20200401__20200630_zgTSeZK7Cr9e" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2020&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Three
                                            Months Ended&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;June
                                            30,&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2021&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2020&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_403_eus-gaap--InvestmentIncomeInterestAndDividend_maIINzj8E_zfdE28HysZqg" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 60%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Interest and dividends accrued
    and paid&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;1,436&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;18,095&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_409_eus-gaap--AvailableForSaleSecuritiesGrossRealizedGainLossNet_maIINzj8E_zSqSuTUlXRhc" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Realized (losses) gains&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;(1,785&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;)&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2,865&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_403_ecustom--InvestmentIncomeLossNonoperating_iT_pp0p0_mtIINzj8E_zhAI9SQfD4u6" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Investment (loss) income,
    net&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;(349&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;)&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;20,960&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="display: none; vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_495_20210101__20210630_zueeupzM32bg" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2021&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_494_20200101__20200630_zlvHlUejVj51" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2020&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Six
                                            Months Ended&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;June
                                            30,&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2021&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2020&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_400_eus-gaap--InvestmentIncomeInterestAndDividend_maIINz3xg_z2bCtAatVzL4" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 60%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Interest and dividends accrued
    and paid&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;3,847&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;63,172&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40C_eus-gaap--AvailableForSaleSecuritiesGrossRealizedGainLossNet_maIINz3xg_zLf2CPwQ83kc" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Realized (losses) gains&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;(1,785&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;)&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;46,097&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_402_ecustom--InvestmentIncomeLossNonoperating_iT_mtIINz3xg_zXBNfvUuLAe7" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Investment income, net&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2,062&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;109,269&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40F_ecustom--InvestmentIncomeLossNonoperating_iT_mtIINz3xg_zEY8MspCTele" style="display: none; vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Investment (loss) income,
    net&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2,062&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;109,269&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

</us-gaap:InvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock>
    <us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">31923285</us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent>
    <us-gaap:AvailableForSaleSecuritiesTextBlock contextRef="From2021-01-01to2021-06-30">&lt;p id="xdx_89A_eus-gaap--AvailableForSaleSecuritiesTextBlock_zRaide2ifxYk" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;A
summary of the cost, fair value and maturities of the Company&#x2019;s short-term investments is as follows:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; display: none; margin: 0"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8BC_z87fG4UsVTe9"&gt;Schedule
of Cost, Fair Value and Maturities of Short Term Investments&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;June
    30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;December
    31, 2020&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Cost&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Fair
    Value&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Cost&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Fair
    Value&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="font-weight: bold; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Short-term investments&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="width: 40%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Commercial paper&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98A_eus-gaap--ShortTermInvestments_c20210630__us-gaap--FinancialInstrumentAxis__us-gaap--CommercialPaperMember_pp0p0" style="width: 11%; text-align: right" title="Short-term investments - Cost"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;7,795,035&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98E_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20210630__us-gaap--FinancialInstrumentAxis__us-gaap--CommercialPaperMember_pp0p0" style="width: 11%; text-align: right" title="Short-term investments - Fair Value"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;7,792,785&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_980_eus-gaap--ShortTermInvestments_c20201231__us-gaap--FinancialInstrumentAxis__us-gaap--CommercialPaperMember_pp0p0" style="width: 11%; text-align: right" title="Short-term investments - Cost"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0793"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98D_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20201231__us-gaap--FinancialInstrumentAxis__us-gaap--CommercialPaperMember_pp0p0" style="width: 11%; text-align: right" title="Short-term investments - Fair Value"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0795"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Government backed debt
    securities&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_985_eus-gaap--ShortTermInvestments_c20210630__us-gaap--FinancialInstrumentAxis__custom--GovernmentBackedDebtSecuritiesMember_pp0p0" style="border-bottom: Black 1.5pt solid; text-align: right" title="Short-term investments - Cost"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;24,132,020&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98A_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20210630__us-gaap--FinancialInstrumentAxis__custom--GovernmentBackedDebtSecuritiesMember_pp0p0" style="border-bottom: Black 1.5pt solid; text-align: right" title="Short-term investments - Fair Value"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;24,130,500&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;-&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;-&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="font-weight: bold; padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Total&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_986_eus-gaap--ShortTermInvestments_c20210630_pp0p0" style="border-bottom: Black 2.5pt double; text-align: right" title="Short-term investments - Cost"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;31,927,055&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_989_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20210630_pp0p0" style="border-bottom: Black 2.5pt double; text-align: right" title="Short-term investments - Fair Value"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;31,923,285&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_981_eus-gaap--ShortTermInvestments_c20201231_pp0p0" style="border-bottom: Black 2.5pt double; text-align: right" title="Short-term investments - Cost"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0805"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98C_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20201231_pp0p0" style="border-bottom: Black 2.5pt double; text-align: right" title="Short-term investments - Fair Value"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0807"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;June
    30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;December
    31, 2020&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Cost&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Fair
    Value&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Cost&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Fair
    Value&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="font-weight: bold; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Short-term investment maturities&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font-weight: bold; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font-weight: bold; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font-weight: bold; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font-weight: bold; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="width: 40%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Within 3 months&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_985_ecustom--DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingWithinThreeMonthsAmortizedCost_c20210630_pp0p0" style="width: 11%; text-align: right" title="Short-term investment maturities - Within 3 months, cost"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2,999,420&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_989_ecustom--DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingWithinThreeMonthsFairValue_c20210630_pp0p0" style="width: 11%; text-align: right" title="Short-term investment maturities - Within 3 months, fair value"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;7,792,785&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_986_ecustom--DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingWithinThreeMonthsAmortizedCost_c20201231_pp0p0" style="width: 11%; text-align: right" title="Short-term investment maturities - Within 3 months, cost"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0813"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_984_ecustom--DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingWithinThreeMonthsFairValue_c20201231_pp0p0" style="width: 11%; text-align: right" title="Short-term investment maturities - Within 3 months, fair value"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0815"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Between 3-12 months&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_981_ecustom--DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingBetweenThreeAndTwelveMonthsAmortizedCost_c20210630_pp0p0" style="border-bottom: Black 1.5pt solid; text-align: right" title="Short-term investment maturities - Between 3-12 months, cost"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;28,927,635&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98E_ecustom--DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingBetweenThreeAndTwelveMonthsFairValue_c20210630_pp0p0" style="border-bottom: Black 1.5pt solid; text-align: right" title="Short-term investment maturities - Between 3-12 months, fair value"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;24,130,500&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_984_ecustom--DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingBetweenThreeAndTwelveMonthsAmortizedCost_c20201231_pp0p0" style="border-bottom: Black 1.5pt solid; text-align: right" title="Short-term investment maturities - Between 3-12 months, cost"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0821"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98D_ecustom--DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingBetweenThreeAndTwelveMonthsFairValue_c20201231_pp0p0" style="border-bottom: Black 1.5pt solid; text-align: right" title="Short-term investment maturities - Between 3-12 months, fair value"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0823"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="font-weight: bold; padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Total&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98B_ecustom--AvailableForSaleDebtSecuritiesAmortizedCostBasisCurrent_c20210630_pp0p0" style="border-bottom: Black 2.5pt double; text-align: right" title="Total, cost"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;31,927,055&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_983_eus-gaap--AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate_c20210630_pp0p0" style="border-bottom: Black 2.5pt double; text-align: right" title="Total, fair value"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;31,923,285&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_988_ecustom--AvailableForSaleDebtSecuritiesAmortizedCostBasisCurrent_c20201231_pp0p0" style="border-bottom: Black 2.5pt double; text-align: right" title="Total, cost"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0829"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_980_eus-gaap--AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate_c20201231_pp0p0" style="border-bottom: Black 2.5pt double; text-align: right" title="Total, fair value"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0831"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

</us-gaap:AvailableForSaleSecuritiesTextBlock>
    <us-gaap:ShortTermInvestments
      contextRef="AsOf2021-06-30_us-gaap_CommercialPaperMember"
      decimals="0"
      unitRef="USD">7795035</us-gaap:ShortTermInvestments>
    <us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent
      contextRef="AsOf2021-06-30_us-gaap_CommercialPaperMember"
      decimals="0"
      unitRef="USD">7792785</us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent>
    <us-gaap:ShortTermInvestments
      contextRef="AsOf2021-06-30_custom_GovernmentBackedDebtSecuritiesMember"
      decimals="0"
      unitRef="USD">24132020</us-gaap:ShortTermInvestments>
    <us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent
      contextRef="AsOf2021-06-30_custom_GovernmentBackedDebtSecuritiesMember"
      decimals="0"
      unitRef="USD">24130500</us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent>
    <us-gaap:ShortTermInvestments contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">31927055</us-gaap:ShortTermInvestments>
    <us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">31923285</us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent>
    <CLSN:DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingWithinThreeMonthsAmortizedCost contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">2999420</CLSN:DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingWithinThreeMonthsAmortizedCost>
    <CLSN:DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingWithinThreeMonthsFairValue contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">7792785</CLSN:DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingWithinThreeMonthsFairValue>
    <CLSN:DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingBetweenThreeAndTwelveMonthsAmortizedCost contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">28927635</CLSN:DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingBetweenThreeAndTwelveMonthsAmortizedCost>
    <CLSN:DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingBetweenThreeAndTwelveMonthsFairValue contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">24130500</CLSN:DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingBetweenThreeAndTwelveMonthsFairValue>
    <CLSN:AvailableForSaleDebtSecuritiesAmortizedCostBasisCurrent contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">31927055</CLSN:AvailableForSaleDebtSecuritiesAmortizedCostBasisCurrent>
    <us-gaap:AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">31923285</us-gaap:AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate>
    <us-gaap:ScheduleOfUnrealizedLossOnInvestmentsTableTextBlock contextRef="From2021-01-01to2021-06-30">&lt;p id="xdx_899_eus-gaap--ScheduleOfUnrealizedLossOnInvestmentsTableTextBlock_zoRkyQc8eJSh" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
following table shows the Company&#x2019;s investment in debt securities available for sale gross unrealized gains (losses) and fair value
by investment category and length of time that individual securities have been in a continuous unrealized loss position at June 30, 2021
and December 31, 2020. The Company has reviewed individual securities to determine whether a decline in fair value below the amortizable
cost basis is other than temporary.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; display: none; margin: 0; text-align: justify"&gt;&lt;span id="xdx_8BD_zpnMxAxahwPg" style="font: 10pt Times New Roman, Times, Serif"&gt;Summary
of Investment Securities Gross Unrealized Gains (Losses)&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;June
    30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;December
    31, 2020&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Available
    for sale securities (all unrealized holding gains and losses are less than 12 months at date of measurement)&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Fair
    Value&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Unrealized
                                            Holding&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Gains
                                            (Losses)&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Fair
    Value&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Unrealized
                                            Holding&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Gains
                                            (Losses)&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 44%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Investments with unrealized gains&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_987_ecustom--AvailableForSaleSecuritiesUnrealizedGainsFairValue_iI_c20210630_z3kP7aYVfYY7" style="width: 11%; text-align: right" title="Investments with unrealized gains, Fair Value"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;5,998,980&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_989_ecustom--AvailableForSaleSecuritiesUnrealizedHoldingGainsLessThanTwelveMonths_iI_c20210630_z73yY5dYjkJj" style="width: 11%; text-align: right" title="Investments with unrealized gains, Unrealized Holding Gains (Losses)"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;1,073&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98E_ecustom--AvailableForSaleSecuritiesUnrealizedGainsFairValue_iI_c20201231_zEUHF5fxggM9" style="width: 9%; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0838"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98D_ecustom--AvailableForSaleSecuritiesUnrealizedHoldingGainsLessThanTwelveMonths_iI_c20201231_zJALWk90Uhec" style="width: 9%; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0839"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Investments with unrealized
    losses&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98C_ecustom--AvailableForSaleSecuritiesUnrealizedLossFairValue_iI_c20210630_z9UDyW8OCJEh" style="border-bottom: Black 1.5pt solid; text-align: right" title="Investments with unrealized losses, Fair Value"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;25,924,305&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_989_ecustom--AvailableForSaleSecuritiesUnrealizedHoldingLossesLessThanTwelveMonths_iI_c20210630_zlbRJMBli5Vc" style="border-bottom: Black 1.5pt solid; text-align: right" title="Investments with unrealized Losses, Unrealized Holding Gains (Losses)"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;(4,843&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;)&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_980_ecustom--AvailableForSaleSecuritiesUnrealizedLossFairValue_iI_c20201231_zEaBVYTqEBR" style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0844"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98B_ecustom--AvailableForSaleSecuritiesUnrealizedHoldingLossesLessThanTwelveMonths_iI_c20201231_zC9q5gqMTzC2" style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0845"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-left: 10pt; font-weight: bold; padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Total&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_989_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_c20210630_zd1pGBsy9UX3" style="border-bottom: Black 2.5pt double; text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;31,923,285&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_988_ecustom--AvailableForSaleSecuritiesUnrealizedHoldingGainsLossesLessThanTwelveMonths_iI_c20210630_zklx76pw00Xl" style="border-bottom: Black 2.5pt double; text-align: right" title="Investments with unrealized Gains (Losses), Unrealized Holding Gains (Losses)"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;(3,770&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;)&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98E_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_iI_pp0p0_c20201231_zitrNAaI3459" style="border-bottom: Black 2.5pt double; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0850"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98A_ecustom--AvailableForSaleSecuritiesUnrealizedHoldingGainsLossesLessThanTwelveMonths_iI_c20201231_zMBfZ8IjgWek" style="border-bottom: Black 2.5pt double; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0851"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

</us-gaap:ScheduleOfUnrealizedLossOnInvestmentsTableTextBlock>
    <CLSN:AvailableForSaleSecuritiesUnrealizedGainsFairValue contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">5998980</CLSN:AvailableForSaleSecuritiesUnrealizedGainsFairValue>
    <CLSN:AvailableForSaleSecuritiesUnrealizedHoldingGainsLessThanTwelveMonths contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">1073</CLSN:AvailableForSaleSecuritiesUnrealizedHoldingGainsLessThanTwelveMonths>
    <CLSN:AvailableForSaleSecuritiesUnrealizedLossFairValue contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">25924305</CLSN:AvailableForSaleSecuritiesUnrealizedLossFairValue>
    <CLSN:AvailableForSaleSecuritiesUnrealizedHoldingLossesLessThanTwelveMonths contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">-4843</CLSN:AvailableForSaleSecuritiesUnrealizedHoldingLossesLessThanTwelveMonths>
    <us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">31923285</us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent>
    <CLSN:AvailableForSaleSecuritiesUnrealizedHoldingGainsLossesLessThanTwelveMonths contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">-3770</CLSN:AvailableForSaleSecuritiesUnrealizedHoldingGainsLossesLessThanTwelveMonths>
    <us-gaap:InvestmentIncomeTextBlock contextRef="From2021-01-01to2021-06-30">&lt;p id="xdx_89F_eus-gaap--InvestmentIncomeTextBlock_zFQTOKwfKVCf" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Investment
(loss) income, which includes net realized losses on sales of available for sale securities and investment income interest and
dividends, is summarized as follows:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; display: none; margin: 0"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8B2_zeRwJVgb5CRk"&gt;Summary
of Net Realized Losses on Sales of Available for Sale Securities and Investment Income Interest and Dividends&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="display: none; vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_494_20210401__20210630_zSHyDhyzLjZ6" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2021&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_493_20200401__20200630_zgTSeZK7Cr9e" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2020&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Three
                                            Months Ended&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;June
                                            30,&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2021&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2020&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_403_eus-gaap--InvestmentIncomeInterestAndDividend_maIINzj8E_zfdE28HysZqg" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 60%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Interest and dividends accrued
    and paid&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;1,436&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;18,095&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_409_eus-gaap--AvailableForSaleSecuritiesGrossRealizedGainLossNet_maIINzj8E_zSqSuTUlXRhc" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Realized (losses) gains&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;(1,785&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;)&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2,865&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_403_ecustom--InvestmentIncomeLossNonoperating_iT_pp0p0_mtIINzj8E_zhAI9SQfD4u6" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Investment (loss) income,
    net&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;(349&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;)&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;20,960&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="display: none; vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_495_20210101__20210630_zueeupzM32bg" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2021&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_494_20200101__20200630_zlvHlUejVj51" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2020&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Six
                                            Months Ended&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;June
                                            30,&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2021&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2020&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_400_eus-gaap--InvestmentIncomeInterestAndDividend_maIINz3xg_z2bCtAatVzL4" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 60%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Interest and dividends accrued
    and paid&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;3,847&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;63,172&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40C_eus-gaap--AvailableForSaleSecuritiesGrossRealizedGainLossNet_maIINz3xg_zLf2CPwQ83kc" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Realized (losses) gains&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;(1,785&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;)&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;46,097&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_402_ecustom--InvestmentIncomeLossNonoperating_iT_mtIINz3xg_zXBNfvUuLAe7" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Investment income, net&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2,062&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;109,269&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40F_ecustom--InvestmentIncomeLossNonoperating_iT_mtIINz3xg_zEY8MspCTele" style="display: none; vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Investment (loss) income,
    net&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2,062&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;109,269&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

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    <us-gaap:DerivativesAndFairValueTextBlock contextRef="From2021-01-01to2021-06-30">&lt;p id="xdx_804_eus-gaap--DerivativesAndFairValueTextBlock_zZIO6JLbLlU" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
8. &lt;span id="xdx_824_zNUNouQNdgKg"&gt;Fair Value Measurements&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;FASB
ASC Section 820, &lt;i&gt;Fair Value Measurements and Disclosures&lt;/i&gt; establishes a three-level hierarchy for fair value measurements which
requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. The
three levels of inputs that may be used to measure fair value are as follows:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0 0 0 0.5in; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Level
1: Quoted prices (unadjusted) or identical assets or liabilities in active markets that the entity has the ability to access as of the
measurement date;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0 0 0 0.5in; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0 0 0 0.5in; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Level
2: Significant other observable inputs other than Level 1 prices such as quoted prices for similar assets or liabilities; quoted prices
in markets that are not active; or other inputs that are observable or can be corroborated by observable market data; and&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0 0 0 0.5in; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0 0 0 0.5in; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Level
3: Significant unobservable inputs that reflect a reporting entity&#x2019;s own assumptions that market participants would use in pricing
an asset or liability.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Cash
and cash equivalents, other current assets, accounts payable and other accrued liabilities are reflected in the condensed consolidated
balance sheet at their approximate estimated fair values primarily due to their short-term nature. The fair values of securities available
for sale is determined by relying on the securities&#x2019; relationship to other benchmark quoted securities and classified its investments
as Level 2 items in both 2021 and 2020. There were no transfers of assets or liabilities between Level 1 and Level 2 and no transfers
in or out of Level 3 during the six-months ended June 30, 2021 or during the year ended December 31, 2020. The changes
in Level 3 liabilities were the result of changes in the fair value of the earn-out milestone liability included in earnings and in-process
R&amp;amp;D. The earnout milestone liability is valued using a risk-adjusted assessment of the probability of payment of each milestone,
discounted to present value using an estimated time to achieve the milestone (see Note 14).&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;




&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p id="xdx_89D_eus-gaap--ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock_z4POuAb1LhXf" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Assets
and liabilities measured at fair value are summarized below:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8B9_zn5uah0SSVHd" style="display: none"&gt;Schedule
of Fair Value, Assets and Liabilities Measured on Recurring Basis&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Total
    Fair Value&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Quoted
    Prices in Active Markets for Identical Assets/Liabilities (Level 1)&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Significant
                                            Other Observable Inputs&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;(Level
                                            2)&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Significant
                                            Unobservable Inputs&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;(Level
                                            3)&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Assets:&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Recurring items as of June 30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="padding-left: 10pt; width: 40%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Investment
    in debt securities - available for sale, at fair value&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98D_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20210630__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FinancialInstrumentAxis__us-gaap--CorporateDebtSecuritiesMember_pp0p0" style="width: 11%; text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;31,923,285&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_983_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20210630__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel1Member__us-gaap--FinancialInstrumentAxis__us-gaap--CorporateDebtSecuritiesMember_pp0p0" style="width: 11%; text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0882"&gt;&#x2013;&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_980_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20210630__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel2Member__us-gaap--FinancialInstrumentAxis__us-gaap--CorporateDebtSecuritiesMember_pp0p0" style="width: 11%; text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;31,923,285&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_981_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20210630__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel3Member__us-gaap--FinancialInstrumentAxis__us-gaap--CorporateDebtSecuritiesMember_pp0p0" style="width: 11%; text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0886"&gt;&#x2013;&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Non-recurring items as of June 30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-left: 10pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;In-process R&amp;amp;D (Note
    9)&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_989_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20210630__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsNonrecurringMember__us-gaap--FinancialInstrumentAxis__custom--InprocessRandDMember_pp0p0" style="text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;13,366,234&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_980_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20210630__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsNonrecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel1Member__us-gaap--FinancialInstrumentAxis__custom--InprocessRandDMember_pp0p0" style="text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0890"&gt;&#x2013;&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_981_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20210630__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsNonrecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel2Member__us-gaap--FinancialInstrumentAxis__custom--InprocessRandDMember_pp0p0" style="text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0892"&gt;&#x2013;&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_986_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20210630__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsNonrecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel3Member__us-gaap--FinancialInstrumentAxis__custom--InprocessRandDMember_pp0p0" style="text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;13,366,234&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Non-recurring items as of December 31, 2020&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="padding-left: 10pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;In-process R&amp;amp;D (Note
    9)&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98C_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20201231__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsNonrecurringMember__us-gaap--FinancialInstrumentAxis__custom--InprocessRandDMember_pp0p0" style="text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;13,366,234&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98C_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20201231__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsNonrecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel1Member__us-gaap--FinancialInstrumentAxis__custom--InprocessRandDMember_pp0p0" style="text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0898"&gt;&#x2013;&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_982_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20201231__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsNonrecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel2Member__us-gaap--FinancialInstrumentAxis__custom--InprocessRandDMember_pp0p0" style="text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0900"&gt;&#x2013;&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_983_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20201231__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsNonrecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel3Member__us-gaap--FinancialInstrumentAxis__custom--InprocessRandDMember_pp0p0" style="text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;13,366,234&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Liabilities:&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Recurring items as of June 30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-left: 10pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Earn-out milestone liability
    (Note 14)&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_982_eus-gaap--BusinessCombinationContingentConsiderationLiabilityNoncurrent_c20210630__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember_pp0p0" style="text-align: right" title="Earn-out milestone liability"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;7,088,000&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_983_eus-gaap--BusinessCombinationContingentConsiderationLiabilityNoncurrent_c20210630__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel1Member_pp0p0" style="text-align: right" title="Earn-out milestone liability"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0906"&gt;&#x2013;&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_982_eus-gaap--BusinessCombinationContingentConsiderationLiabilityNoncurrent_c20210630__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel2Member_pp0p0" style="text-align: right" title="Earn-out milestone liability"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0908"&gt;&#x2013;&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_981_eus-gaap--BusinessCombinationContingentConsiderationLiabilityNoncurrent_c20210630__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel3Member_pp0p0" style="text-align: right" title="Earn-out milestone liability"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;7,088,000&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Recurring items as of December 31, 2020&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="padding-left: 10pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Earn-out milestone liability
    (Note 14)&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_987_eus-gaap--BusinessCombinationContingentConsiderationLiabilityNoncurrent_c20201231__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember_pp0p0" style="text-align: right" title="Earn-out milestone liability"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;7,018,000&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98F_eus-gaap--BusinessCombinationContingentConsiderationLiabilityNoncurrent_c20201231__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel1Member_pp0p0" style="text-align: right" title="Earn-out milestone liability"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0914"&gt;&#x2013;&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98C_eus-gaap--BusinessCombinationContingentConsiderationLiabilityNoncurrent_c20201231__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel2Member_pp0p0" style="text-align: right" title="Earn-out milestone liability"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0916"&gt;&#x2013;&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98D_eus-gaap--BusinessCombinationContingentConsiderationLiabilityNoncurrent_c20201231__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel3Member_pp0p0" style="text-align: right" title="Earn-out milestone liability"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;7,018,000&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p id="xdx_8A1_z2PtZt8SCfn" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

</us-gaap:DerivativesAndFairValueTextBlock>
    <us-gaap:ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock contextRef="From2021-01-01to2021-06-30">&lt;p id="xdx_89D_eus-gaap--ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock_z4POuAb1LhXf" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Assets
and liabilities measured at fair value are summarized below:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8B9_zn5uah0SSVHd" style="display: none"&gt;Schedule
of Fair Value, Assets and Liabilities Measured on Recurring Basis&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Total
    Fair Value&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Quoted
    Prices in Active Markets for Identical Assets/Liabilities (Level 1)&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Significant
                                            Other Observable Inputs&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;(Level
                                            2)&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Significant
                                            Unobservable Inputs&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;(Level
                                            3)&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Assets:&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Recurring items as of June 30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="padding-left: 10pt; width: 40%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Investment
    in debt securities - available for sale, at fair value&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98D_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20210630__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FinancialInstrumentAxis__us-gaap--CorporateDebtSecuritiesMember_pp0p0" style="width: 11%; text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;31,923,285&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_983_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20210630__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel1Member__us-gaap--FinancialInstrumentAxis__us-gaap--CorporateDebtSecuritiesMember_pp0p0" style="width: 11%; text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0882"&gt;&#x2013;&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_980_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20210630__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel2Member__us-gaap--FinancialInstrumentAxis__us-gaap--CorporateDebtSecuritiesMember_pp0p0" style="width: 11%; text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;31,923,285&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_981_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20210630__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel3Member__us-gaap--FinancialInstrumentAxis__us-gaap--CorporateDebtSecuritiesMember_pp0p0" style="width: 11%; text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0886"&gt;&#x2013;&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Non-recurring items as of June 30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-left: 10pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;In-process R&amp;amp;D (Note
    9)&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_989_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20210630__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsNonrecurringMember__us-gaap--FinancialInstrumentAxis__custom--InprocessRandDMember_pp0p0" style="text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;13,366,234&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_980_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20210630__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsNonrecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel1Member__us-gaap--FinancialInstrumentAxis__custom--InprocessRandDMember_pp0p0" style="text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0890"&gt;&#x2013;&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_981_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20210630__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsNonrecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel2Member__us-gaap--FinancialInstrumentAxis__custom--InprocessRandDMember_pp0p0" style="text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0892"&gt;&#x2013;&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_986_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20210630__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsNonrecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel3Member__us-gaap--FinancialInstrumentAxis__custom--InprocessRandDMember_pp0p0" style="text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;13,366,234&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Non-recurring items as of December 31, 2020&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="padding-left: 10pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;In-process R&amp;amp;D (Note
    9)&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98C_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20201231__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsNonrecurringMember__us-gaap--FinancialInstrumentAxis__custom--InprocessRandDMember_pp0p0" style="text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;13,366,234&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98C_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20201231__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsNonrecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel1Member__us-gaap--FinancialInstrumentAxis__custom--InprocessRandDMember_pp0p0" style="text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0898"&gt;&#x2013;&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_982_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20201231__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsNonrecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel2Member__us-gaap--FinancialInstrumentAxis__custom--InprocessRandDMember_pp0p0" style="text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0900"&gt;&#x2013;&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_983_eus-gaap--AvailableForSaleSecuritiesDebtSecuritiesCurrent_c20201231__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsNonrecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel3Member__us-gaap--FinancialInstrumentAxis__custom--InprocessRandDMember_pp0p0" style="text-align: right" title="Investment securities, available for sale"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;13,366,234&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Liabilities:&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Recurring items as of June 30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-left: 10pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Earn-out milestone liability
    (Note 14)&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_982_eus-gaap--BusinessCombinationContingentConsiderationLiabilityNoncurrent_c20210630__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember_pp0p0" style="text-align: right" title="Earn-out milestone liability"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;7,088,000&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_983_eus-gaap--BusinessCombinationContingentConsiderationLiabilityNoncurrent_c20210630__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel1Member_pp0p0" style="text-align: right" title="Earn-out milestone liability"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0906"&gt;&#x2013;&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_982_eus-gaap--BusinessCombinationContingentConsiderationLiabilityNoncurrent_c20210630__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel2Member_pp0p0" style="text-align: right" title="Earn-out milestone liability"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0908"&gt;&#x2013;&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_981_eus-gaap--BusinessCombinationContingentConsiderationLiabilityNoncurrent_c20210630__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel3Member_pp0p0" style="text-align: right" title="Earn-out milestone liability"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;7,088,000&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Recurring items as of December 31, 2020&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="padding-left: 10pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Earn-out milestone liability
    (Note 14)&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_987_eus-gaap--BusinessCombinationContingentConsiderationLiabilityNoncurrent_c20201231__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember_pp0p0" style="text-align: right" title="Earn-out milestone liability"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;7,018,000&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98F_eus-gaap--BusinessCombinationContingentConsiderationLiabilityNoncurrent_c20201231__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel1Member_pp0p0" style="text-align: right" title="Earn-out milestone liability"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0914"&gt;&#x2013;&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98C_eus-gaap--BusinessCombinationContingentConsiderationLiabilityNoncurrent_c20201231__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel2Member_pp0p0" style="text-align: right" title="Earn-out milestone liability"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0916"&gt;&#x2013;&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98D_eus-gaap--BusinessCombinationContingentConsiderationLiabilityNoncurrent_c20201231__us-gaap--FairValueByMeasurementFrequencyAxis__us-gaap--FairValueMeasurementsRecurringMember__us-gaap--FairValueByFairValueHierarchyLevelAxis__us-gaap--FairValueInputsLevel3Member_pp0p0" style="text-align: right" title="Earn-out milestone liability"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;7,018,000&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

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    <us-gaap:IntangibleAssetsDisclosureTextBlock contextRef="From2021-01-01to2021-06-30">&lt;p id="xdx_804_eus-gaap--IntangibleAssetsDisclosureTextBlock_zzoxOLipmjol" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
9. &lt;span id="xdx_822_zYNgm3e1UdA8"&gt;Intangible Assets&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;In
June 2014, we completed the acquisition of substantially all of the assets of EGEN, Inc., an Alabama corporation, which has changed its
company name to EGWU, Inc. after the closing of the acquisition (&#x201c;EGEN&#x201d;). We acquired all of EGEN&#x2019;s right, title and
interest in and to substantially all of the assets of EGEN, including cash and cash equivalents, patents, trademarks and other intellectual
property rights, clinical data, certain contracts, licenses and permits, equipment, furniture, office equipment, furnishings, supplies
and other tangible personal property. In addition, CLSN Laboratories assumed certain specified liabilities of EGEN, including the liabilities
arising out of the acquired contracts and other assets relating to periods after the closing date.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;i&gt;Acquired
In-process Research and Development&lt;/i&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Acquired
in-process research and development (IPR&amp;amp;D) consists of EGEN&#x2019;s drug technology platforms: TheraPlas and TheraSilence. The fair
value of the IPR&amp;amp;D drug technology platforms was estimated to be $&lt;span id="xdx_909_eus-gaap--IndefinitelivedIntangibleAssetsAcquired_pn5n6_c20210101__20210630__us-gaap--BusinessAcquisitionAxis__custom--EGENIncMember__dei--LegalEntityAxis__custom--IPRAndDDrugTechnologyPlatformsMember_zPvuzEz64MBa"&gt;24.2
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million as of the acquisition date. As of the
closing of the acquisition, the IPR&amp;amp;D was considered indefinite lived intangible assets and will not be amortized. IPR&amp;amp;D is reviewed
for impairment at least annually as of our third quarter ended September 30, and whenever events or changes in circumstances indicate
that the carrying value of the assets might not be recoverable. The Company&#x2019;s IPR&amp;amp;D consisted of three core elements, its RNA
delivery system, its glioblastoma multiforme cancer (GBM) product candidate and its ovarian cancer indication.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
Company&#x2019;s ovarian cancer indication, with original value of $&lt;span id="xdx_906_eus-gaap--FinitelivedIntangibleAssetsAcquired1_pn5n6_c20210101__20210630__dei--LegalEntityAxis__custom--IPRAndDDrugTechnologyPlatformsMember__us-gaap--ContingentConsiderationByTypeAxis__custom--OvarianCancerMember_z1ajCb1WHJab"&gt;13.3
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million has not been impaired since its acquisition.
At September 30, 2020, the Company evaluated its IPR&amp;amp;D of the ovarian cancer indication and concluded that it is not more likely
than not that the asset is impaired. As no other indicators of impairment existed during the fourth quarter of 2020 or first half of
2021, &lt;span id="xdx_902_eus-gaap--AssetImpairmentCharges_pp0p0_do_c20200101__20200630__dei--LegalEntityAxis__custom--IPRAndDDrugTechnologyPlatformsMember_zJ7zEOjzxcC2"&gt;no
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;impairment charges were recorded during the three
or six-months ended June 30, 2021 and 2020.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
Company&#x2019;s GBM candidate, with original value of $&lt;span id="xdx_906_eus-gaap--AssetImpairmentCharges_pn5n6_c20180101__20181231__us-gaap--BusinessAcquisitionAxis__custom--EGENIncMember__us-gaap--ContingentConsiderationByTypeAxis__custom--GlioblastomaMultiformeBrainCancerMember_zaIkrUUgDVj1"&gt;9.4
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million had cumulative impairments through 2018
of $&lt;span id="xdx_90C_eus-gaap--AssetImpairmentCharges_pn6n6_c20180101__20181231__us-gaap--BusinessAcquisitionAxis__custom--EGENIncMember_zgFV6MHTYqJ9"&gt;7
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million, with remaining carrying value of $&lt;span id="xdx_909_eus-gaap--AssetImpairmentCharges_pn5n6_c20190101__20191231__us-gaap--ContingentConsiderationByTypeAxis__custom--GlioblastomaMultiformeBrainCancerMember_zM9mLehGFYvb"&gt;2.4
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million at December 31, 2019. On September 30,
2020, the Company evaluated its IPR&amp;amp;D for the (GBM) product candidate and concluded that it is more likely than not that the asset
is further impaired. After this assessment on September 30, 2020, the Company wrote off the remaining $&lt;span id="xdx_907_eus-gaap--AssetImpairmentCharges_pn5n6_c20200929__20200930__us-gaap--BusinessAcquisitionAxis__custom--EGENIncMember__us-gaap--ContingentConsiderationByTypeAxis__custom--GlioblastomaMultiformeBrainCancerMember_zhIpPkbMlpC8"&gt;2.4
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million of this asset, thereby recognizing a
non-cash charge of $&lt;span id="xdx_90F_ecustom--NoncashCharge_pn5n6_c20200701__20200930__us-gaap--BusinessAcquisitionAxis__custom--EGENIncMember__us-gaap--ContingentConsiderationByTypeAxis__custom--GlioblastomaMultiformeBrainCancerMember_zlGEsTTp0Mjh"&gt;2.4
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million in the third quarter of 2020.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;




&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;i&gt;&#160;&lt;/i&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;i&gt;Covenants
Not to Compete&lt;/i&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Pursuant
to the EGEN Purchase Agreement, EGEN provided certain covenants (&#x201c;Covenant Not To Compete&#x201d;) to the Company whereby EGEN agreed,
during the period ending on the seventh anniversary of the closing date of the acquisition on June 20, 2014, not to enter into any business,
directly or indirectly, which competes with the business of the Company nor will it contact, solicit or approach any of the employees
of the Company for purposes of offering employment. The Covenant Not to Compete which was valued at approximately $&lt;span id="xdx_90F_eus-gaap--FinitelivedIntangibleAssetsAcquired1_pn5n6_c20210101__20210630__us-gaap--BusinessAcquisitionAxis__custom--EGENIncMember__us-gaap--TypeOfArrangementAxis__custom--PurchaseAgreementMember_zElAFzn39hja"&gt;1.6
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million at the date of the EGEN acquisition has
a definitive life and is amortized on a straight-line basis over its life of &lt;span id="xdx_90D_eus-gaap--FiniteLivedIntangibleAssetUsefulLife_dtY_c20210101__20210630__us-gaap--BusinessAcquisitionAxis__custom--EGENIncMember__us-gaap--TypeOfArrangementAxis__custom--PurchaseAgreementMember_zPPMeop8zcDl"&gt;7
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;years. The Company recognized amortization expense
of $&lt;span id="xdx_90B_eus-gaap--AdjustmentForAmortization_c20200101__20200630__us-gaap--BusinessAcquisitionAxis__custom--EGENIncMember__us-gaap--TypeOfArrangementAxis__custom--PurchaseAgreementMember_zyI2tWwnXl1e"&gt;56,830
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;in each of the three and six-month periods ended
June 30, 2021 and 2020. The carrying value of the Covenant Not to Compete was fully amortized as of June 30, 2021 and $&lt;span id="xdx_90E_eus-gaap--FiniteLivedIntangibleAssetsNet_c20201231__us-gaap--TypeOfArrangementAxis__custom--AspirePurchaseAgreementsMember_pp0p0"&gt;113,660&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;,
net of $&lt;span id="xdx_90C_eus-gaap--FiniteLivedIntangibleAssetsAccumulatedAmortization_c20201231__us-gaap--TypeOfArrangementAxis__custom--AspirePurchaseAgreementsMember_pp0p0"&gt;1,477,554
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;accumulated amortization, as of December 31,
2020.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;i&gt;Goodwill&lt;/i&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
purchase price exceeded the estimated fair value of the net assets acquired by approximately $&lt;span id="xdx_909_eus-gaap--GoodwillAcquiredDuringPeriod_pn5n6_c20210101__20210630__us-gaap--BusinessAcquisitionAxis__custom--EGENIncMember_z3Tt7kqvnD75"&gt;2.0
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million which was recorded as Goodwill. Goodwill
represents the difference between the total purchase price for the net assets purchased from EGEN and the aggregate fair values of tangible
and intangible assets acquired, less liabilities assumed. Goodwill is reviewed for impairment at least annually as of our third quarter
ended September 30 or sooner if we believe indicators of impairment exist. As of June 30, 2021, we concluded that the Company&#x2019;s
fair value exceeded its carrying value therefore &#x201c;it is not more likely than not&#x201d; that the Goodwill was impaired.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p id="xdx_894_eus-gaap--FiniteLivedAndIndefiniteLivedIntangibleAssetsAcquiredAsPartOfBusinessCombinationTableTextBlock_zdYgJeGkoxUh" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Following
is a summary of the net fair value of the assets acquired in the EGEN asset acquisition for the six-month period ended June 30,
2021:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8BB_ztRGk8i77Aa6" style="display: none"&gt;Schedule
of Fair Value of Assets Acquired&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;IPR&amp;amp;D&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Goodwill&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Covenant
    Not To Compete&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;For the six-months ended June 30,
    2021&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="width: 46%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Balance at January 1, 2021, net&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_986_eus-gaap--FiniteLivedIntangibleAssetsNet_iS_pp0p0_c20210101__20210630__us-gaap--FairValueByAssetClassAxis__custom--IPRAndDMember_zjQ3JIkxxDj7" style="width: 14%; text-align: right" title="Intangible assets, beginning balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;13,366,234&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98E_eus-gaap--FiniteLivedIntangibleAssetsNet_iS_pp0p0_c20210101__20210630__us-gaap--FairValueByAssetClassAxis__us-gaap--GoodwillMember_zNBWiGj7paVi" style="width: 14%; text-align: right" title="Intangible assets, beginning balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;1,976,101&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98E_eus-gaap--FiniteLivedIntangibleAssetsNet_iS_pp0p0_c20210101__20210630__us-gaap--FiniteLivedIntangibleAssetsByMajorClassAxis__us-gaap--NoncompeteAgreementsMember_zdqB8nlRBX59" style="width: 14%; text-align: right" title="Intangible assets, beginning balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;113,660&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Amortization&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_986_eus-gaap--AmortizationOfIntangibleAssets_iN_pp0p0_di_c20210101__20210630__us-gaap--FairValueByAssetClassAxis__custom--IPRAndDMember_z7TzeeSXjI5a" style="border-bottom: Black 1.5pt solid; text-align: right" title="Amortization"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0944"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98D_eus-gaap--AmortizationOfIntangibleAssets_iN_pp0p0_di_c20210101__20210630__us-gaap--FairValueByAssetClassAxis__us-gaap--GoodwillMember_zjtx3T7G2Lgi" style="border-bottom: Black 1.5pt solid; text-align: right" title="Amortization"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0946"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_982_eus-gaap--AmortizationOfIntangibleAssets_iN_pp0p0_di_c20210101__20210630__us-gaap--FiniteLivedIntangibleAssetsByMajorClassAxis__us-gaap--NoncompeteAgreementsMember_zNQ4n0vGQP99" style="border-bottom: Black 1.5pt solid; text-align: right" title="Amortization"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;(113,660&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;)&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Balance at June 30,
    2021, net&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98A_eus-gaap--FiniteLivedIntangibleAssetsNet_iE_pp0p0_c20210101__20210630__us-gaap--FairValueByAssetClassAxis__custom--IPRAndDMember_zZEW29lairU1" style="border-bottom: Black 2.5pt double; text-align: right" title="Intangible assets, ending balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;13,366,234&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_983_eus-gaap--FiniteLivedIntangibleAssetsNet_iE_pp0p0_c20210101__20210630__us-gaap--FairValueByAssetClassAxis__us-gaap--GoodwillMember_z0nQAbP1KtYl" style="border-bottom: Black 2.5pt double; text-align: right" title="Intangible assets, ending balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;1,976,101&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98F_eus-gaap--FiniteLivedIntangibleAssetsNet_iE_pp0p0_c20210101__20210630__us-gaap--FiniteLivedIntangibleAssetsByMajorClassAxis__us-gaap--NoncompeteAgreementsMember_zr55ihcRj1a4" style="border-bottom: Black 2.5pt double; text-align: right" title="Intangible assets, ending balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0954"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p id="xdx_8A4_z0domUgEPXS2" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

</us-gaap:IntangibleAssetsDisclosureTextBlock>
    <us-gaap:IndefinitelivedIntangibleAssetsAcquired
      contextRef="From2021-01-012021-06-30_custom_EGENIncMember_custom_IPRAndDDrugTechnologyPlatformsMember"
      decimals="-5"
      unitRef="USD">24200000</us-gaap:IndefinitelivedIntangibleAssetsAcquired>
    <us-gaap:FinitelivedIntangibleAssetsAcquired1
      contextRef="From2021-01-012021-06-30_custom_IPRAndDDrugTechnologyPlatformsMember_custom_OvarianCancerMember"
      decimals="-5"
      unitRef="USD">13300000</us-gaap:FinitelivedIntangibleAssetsAcquired1>
    <us-gaap:AssetImpairmentCharges
      contextRef="From2018-01-012018-12-31_custom_EGENIncMember_custom_GlioblastomaMultiformeBrainCancerMember"
      decimals="-5"
      unitRef="USD">9400000</us-gaap:AssetImpairmentCharges>
    <us-gaap:AssetImpairmentCharges
      contextRef="From2018-01-012018-12-31_custom_EGENIncMember"
      decimals="-6"
      unitRef="USD">7000000</us-gaap:AssetImpairmentCharges>
    <us-gaap:AssetImpairmentCharges
      contextRef="From2019-01-012019-12-31_custom_GlioblastomaMultiformeBrainCancerMember"
      decimals="-5"
      unitRef="USD">2400000</us-gaap:AssetImpairmentCharges>
    <us-gaap:AssetImpairmentCharges
      contextRef="From2020-09-292020-09-30_custom_EGENIncMember_custom_GlioblastomaMultiformeBrainCancerMember"
      decimals="-5"
      unitRef="USD">2400000</us-gaap:AssetImpairmentCharges>
    <CLSN:NoncashCharge
      contextRef="From2020-07-012020-09-30_custom_EGENIncMember_custom_GlioblastomaMultiformeBrainCancerMember"
      decimals="-5"
      unitRef="USD">2400000</CLSN:NoncashCharge>
    <us-gaap:FinitelivedIntangibleAssetsAcquired1
      contextRef="From2021-01-012021-06-30_custom_EGENIncMember_custom_PurchaseAgreementMember"
      decimals="-5"
      unitRef="USD">1600000</us-gaap:FinitelivedIntangibleAssetsAcquired1>
    <us-gaap:FiniteLivedIntangibleAssetUsefulLife contextRef="From2021-01-012021-06-30_custom_EGENIncMember_custom_PurchaseAgreementMember">P7Y</us-gaap:FiniteLivedIntangibleAssetUsefulLife>
    <us-gaap:AdjustmentForAmortization
      contextRef="From2020-01-012020-06-30_custom_EGENIncMember_custom_PurchaseAgreementMember"
      decimals="0"
      unitRef="USD">56830</us-gaap:AdjustmentForAmortization>
    <us-gaap:FiniteLivedIntangibleAssetsNet
      contextRef="AsOf2020-12-31_custom_AspirePurchaseAgreementsMember"
      decimals="0"
      unitRef="USD">113660</us-gaap:FiniteLivedIntangibleAssetsNet>
    <us-gaap:FiniteLivedIntangibleAssetsAccumulatedAmortization
      contextRef="AsOf2020-12-31_custom_AspirePurchaseAgreementsMember"
      decimals="0"
      unitRef="USD">1477554</us-gaap:FiniteLivedIntangibleAssetsAccumulatedAmortization>
    <us-gaap:GoodwillAcquiredDuringPeriod
      contextRef="From2021-01-012021-06-30_custom_EGENIncMember"
      decimals="-5"
      unitRef="USD">2000000.0</us-gaap:GoodwillAcquiredDuringPeriod>
    <us-gaap:FiniteLivedAndIndefiniteLivedIntangibleAssetsAcquiredAsPartOfBusinessCombinationTableTextBlock contextRef="From2021-01-01to2021-06-30">&lt;p id="xdx_894_eus-gaap--FiniteLivedAndIndefiniteLivedIntangibleAssetsAcquiredAsPartOfBusinessCombinationTableTextBlock_zdYgJeGkoxUh" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Following
is a summary of the net fair value of the assets acquired in the EGEN asset acquisition for the six-month period ended June 30,
2021:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8BB_ztRGk8i77Aa6" style="display: none"&gt;Schedule
of Fair Value of Assets Acquired&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;IPR&amp;amp;D&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Goodwill&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Covenant
    Not To Compete&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;For the six-months ended June 30,
    2021&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="width: 46%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Balance at January 1, 2021, net&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_986_eus-gaap--FiniteLivedIntangibleAssetsNet_iS_pp0p0_c20210101__20210630__us-gaap--FairValueByAssetClassAxis__custom--IPRAndDMember_zjQ3JIkxxDj7" style="width: 14%; text-align: right" title="Intangible assets, beginning balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;13,366,234&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98E_eus-gaap--FiniteLivedIntangibleAssetsNet_iS_pp0p0_c20210101__20210630__us-gaap--FairValueByAssetClassAxis__us-gaap--GoodwillMember_zNBWiGj7paVi" style="width: 14%; text-align: right" title="Intangible assets, beginning balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;1,976,101&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98E_eus-gaap--FiniteLivedIntangibleAssetsNet_iS_pp0p0_c20210101__20210630__us-gaap--FiniteLivedIntangibleAssetsByMajorClassAxis__us-gaap--NoncompeteAgreementsMember_zdqB8nlRBX59" style="width: 14%; text-align: right" title="Intangible assets, beginning balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;113,660&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Amortization&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_986_eus-gaap--AmortizationOfIntangibleAssets_iN_pp0p0_di_c20210101__20210630__us-gaap--FairValueByAssetClassAxis__custom--IPRAndDMember_z7TzeeSXjI5a" style="border-bottom: Black 1.5pt solid; text-align: right" title="Amortization"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0944"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98D_eus-gaap--AmortizationOfIntangibleAssets_iN_pp0p0_di_c20210101__20210630__us-gaap--FairValueByAssetClassAxis__us-gaap--GoodwillMember_zjtx3T7G2Lgi" style="border-bottom: Black 1.5pt solid; text-align: right" title="Amortization"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0946"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_982_eus-gaap--AmortizationOfIntangibleAssets_iN_pp0p0_di_c20210101__20210630__us-gaap--FiniteLivedIntangibleAssetsByMajorClassAxis__us-gaap--NoncompeteAgreementsMember_zNQ4n0vGQP99" style="border-bottom: Black 1.5pt solid; text-align: right" title="Amortization"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;(113,660&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;)&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Balance at June 30,
    2021, net&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98A_eus-gaap--FiniteLivedIntangibleAssetsNet_iE_pp0p0_c20210101__20210630__us-gaap--FairValueByAssetClassAxis__custom--IPRAndDMember_zZEW29lairU1" style="border-bottom: Black 2.5pt double; text-align: right" title="Intangible assets, ending balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;13,366,234&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_983_eus-gaap--FiniteLivedIntangibleAssetsNet_iE_pp0p0_c20210101__20210630__us-gaap--FairValueByAssetClassAxis__us-gaap--GoodwillMember_z0nQAbP1KtYl" style="border-bottom: Black 2.5pt double; text-align: right" title="Intangible assets, ending balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;1,976,101&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98F_eus-gaap--FiniteLivedIntangibleAssetsNet_iE_pp0p0_c20210101__20210630__us-gaap--FiniteLivedIntangibleAssetsByMajorClassAxis__us-gaap--NoncompeteAgreementsMember_zr55ihcRj1a4" style="border-bottom: Black 2.5pt double; text-align: right" title="Intangible assets, ending balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0954"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

</us-gaap:FiniteLivedAndIndefiniteLivedIntangibleAssetsAcquiredAsPartOfBusinessCombinationTableTextBlock>
    <us-gaap:FiniteLivedIntangibleAssetsNet
      contextRef="AsOf2020-12-31_custom_IPRAndDMember"
      decimals="0"
      unitRef="USD">13366234</us-gaap:FiniteLivedIntangibleAssetsNet>
    <us-gaap:FiniteLivedIntangibleAssetsNet
      contextRef="AsOf2020-12-31_us-gaap_GoodwillMember"
      decimals="0"
      unitRef="USD">1976101</us-gaap:FiniteLivedIntangibleAssetsNet>
    <us-gaap:FiniteLivedIntangibleAssetsNet
      contextRef="AsOf2020-12-31_us-gaap_NoncompeteAgreementsMember"
      decimals="0"
      unitRef="USD">113660</us-gaap:FiniteLivedIntangibleAssetsNet>
    <us-gaap:AmortizationOfIntangibleAssets
      contextRef="From2021-01-012021-06-30_us-gaap_NoncompeteAgreementsMember"
      decimals="0"
      unitRef="USD">113660</us-gaap:AmortizationOfIntangibleAssets>
    <us-gaap:FiniteLivedIntangibleAssetsNet
      contextRef="AsOf2021-06-30_custom_IPRAndDMember"
      decimals="0"
      unitRef="USD">13366234</us-gaap:FiniteLivedIntangibleAssetsNet>
    <us-gaap:FiniteLivedIntangibleAssetsNet
      contextRef="AsOf2021-06-30_us-gaap_GoodwillMember"
      decimals="0"
      unitRef="USD">1976101</us-gaap:FiniteLivedIntangibleAssetsNet>
    <us-gaap:AccountsPayableAndAccruedLiabilitiesDisclosureTextBlock contextRef="From2021-01-01to2021-06-30">&lt;p id="xdx_800_eus-gaap--AccountsPayableAndAccruedLiabilitiesDisclosureTextBlock_zhhv59cbBNC1" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
10. &lt;span id="xdx_82A_z0L6k1aaQbsc"&gt;Accrued Liabilities&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p id="xdx_89D_eus-gaap--ScheduleOfAccruedLiabilitiesTableTextBlock_zOGA1Tqnz419" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Other
accrued liabilities at June 30, 2021 and December 31, 2020 include the following:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8BB_zWfJZ5aHNoz4" style="display: none"&gt;Schedule
of Accrued Liabilities&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_497_20210630_z2FDEw1SRoAa" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;June
    30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_493_20201231_zBnTiuJAFtpg" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;December
    31, 2020&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_401_eus-gaap--ContractualObligation_iI_pp0p0_maALCz6Sz_zfyfKVfsRMK4" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 60%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Amounts due to contract research
    organizations and other contractual agreements&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;1,189,017&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;636,000&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40B_eus-gaap--EmployeeRelatedLiabilitiesCurrent_iI_pp0p0_maALCz6Sz_zDGQRpcFS3Gf" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Accrued payroll and related benefits&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;1,016,610&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;1,736,271&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40F_eus-gaap--AccruedProfessionalFeesCurrent_iI_pp0p0_maALCz6Sz_zPrELNiZ4yrf" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Accrued professional fees&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;80,625&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;66,850&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40E_eus-gaap--InterestPayableCurrent_iI_pp0p0_maALCz6Sz_z3zsLNxSna9" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Accrued interest&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;7,042&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0970"&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;-&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40A_eus-gaap--OtherAccruedLiabilitiesCurrent_iI_pp0p0_maALCz6Sz_zpNKibQdMIa3" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Other&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;19,411&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;19,411&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40B_eus-gaap--AccruedLiabilitiesCurrent_iTI_pp0p0_mtALCz6Sz_zGuQO0aCjIf1" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Total&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2,312,705&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2,458,532&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p id="xdx_8A7_zIUS3GKp6Zrf" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

</us-gaap:AccountsPayableAndAccruedLiabilitiesDisclosureTextBlock>
    <us-gaap:ScheduleOfAccruedLiabilitiesTableTextBlock contextRef="From2021-01-01to2021-06-30">&lt;p id="xdx_89D_eus-gaap--ScheduleOfAccruedLiabilitiesTableTextBlock_zOGA1Tqnz419" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Other
accrued liabilities at June 30, 2021 and December 31, 2020 include the following:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8BB_zWfJZ5aHNoz4" style="display: none"&gt;Schedule
of Accrued Liabilities&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_497_20210630_z2FDEw1SRoAa" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;June
    30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_493_20201231_zBnTiuJAFtpg" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;December
    31, 2020&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_401_eus-gaap--ContractualObligation_iI_pp0p0_maALCz6Sz_zfyfKVfsRMK4" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 60%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Amounts due to contract research
    organizations and other contractual agreements&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;1,189,017&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;636,000&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40B_eus-gaap--EmployeeRelatedLiabilitiesCurrent_iI_pp0p0_maALCz6Sz_zDGQRpcFS3Gf" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Accrued payroll and related benefits&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;1,016,610&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;1,736,271&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40F_eus-gaap--AccruedProfessionalFeesCurrent_iI_pp0p0_maALCz6Sz_zPrELNiZ4yrf" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Accrued professional fees&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;80,625&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;66,850&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40E_eus-gaap--InterestPayableCurrent_iI_pp0p0_maALCz6Sz_z3zsLNxSna9" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Accrued interest&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;7,042&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0970"&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;-&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40A_eus-gaap--OtherAccruedLiabilitiesCurrent_iI_pp0p0_maALCz6Sz_zpNKibQdMIa3" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Other&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;19,411&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;19,411&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40B_eus-gaap--AccruedLiabilitiesCurrent_iTI_pp0p0_mtALCz6Sz_zGuQO0aCjIf1" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Total&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2,312,705&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2,458,532&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

</us-gaap:ScheduleOfAccruedLiabilitiesTableTextBlock>
    <us-gaap:ContractualObligation contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">1189017</us-gaap:ContractualObligation>
    <us-gaap:ContractualObligation contextRef="AsOf2020-12-31" decimals="0" unitRef="USD">636000</us-gaap:ContractualObligation>
    <us-gaap:EmployeeRelatedLiabilitiesCurrent contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">1016610</us-gaap:EmployeeRelatedLiabilitiesCurrent>
    <us-gaap:EmployeeRelatedLiabilitiesCurrent contextRef="AsOf2020-12-31" decimals="0" unitRef="USD">1736271</us-gaap:EmployeeRelatedLiabilitiesCurrent>
    <us-gaap:AccruedProfessionalFeesCurrent contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">80625</us-gaap:AccruedProfessionalFeesCurrent>
    <us-gaap:AccruedProfessionalFeesCurrent contextRef="AsOf2020-12-31" decimals="0" unitRef="USD">66850</us-gaap:AccruedProfessionalFeesCurrent>
    <us-gaap:InterestPayableCurrent contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">7042</us-gaap:InterestPayableCurrent>
    <us-gaap:OtherAccruedLiabilitiesCurrent contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">19411</us-gaap:OtherAccruedLiabilitiesCurrent>
    <us-gaap:OtherAccruedLiabilitiesCurrent contextRef="AsOf2020-12-31" decimals="0" unitRef="USD">19411</us-gaap:OtherAccruedLiabilitiesCurrent>
    <us-gaap:AccruedLiabilitiesCurrent contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">2312705</us-gaap:AccruedLiabilitiesCurrent>
    <us-gaap:AccruedLiabilitiesCurrent contextRef="AsOf2020-12-31" decimals="0" unitRef="USD">2458532</us-gaap:AccruedLiabilitiesCurrent>
    <us-gaap:DebtDisclosureTextBlock contextRef="From2021-01-01to2021-06-30">&lt;p id="xdx_804_eus-gaap--DebtDisclosureTextBlock_zDBsHBsTvYFi" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
11. &lt;span id="xdx_82D_ztfCNB3BF8f6"&gt;Notes&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;b&gt; &lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Payable&lt;/span&gt;&lt;/b&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;i&gt;The
SVB Loan Facility&lt;/i&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
June 18, 2021, the Company entered into a $&lt;span id="xdx_906_eus-gaap--LineOfCreditFacilityMaximumBorrowingCapacity_iI_pn6n6_c20210618__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_zYrRHKx65IX7"&gt;10
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million loan facility (the &#x201c;SVB Loan Facility&#x201d;)
with Silicon Valley Bank (&#x201c;SVB&#x201d;). Celsion immediately used $&lt;span id="xdx_90E_eus-gaap--ProceedsFromLinesOfCredit_pn6n6_c20210601__20210618__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_zRkqre0767zc"&gt;6
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million from the SVB Loan Facility to
retire all outstanding indebtedness with Horizon Technology Finance Corporation as further discussed below. Simultaneously with this
transaction, the Company used $&lt;span id="xdx_909_eus-gaap--RestrictedCash_iI_pn6n6_c20210618__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_zs9sNYlNZnDk" title="Restricted cash"&gt;6.0&lt;/span&gt; million of other available funds to establish a restricted cash account which serves as security for
the SVB Loan Facility. The remaining $&lt;span id="xdx_900_eus-gaap--LineOfCreditFacilityRemainingBorrowingCapacity_iI_pn6n6_c20210618__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_zXeMk2yvXKAe"&gt;4
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million will be available to be drawn down up
to 12 months after closing and will be used for working capital and to fund the advancement of the Company&#x2019;s product pipeline,
including GEN-1 for the treatment of newly diagnosed advanced ovarian cancer, as well as other strategic initiatives intended to broaden
its product pipeline.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;




&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
SVB Loan Facility is in the form of money market secured indebtedness bearing interest at a calculated WSJ Prime-based variable rate
(currently &lt;span id="xdx_901_eus-gaap--DebtInstrumentInterestRateStatedPercentage_c20210618__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_pdd"&gt;3.25%&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;).
A final payment equal to &lt;span id="xdx_907_ecustom--FinalPaymentPercentage_c20210618__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_pdd"&gt;3%
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;of the total $&lt;span id="xdx_901_eus-gaap--LineOfCredit_iI_pn6n6_c20210618__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_zDU3ysiKCWwa"&gt;10
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million commitment amount is due upon maturity
or prepayment of the SVB Loan Facility. There was &lt;span id="xdx_902_eus-gaap--LineOfCreditFacilityCommitmentFeeAmount_pp0p0_do_c20210601__20210618__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_z7RDcVIvd7nc"&gt;no
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;facility commitment fee and &lt;span id="xdx_908_eus-gaap--DebtConversionConvertedInstrumentWarrantsOrOptionsIssued1_do_c20210601__20210618__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_zxKtZQl2MNTj"&gt;no
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;stock or warrants were issued to SVB. &lt;span id="xdx_903_eus-gaap--DebtInstrumentDescription_c20210601__20210618__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember"&gt;Payments
under the loan agreement are interest only for the first 24 months after loan closing, followed by a 24-month amortization period of
principal and interest through the scheduled maturity date.&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;In
connection with the SVB Loan Facility, the Company incurred financing fees and expenses totaling $&lt;span id="xdx_90D_eus-gaap--InterestAndDebtExpense_c20210601__20210618__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_pp0p0"&gt;243,370
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;which is recorded and classified as debt discount
and are being amortized as interest expense using the effective interest method over the life of the loan. Also, in connection with the
SVB Loan Facility, the Company is required to pay an end-of-term fee equal to &lt;span id="xdx_90C_ecustom--EndOfTermChargePercentage_c20210601__20210618__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_pdd"&gt;3.0%
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;of the original loan amount at time of maturity.
Therefore, these amounts totaling $&lt;span id="xdx_907_eus-gaap--AmortizationOfFinancingCosts_pp0p0_c20210601__20210618__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_zfrGpoPgCuj4"&gt;300,000
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;were being amortized as interest expense using
the effective interest method over the life of the loan. During the three and six-month periods ended June 30, 2021, the Company incurred
$&lt;span id="xdx_90C_eus-gaap--InterestExpenseDebt_c20210101__20210630__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_pp0p0"&gt;7,042
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;in interest expense and amortized $&lt;span id="xdx_906_eus-gaap--AmortizationOfFinancingCostsAndDiscounts_pp0p0_c20210101__20210630__us-gaap--TypeOfArrangementAxis__custom--SVBLoanFacilityMember_zCD8P5Rm7fWd"&gt;6,457
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;as interest expense for debt discounts and end-of-term
fee in connection with the SVB Financing Facility.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p id="xdx_89B_eus-gaap--ScheduleOfMaturitiesOfLongTermDebtTableTextBlock_zA0OrhEcHcg5" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Following
is a schedule of future principal payments, net of unamortized debt discounts and amortized end-of-term fee, due on the SVB Loan
Facility:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8B9_z1LBw1ybetAj" style="display: none"&gt;Schedule
of Future Principle Payments, Net of Unamortized Debt Discounts&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; margin-left: auto; border-collapse: collapse; width: 80%; margin-right: auto"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_49B_20210630_zRN0y04DfbZ2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;As
    of June 30,&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_406_eus-gaap--LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths_iI_pp0p0_maDICAzd4S_zGpQzPb0URLc" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2022&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0998"&gt;&#x2013;&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_401_eus-gaap--LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo_iI_pp0p0_maDICAzd4S_z9GgFD7BPiOi" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2023&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1000"&gt;&#x2013;&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_408_eus-gaap--LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree_iI_pp0p0_maDICAzd4S_zpMClawZJ8k4" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 80%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2024&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;3,000,000&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_408_ecustom--LongTermDebtMaturitiesRepaymentsOfPrincipalYearFourAndThereAfter_iI_pp0p0_maDICAzd4S_z7o7oasIwqk7" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2025 and&lt;/span&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;
    thereafter&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;3,000,000&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_409_eus-gaap--DebtInstrumentCarryingAmount_iTI_pp0p0_mtDICAzd4S_maLTDzrgw_zqnRyTti7kw9" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Subtotal of future principal payments&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;6,000,000&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_400_eus-gaap--DeferredFinanceCostsNet_iNI_pp0p0_di_msLTDzrgw_zccsqLc8FVH" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Unamortized debt premium,
    net&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;(236,913&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;)&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_401_eus-gaap--LongTermDebt_iTI_pp0p0_mtLTDzrgw_zXoiqTV25pye" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-left: 10pt; text-align: left; padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Total&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;5,763,087&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p id="xdx_8A9_zy9OfBhf7rOi" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;i&gt;Horizon
Credit Agreement&lt;/i&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
June 27, 2018, the Company entered into a loan agreement with Horizon Technology Finance Corporation (&#x201c;Horizon&#x201d;) that provided
$&lt;span id="xdx_903_eus-gaap--LineOfCreditFacilityMaximumBorrowingCapacity_iI_pn6n6_c20180627__us-gaap--TypeOfArrangementAxis__custom--InitialHorizonCreditAgreementMember_zkfQB5GOdQAc"&gt;10
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million in new capital (the &#x201c;Horizon Credit
Agreement&#x201d;). The Company drew down $&lt;span id="xdx_904_eus-gaap--ProceedsFromLinesOfCredit_pn6n6_c20180626__20180627__us-gaap--TypeOfArrangementAxis__custom--InitialHorizonCreditAgreementMember_z966F2N1lnT6"&gt;10
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million upon closing of the Horizon Credit Agreement
on June 27, 2018. On August 28, 2020, Horizon and the Company amended the Horizon Credit Agreement (the &#x201c;Amendment&#x201d;) whereby
Celsion repaid $&lt;span id="xdx_90E_eus-gaap--RepaymentsOfNotesPayable_pn6n6_c20200827__20200828__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_zuJUbukFi259"&gt;5
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million of the $10 million loan and $&lt;span id="xdx_905_ecustom--PaymentOfDebtEndTermCharges_pn5n6_c20200827__20200828__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_z7jYmIYCWGV1"&gt;0.2
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million in related end of term charges, and the
remaining $&lt;span id="xdx_90C_eus-gaap--LineOfCreditFacilityRemainingBorrowingCapacity_iI_pn6n6_c20180627__us-gaap--TypeOfArrangementAxis__custom--InitialHorizonCreditAgreementMember_zlsIXpBRHX2d"&gt;5
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million in obligations were restructured as set
forth below.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Pursuant
to the Amendment, the remaining $&lt;span id="xdx_908_eus-gaap--DebtInstrumentFaceAmount_iI_pn6n6_c20200828__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_zce3TW5sOzha"&gt;5
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million in obligations of Celsion under the Horizon
Credit Agreement was secured by a first-priority security interest in substantially all assets of Celsion other than intellectual
property assets. &lt;span id="xdx_90A_eus-gaap--DebtInstrumentInterestRateTerms_c20200827__20200828__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_zH8QZJ3kIg7g"&gt;The
obligations bore interest at a rate calculated based an amount by which the one-month LIBOR exceeds 2% plus 7.625%. In no event
shall the interest rate be less than 9.625%. Payments pursuant to the Amendment were interest only for the first twelve (12) months
after August 1, 2020, followed by a 21-month amortization period of principal and interest through the scheduled maturity date on April
1, 2023. In addition, the remaining $5 million in obligations was subject to an end of term fee equal, in the aggregate, to $&lt;/span&gt;&lt;/span&gt;&lt;span id="xdx_902_eus-gaap--DebtInstrumentFeeAmount_c20200828__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_pp0p0" style="font: 10pt Times New Roman, Times, Serif"&gt;275,000&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;,
which amount was payable upon the maturity of the obligations or upon the date of final payment or default, as applicable. &lt;span id="xdx_90C_eus-gaap--DebtInstrumentRestrictiveCovenants_c20200827__20200828__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember"&gt;In
connection with the Amendment, Celsion agreed to a liquidity covenant which provides that, at all times, Celsion shall maintain unrestricted
cash and/or cash equivalents on deposit in accounts over which the applicable Lenders maintain an account control agreement in an amount
not less than $2.5 million. In addition, pursuant to the Amendment, Celsion agreed to provide evidence to Horizon on or before March
31, 2021, that it received aggregate cash proceeds of not less than $5 million from the sale of equity, debt, its New Jersey net operating
losses, or a combination thereof, subsequent to the date of the Amendment.&lt;/span&gt;&lt;/span&gt; &lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
Company met this requirement during the fourth quarter of 2020.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;In
connection with the Horizon Credit Agreement, the Company incurred financing fees and expenses totaling $&lt;span id="xdx_90C_eus-gaap--InterestAndDebtExpense_c20180626__20180627__us-gaap--TypeOfArrangementAxis__custom--InitialHorizonCreditAgreementMember_pp0p0"&gt;175,000
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;which were recorded and classified as debt discount.
In addition, the Company paid loan origination fees of $&lt;span id="xdx_90F_eus-gaap--LoanProcessingFee_c20180626__20180627__us-gaap--TypeOfArrangementAxis__custom--InitialHorizonCreditAgreementMember_pp0p0"&gt;100,000
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;which were recorded and classified as debt discount.
These debt discount amounts totaling $&lt;span id="xdx_90D_eus-gaap--DebtInstrumentUnamortizedDiscount_c20180627__us-gaap--TypeOfArrangementAxis__custom--InitialHorizonCreditAgreementMember_pp0p0"&gt;782,116
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;were being amortized as interest expense using
the effective interest method over the life of the loan. Also, in connection with each of the Horizon Credit Agreement, the Company was
required to pay an end of term charge equal to &lt;span id="xdx_905_ecustom--EndOfTermChargePercentage_c20180626__20180627__us-gaap--TypeOfArrangementAxis__custom--InitialHorizonCreditAgreementMember_pdd"&gt;4.0%
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;of the original loan amount at time of maturity.
Therefore, those amounts totaling $&lt;span id="xdx_909_eus-gaap--DeferredFinanceCostsNet_c20180627__us-gaap--TypeOfArrangementAxis__custom--InitialHorizonCreditAgreementMember_pp0p0"&gt;400,000
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;were being amortized as interest expense using
the effective interest method over the life of the loan.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;




&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;As
a fee in connection with the Horizon Credit Agreement, Celsion issued Horizon warrants exercisable for a total of &lt;span id="xdx_904_eus-gaap--ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_c20180627__us-gaap--TypeOfArrangementAxis__custom--InitialHorizonCreditAgreementMember__us-gaap--StatementEquityComponentsAxis__us-gaap--CommonStockMember_pdd"&gt;190,114
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;shares of Celsion&#x2019;s common stock (the &#x201c;Existing
Warrants&#x201d;) at a per share exercise price of $&lt;span id="xdx_907_eus-gaap--ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_c20180627__us-gaap--TypeOfArrangementAxis__custom--InitialHorizonCreditAgreementMember__us-gaap--StatementEquityComponentsAxis__us-gaap--CommonStockMember_pdd"&gt;2.63&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;.
The Horizon Warrants were immediately exercisable for cash or by net exercise from the date of grant and will expire after ten years
from the date of grant. The Company valued the Horizon Warrants issued using the Black-Scholes option pricing model and recorded a total
of $&lt;span id="xdx_90B_eus-gaap--FairValueAdjustmentOfWarrants_c20180626__20180627__us-gaap--TypeOfArrangementAxis__custom--InitialHorizonCreditAgreementMember_pp0p0"&gt;507,116
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;as a direct deduction from the debt liability,
consistent with the presentation of debt discounts, and are being amortized as interest expense using the effective interest method over
the life of the loan. Pursuant to the Amendment, one-half of the aggregate Existing Warrants, exercisable for a total of &lt;span id="xdx_903_ecustom--ClassOfWarrantOrRightWarrantsOrRightsCancelled_c20200828__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember__us-gaap--StatementEquityComponentsAxis__us-gaap--CommonStockMember_pdd"&gt;95,057
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;shares of Celsion&#x2019;s common stock, have
been canceled, and, in connection with the Amendment, Celsion issued Horizon new warrants exercisable at a per share exercise price equal
to $&lt;span id="xdx_906_eus-gaap--ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_c20200828__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember__us-gaap--StatementEquityComponentsAxis__us-gaap--CommonStockMember_pdd"&gt;1.01
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;for a total of &lt;span id="xdx_904_eus-gaap--ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_c20200828__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember__us-gaap--StatementEquityComponentsAxis__us-gaap--CommonStockMember_pdd"&gt;247,525
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;shares of Celsion&#x2019;s common stock (the &#x201c;New
Warrants&#x201d; and, together with the Existing Warrants, the &#x201c;Warrants&#x201d;). The remaining &lt;span id="xdx_904_eus-gaap--ClassOfWarrantOrRightOutstanding_c20180627__us-gaap--TypeOfArrangementAxis__custom--InitialHorizonCreditAgreementMember__us-gaap--StatementEquityComponentsAxis__us-gaap--CommonStockMember_pdd"&gt;95,057
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Existing Warrants issued in connection with the
Horizon Credit Agreement remain outstanding at a per share exercise price of $2.63.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
New Warrants were immediately exercisable for cash or by net exercise from the date of grant and will expire after ten years from
the date of grant. Effective October 27, 2020. The Horizon Credit Agreement contains customary representations, warranties and affirmative
and negative covenants including, among other things, covenants that limit or restrict Celsion&#x2019;s ability to grant liens, incur
indebtedness, make certain restricted payments, merge, or consolidate and make dispositions of assets.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
Amendment was evaluated in accordance with FASB ASC 470-50, &lt;i&gt;Debt-Modifications and Extinguishments&lt;/i&gt;, for debt modification and
extinguishment accounting. We accounted for the $&lt;span id="xdx_904_eus-gaap--PaymentsOfDebtExtinguishmentCosts_pn6n6_c20200827__20200828__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_zAUWcpet6Cdl"&gt;5
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million we repaid as a debt extinguishment thereby
reducing the principal obligations accordingly. Also, in connection with the $5 million repayment, we recognized as interest expense,
approximately $&lt;span id="xdx_909_eus-gaap--DebtInstrumentUnamortizedDiscount_iI_pn5n6_c20200828__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_zUp1qgaGEWKk"&gt;0.2
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million of unamortized debt discount, deferred
financing and end of term fees related to the repaid obligation in August 2020.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;We
accounted for the remaining $5 million of obligation under the Amendment as a debt modification to the initial agreement with respect
to the minor changes in cash flows. Also, in connection with the $5 million remaining obligations, we recorded $&lt;span id="xdx_905_eus-gaap--DeferredFinanceCostsNet_c20200828__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_pp0p0"&gt;5,000
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;of financing fees and the New Warrant fair value
of $&lt;span id="xdx_90B_eus-gaap--WarrantsNotSettleableInCashFairValueDisclosure_c20200828__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_pp0p0"&gt;247,548
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;as additional debt discount on the $5 million
remaining obligation. Therefore, approximately $&lt;span id="xdx_902_eus-gaap--DebtInstrumentUnamortizedDiscount_c20210630__us-gaap--TypeOfArrangementAxis__custom--AmendmentToHorizonCreditAgreementMember__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_pp0p0"&gt;109,706
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;of unamortized debt discount will be amortized
over the remaining life of the new obligations. The $&lt;span id="xdx_903_ecustom--EndOfTermFees_c20180626__20180627__us-gaap--TypeOfArrangementAxis__custom--InitialHorizonCreditAgreementMember_pp0p0"&gt;275,000
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;of end of term fees, net of previously amortized
end of term fees totaling $&lt;span id="xdx_908_eus-gaap--DebtInstrumentFeeAmount_c20180627__us-gaap--TypeOfArrangementAxis__custom--InitialHorizonCreditAgreementMember_pp0p0"&gt;142,605
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;previously accrued on the original note associated
with the $5 million remaining obligation, will be amortized as interest expense over the remaining life of the new obligations.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;During
the three and six-month periods ended June 30, 2021, the Company incurred $&lt;span id="xdx_905_eus-gaap--InterestExpenseDebt_pp0p0_c20210401__20210630__us-gaap--DebtInstrumentAxis__custom--InitialHorizonCreditAgreementAmendmentMember_zz3mrabrYijj"&gt;105,607
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;and $&lt;span id="xdx_906_eus-gaap--InterestExpenseDebt_pp0p0_c20210101__20210630__us-gaap--DebtInstrumentAxis__custom--InitialHorizonCreditAgreementAmendmentMember_zoXmKKqJxf3"&gt;225,920&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;,
respectively, in interest expense and amortized $&lt;span id="xdx_908_eus-gaap--AmortizationOfFinancingCosts_pp0p0_c20210401__20210630__us-gaap--DebtInstrumentAxis__custom--InitialHorizonCreditAgreementAmendmentMember_zx6z5ZvsQLYf"&gt;102,126
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;and $&lt;span id="xdx_906_eus-gaap--AmortizationOfFinancingCosts_c20210101__20210630__us-gaap--DebtInstrumentAxis__custom--InitialHorizonCreditAgreementAmendmentMember_pp0p0"&gt;139,428
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;as interest expense for debt discounts and end
of term charges in connection with the Horizon Credit Agreement. During the three and six-month periods ended June 30, 2020, the Company
incurred $&lt;span id="xdx_907_eus-gaap--InterestExpenseDebt_pp0p0_c20200401__20200630__us-gaap--DebtInstrumentAxis__custom--InitialHorizonCreditAgreementAmendmentMember_z8a6wbHwmch1"&gt;243,299
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;and $&lt;span id="xdx_90C_eus-gaap--InterestExpenseDebt_c20200101__20200630__us-gaap--DebtInstrumentAxis__custom--InitialHorizonCreditAgreementAmendmentMember_pp0p0"&gt;486,597&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;,
respectively, in interest expense and amortized $&lt;span id="xdx_906_eus-gaap--AmortizationOfFinancingCosts_pp0p0_c20200401__20200630__us-gaap--DebtInstrumentAxis__custom--InitialHorizonCreditAgreementAmendmentMember_zXVN04mODJ1i"&gt;96,727
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;and $&lt;span id="xdx_904_eus-gaap--AmortizationOfFinancingCosts_c20200101__20200630__us-gaap--DebtInstrumentAxis__custom--InitialHorizonCreditAgreementAmendmentMember_pp0p0"&gt;192,793&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;,
respectfully, as interest expense for debt discounts and end of term charges in connection with the Horizon Credit Agreement.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p id="xdx_899_eus-gaap--ScheduleOfDebtTableTextBlock_zxTOtvYAFLbl" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
June 18, 2021, as a condition of entering into the SVB Loan Facility, the Company paid the outstanding principal balance,
an early termination fee and the end of term charges in full satisfaction of the Horizon Credit Agreement, as amended.
Following is a schedule of the amounts paid to Horizon on June 18, 2021.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8BB_zkVw8gEY8R8b" style="display: none"&gt;Schedule
of Debt&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; margin-left: auto; border-collapse: collapse; width: 80%; margin-right: auto"&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 80%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Principal balance at June 18, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98A_eus-gaap--LineOfCredit_iS_pp0p0_c20210619__20210630__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_zAmYhkUZFuhk" style="width: 16%; text-align: right" title="Line of credit, beginning balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;5,000,000&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Early termination fees&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_985_ecustom--EarlyTerminationFees_c20210619__20210630__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_zgVnQaVJ4SS5" style="text-align: right" title="Early termination fees"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;150,000&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;End of term charges&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98D_ecustom--EndOfTermFees_pp0p0_c20210619__20210630__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_zMGjpuyzQG2i" style="border-bottom: Black 1.5pt solid; text-align: right" title="End of term charges"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;275,000&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="padding-left: 10pt; padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Total&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_986_eus-gaap--LineOfCredit_iE_pp0p0_c20210619__20210630__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_zD1y3El5W0k4" style="border-bottom: Black 2.5pt double; text-align: right" title="Line of credit, ending balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;5,425,000&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p id="xdx_8AC_zWYHsRZk7bzd" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;During
the three and six months ended June 30, 2021, the Company recorded a loss of $&lt;span id="xdx_907_eus-gaap--GainLossOnContractTermination_c20210101__20210630__us-gaap--TypeOfArrangementAxis__custom--HorizonCreditAgreementMember_pp0p0"&gt;234,419
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;on the termination of the Horizon Credit Agreement,
as amended, which represented the early termination fee and the end of term fees, net of previously amortized interest expense totaling
$&lt;span id="xdx_90A_eus-gaap--InterestExpenseDebt_c20210101__20210630__us-gaap--TypeOfArrangementAxis__custom--HorizonCreditAgreementMember_pp0p0"&gt;190,581
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;on the date of its payoff.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

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    <us-gaap:LineOfCreditFacilityMaximumBorrowingCapacity
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      decimals="-6"
      unitRef="USD">10000000</us-gaap:LineOfCreditFacilityMaximumBorrowingCapacity>
    <us-gaap:ProceedsFromLinesOfCredit
      contextRef="From2021-06-012021-06-18_custom_SVBLoanFacilityMember"
      decimals="-6"
      unitRef="USD">6000000</us-gaap:ProceedsFromLinesOfCredit>
    <us-gaap:RestrictedCash
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      unitRef="USD">6000000.0</us-gaap:RestrictedCash>
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      decimals="INF"
      unitRef="Percentage">0.0325</us-gaap:DebtInstrumentInterestRateStatedPercentage>
    <CLSN:FinalPaymentPercentage
      contextRef="AsOf2021-06-18_custom_SVBLoanFacilityMember"
      decimals="INF"
      unitRef="Percentage">0.03</CLSN:FinalPaymentPercentage>
    <us-gaap:LineOfCredit
      contextRef="AsOf2021-06-18_custom_SVBLoanFacilityMember"
      decimals="-6"
      unitRef="USD">10000000</us-gaap:LineOfCredit>
    <us-gaap:LineOfCreditFacilityCommitmentFeeAmount
      contextRef="From2021-06-012021-06-18_custom_SVBLoanFacilityMember"
      decimals="0"
      unitRef="USD">0</us-gaap:LineOfCreditFacilityCommitmentFeeAmount>
    <us-gaap:DebtConversionConvertedInstrumentWarrantsOrOptionsIssued1
      contextRef="From2021-06-012021-06-18_custom_SVBLoanFacilityMember"
      decimals="INF"
      unitRef="Shares">0</us-gaap:DebtConversionConvertedInstrumentWarrantsOrOptionsIssued1>
    <us-gaap:DebtInstrumentDescription contextRef="From2021-06-012021-06-18_custom_SVBLoanFacilityMember">Payments
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    <us-gaap:InterestAndDebtExpense
      contextRef="From2021-06-012021-06-18_custom_SVBLoanFacilityMember"
      decimals="0"
      unitRef="USD">243370</us-gaap:InterestAndDebtExpense>
    <CLSN:EndOfTermChargePercentage
      contextRef="From2021-06-012021-06-18_custom_SVBLoanFacilityMember"
      decimals="INF"
      unitRef="Percentage">0.030</CLSN:EndOfTermChargePercentage>
    <us-gaap:AmortizationOfFinancingCosts
      contextRef="From2021-06-012021-06-18_custom_SVBLoanFacilityMember"
      decimals="0"
      unitRef="USD">300000</us-gaap:AmortizationOfFinancingCosts>
    <us-gaap:InterestExpenseDebt
      contextRef="From2021-01-012021-06-30_custom_SVBLoanFacilityMember"
      decimals="0"
      unitRef="USD">7042</us-gaap:InterestExpenseDebt>
    <us-gaap:AmortizationOfFinancingCostsAndDiscounts
      contextRef="From2021-01-012021-06-30_custom_SVBLoanFacilityMember"
      decimals="0"
      unitRef="USD">6457</us-gaap:AmortizationOfFinancingCostsAndDiscounts>
    <us-gaap:ScheduleOfMaturitiesOfLongTermDebtTableTextBlock contextRef="From2021-01-01to2021-06-30">&lt;p id="xdx_89B_eus-gaap--ScheduleOfMaturitiesOfLongTermDebtTableTextBlock_zA0OrhEcHcg5" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Following
is a schedule of future principal payments, net of unamortized debt discounts and amortized end-of-term fee, due on the SVB Loan
Facility:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8B9_z1LBw1ybetAj" style="display: none"&gt;Schedule
of Future Principle Payments, Net of Unamortized Debt Discounts&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; margin-left: auto; border-collapse: collapse; width: 80%; margin-right: auto"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_49B_20210630_zRN0y04DfbZ2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;As
    of June 30,&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_406_eus-gaap--LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths_iI_pp0p0_maDICAzd4S_zGpQzPb0URLc" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2022&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl0998"&gt;&#x2013;&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_401_eus-gaap--LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo_iI_pp0p0_maDICAzd4S_z9GgFD7BPiOi" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2023&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1000"&gt;&#x2013;&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_408_eus-gaap--LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree_iI_pp0p0_maDICAzd4S_zpMClawZJ8k4" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 80%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2024&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;3,000,000&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_408_ecustom--LongTermDebtMaturitiesRepaymentsOfPrincipalYearFourAndThereAfter_iI_pp0p0_maDICAzd4S_z7o7oasIwqk7" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2025 and&lt;/span&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;
    thereafter&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;3,000,000&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_409_eus-gaap--DebtInstrumentCarryingAmount_iTI_pp0p0_mtDICAzd4S_maLTDzrgw_zqnRyTti7kw9" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Subtotal of future principal payments&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;6,000,000&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_400_eus-gaap--DeferredFinanceCostsNet_iNI_pp0p0_di_msLTDzrgw_zccsqLc8FVH" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Unamortized debt premium,
    net&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;(236,913&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;)&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_401_eus-gaap--LongTermDebt_iTI_pp0p0_mtLTDzrgw_zXoiqTV25pye" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-left: 10pt; text-align: left; padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Total&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;5,763,087&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

</us-gaap:ScheduleOfMaturitiesOfLongTermDebtTableTextBlock>
    <us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">3000000</us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree>
    <CLSN:LongTermDebtMaturitiesRepaymentsOfPrincipalYearFourAndThereAfter contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">3000000</CLSN:LongTermDebtMaturitiesRepaymentsOfPrincipalYearFourAndThereAfter>
    <us-gaap:DebtInstrumentCarryingAmount contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">6000000</us-gaap:DebtInstrumentCarryingAmount>
    <us-gaap:DeferredFinanceCostsNet contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">236913</us-gaap:DeferredFinanceCostsNet>
    <us-gaap:LongTermDebt contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">5763087</us-gaap:LongTermDebt>
    <us-gaap:LineOfCreditFacilityMaximumBorrowingCapacity
      contextRef="AsOf2018-06-27_custom_InitialHorizonCreditAgreementMember"
      decimals="-6"
      unitRef="USD">10000000</us-gaap:LineOfCreditFacilityMaximumBorrowingCapacity>
    <us-gaap:ProceedsFromLinesOfCredit
      contextRef="From2018-06-262018-06-27_custom_InitialHorizonCreditAgreementMember"
      decimals="-6"
      unitRef="USD">10000000</us-gaap:ProceedsFromLinesOfCredit>
    <us-gaap:RepaymentsOfNotesPayable
      contextRef="From2020-08-272020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember"
      decimals="-6"
      unitRef="USD">5000000</us-gaap:RepaymentsOfNotesPayable>
    <CLSN:PaymentOfDebtEndTermCharges
      contextRef="From2020-08-272020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember"
      decimals="-5"
      unitRef="USD">200000</CLSN:PaymentOfDebtEndTermCharges>
    <us-gaap:LineOfCreditFacilityRemainingBorrowingCapacity
      contextRef="AsOf2018-06-27_custom_InitialHorizonCreditAgreementMember"
      decimals="-6"
      unitRef="USD">5000000</us-gaap:LineOfCreditFacilityRemainingBorrowingCapacity>
    <us-gaap:DebtInstrumentFaceAmount
      contextRef="AsOf2020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember"
      decimals="-6"
      unitRef="USD">5000000</us-gaap:DebtInstrumentFaceAmount>
    <us-gaap:DebtInstrumentInterestRateTerms contextRef="From2020-08-272020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember">The
obligations bore interest at a rate calculated based an amount by which the one-month LIBOR exceeds 2% plus 7.625%. In no event
shall the interest rate be less than 9.625%. Payments pursuant to the Amendment were interest only for the first twelve (12) months
after August 1, 2020, followed by a 21-month amortization period of principal and interest through the scheduled maturity date on April
1, 2023. In addition, the remaining $5 million in obligations was subject to an end of term fee equal, in the aggregate, to $</us-gaap:DebtInstrumentInterestRateTerms>
    <us-gaap:DebtInstrumentFeeAmount
      contextRef="AsOf2020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember"
      decimals="0"
      unitRef="USD">275000</us-gaap:DebtInstrumentFeeAmount>
    <us-gaap:DebtInstrumentRestrictiveCovenants contextRef="From2020-08-272020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember">In
connection with the Amendment, Celsion agreed to a liquidity covenant which provides that, at all times, Celsion shall maintain unrestricted
cash and/or cash equivalents on deposit in accounts over which the applicable Lenders maintain an account control agreement in an amount
not less than $2.5 million. In addition, pursuant to the Amendment, Celsion agreed to provide evidence to Horizon on or before March
31, 2021, that it received aggregate cash proceeds of not less than $5 million from the sale of equity, debt, its New Jersey net operating
losses, or a combination thereof, subsequent to the date of the Amendment.</us-gaap:DebtInstrumentRestrictiveCovenants>
    <us-gaap:InterestAndDebtExpense
      contextRef="From2018-06-262018-06-27_custom_InitialHorizonCreditAgreementMember"
      decimals="0"
      unitRef="USD">175000</us-gaap:InterestAndDebtExpense>
    <us-gaap:LoanProcessingFee
      contextRef="From2018-06-262018-06-27_custom_InitialHorizonCreditAgreementMember"
      decimals="0"
      unitRef="USD">100000</us-gaap:LoanProcessingFee>
    <us-gaap:DebtInstrumentUnamortizedDiscount
      contextRef="AsOf2018-06-27_custom_InitialHorizonCreditAgreementMember"
      decimals="0"
      unitRef="USD">782116</us-gaap:DebtInstrumentUnamortizedDiscount>
    <CLSN:EndOfTermChargePercentage
      contextRef="From2018-06-262018-06-27_custom_InitialHorizonCreditAgreementMember"
      decimals="INF"
      unitRef="Percentage">0.040</CLSN:EndOfTermChargePercentage>
    <us-gaap:DeferredFinanceCostsNet
      contextRef="AsOf2018-06-27_custom_InitialHorizonCreditAgreementMember"
      decimals="0"
      unitRef="USD">400000</us-gaap:DeferredFinanceCostsNet>
    <us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights
      contextRef="AsOf2018-06-27_custom_InitialHorizonCreditAgreementMember_us-gaap_CommonStockMember"
      decimals="INF"
      unitRef="Shares">190114</us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights>
    <us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1
      contextRef="AsOf2018-06-27_custom_InitialHorizonCreditAgreementMember_us-gaap_CommonStockMember"
      decimals="INF"
      unitRef="USDPShares">2.63</us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1>
    <us-gaap:FairValueAdjustmentOfWarrants
      contextRef="From2018-06-262018-06-27_custom_InitialHorizonCreditAgreementMember"
      decimals="0"
      unitRef="USD">507116</us-gaap:FairValueAdjustmentOfWarrants>
    <CLSN:ClassOfWarrantOrRightWarrantsOrRightsCancelled
      contextRef="AsOf2020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember_us-gaap_CommonStockMember"
      decimals="INF"
      unitRef="Shares">95057</CLSN:ClassOfWarrantOrRightWarrantsOrRightsCancelled>
    <us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1
      contextRef="AsOf2020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember_us-gaap_CommonStockMember"
      decimals="INF"
      unitRef="USDPShares">1.01</us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1>
    <us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights
      contextRef="AsOf2020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember_us-gaap_CommonStockMember"
      decimals="INF"
      unitRef="Shares">247525</us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights>
    <us-gaap:ClassOfWarrantOrRightOutstanding
      contextRef="AsOf2018-06-27_custom_InitialHorizonCreditAgreementMember_us-gaap_CommonStockMember"
      decimals="INF"
      unitRef="Shares">95057</us-gaap:ClassOfWarrantOrRightOutstanding>
    <us-gaap:PaymentsOfDebtExtinguishmentCosts
      contextRef="From2020-08-272020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember"
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      unitRef="USD">5000000</us-gaap:PaymentsOfDebtExtinguishmentCosts>
    <us-gaap:DebtInstrumentUnamortizedDiscount
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      decimals="-5"
      unitRef="USD">200000</us-gaap:DebtInstrumentUnamortizedDiscount>
    <us-gaap:DeferredFinanceCostsNet
      contextRef="AsOf2020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember"
      decimals="0"
      unitRef="USD">5000</us-gaap:DeferredFinanceCostsNet>
    <us-gaap:WarrantsNotSettleableInCashFairValueDisclosure
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      unitRef="USD">247548</us-gaap:WarrantsNotSettleableInCashFairValueDisclosure>
    <us-gaap:DebtInstrumentUnamortizedDiscount
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      unitRef="USD">109706</us-gaap:DebtInstrumentUnamortizedDiscount>
    <CLSN:EndOfTermFees
      contextRef="From2018-06-262018-06-27_custom_InitialHorizonCreditAgreementMember"
      decimals="0"
      unitRef="USD">275000</CLSN:EndOfTermFees>
    <us-gaap:DebtInstrumentFeeAmount
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      decimals="0"
      unitRef="USD">142605</us-gaap:DebtInstrumentFeeAmount>
    <us-gaap:InterestExpenseDebt
      contextRef="From2021-04-012021-06-30_custom_InitialHorizonCreditAgreementAmendmentMember"
      decimals="0"
      unitRef="USD">105607</us-gaap:InterestExpenseDebt>
    <us-gaap:InterestExpenseDebt
      contextRef="From2021-01-012021-06-30_custom_InitialHorizonCreditAgreementAmendmentMember"
      decimals="0"
      unitRef="USD">225920</us-gaap:InterestExpenseDebt>
    <us-gaap:AmortizationOfFinancingCosts
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      decimals="0"
      unitRef="USD">102126</us-gaap:AmortizationOfFinancingCosts>
    <us-gaap:AmortizationOfFinancingCosts
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      decimals="0"
      unitRef="USD">139428</us-gaap:AmortizationOfFinancingCosts>
    <us-gaap:InterestExpenseDebt
      contextRef="From2020-04-012020-06-30_custom_InitialHorizonCreditAgreementAmendmentMember"
      decimals="0"
      unitRef="USD">243299</us-gaap:InterestExpenseDebt>
    <us-gaap:InterestExpenseDebt
      contextRef="From2020-01-012020-06-30_custom_InitialHorizonCreditAgreementAmendmentMember"
      decimals="0"
      unitRef="USD">486597</us-gaap:InterestExpenseDebt>
    <us-gaap:AmortizationOfFinancingCosts
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      decimals="0"
      unitRef="USD">96727</us-gaap:AmortizationOfFinancingCosts>
    <us-gaap:AmortizationOfFinancingCosts
      contextRef="From2020-01-012020-06-30_custom_InitialHorizonCreditAgreementAmendmentMember"
      decimals="0"
      unitRef="USD">192793</us-gaap:AmortizationOfFinancingCosts>
    <us-gaap:ScheduleOfDebtTableTextBlock contextRef="From2021-01-01to2021-06-30">&lt;p id="xdx_899_eus-gaap--ScheduleOfDebtTableTextBlock_zxTOtvYAFLbl" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
June 18, 2021, as a condition of entering into the SVB Loan Facility, the Company paid the outstanding principal balance,
an early termination fee and the end of term charges in full satisfaction of the Horizon Credit Agreement, as amended.
Following is a schedule of the amounts paid to Horizon on June 18, 2021.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8BB_zkVw8gEY8R8b" style="display: none"&gt;Schedule
of Debt&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; margin-left: auto; border-collapse: collapse; width: 80%; margin-right: auto"&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 80%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Principal balance at June 18, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98A_eus-gaap--LineOfCredit_iS_pp0p0_c20210619__20210630__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_zAmYhkUZFuhk" style="width: 16%; text-align: right" title="Line of credit, beginning balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;5,000,000&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Early termination fees&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_985_ecustom--EarlyTerminationFees_c20210619__20210630__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_zgVnQaVJ4SS5" style="text-align: right" title="Early termination fees"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;150,000&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;End of term charges&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98D_ecustom--EndOfTermFees_pp0p0_c20210619__20210630__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_zMGjpuyzQG2i" style="border-bottom: Black 1.5pt solid; text-align: right" title="End of term charges"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;275,000&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="padding-left: 10pt; padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Total&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_986_eus-gaap--LineOfCredit_iE_pp0p0_c20210619__20210630__dei--LegalEntityAxis__custom--HorizonTechnologyFinanceCorporationMember_zD1y3El5W0k4" style="border-bottom: Black 2.5pt double; text-align: right" title="Line of credit, ending balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;5,425,000&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

</us-gaap:ScheduleOfDebtTableTextBlock>
    <us-gaap:LineOfCredit
      contextRef="AsOf2021-06-18_custom_HorizonTechnologyFinanceCorporationMember"
      decimals="0"
      unitRef="USD">5000000</us-gaap:LineOfCredit>
    <CLSN:EarlyTerminationFees
      contextRef="From2021-06-192021-06-30_custom_HorizonTechnologyFinanceCorporationMember"
      decimals="0"
      unitRef="USD">150000</CLSN:EarlyTerminationFees>
    <CLSN:EndOfTermFees
      contextRef="From2021-06-192021-06-30_custom_HorizonTechnologyFinanceCorporationMember"
      decimals="0"
      unitRef="USD">275000</CLSN:EndOfTermFees>
    <us-gaap:LineOfCredit
      contextRef="AsOf2021-06-30_custom_HorizonTechnologyFinanceCorporationMember"
      decimals="0"
      unitRef="USD">5425000</us-gaap:LineOfCredit>
    <us-gaap:GainLossOnContractTermination
      contextRef="From2021-01-012021-06-30_custom_HorizonCreditAgreementMember"
      decimals="0"
      unitRef="USD">234419</us-gaap:GainLossOnContractTermination>
    <us-gaap:InterestExpenseDebt
      contextRef="From2021-01-012021-06-30_custom_HorizonCreditAgreementMember"
      decimals="0"
      unitRef="USD">190581</us-gaap:InterestExpenseDebt>
    <us-gaap:StockholdersEquityNoteDisclosureTextBlock contextRef="From2021-01-01to2021-06-30">&lt;p id="xdx_80B_eus-gaap--StockholdersEquityNoteDisclosureTextBlock_z4i556ELqwRh" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
12. &lt;span id="xdx_827_zwrisun1hGC8"&gt;Stockholders&#x2019; Equity&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;In
September 2018, the Company filed with the SEC a $&lt;span id="xdx_90F_ecustom--ShelfRegistrationStatementAmount_pn6n6_c20180901__20180930_z6kOyeRMUEy6"&gt;75
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million shelf registration statement on Form
S-3 (the 2018 Shelf Registration Statement) that allows the Company to issue any combination of common stock, preferred stock or warrants
to purchase common stock or preferred stock. This shelf registration was declared effective on October 12, 2018, and was
fully utilized by the end of January 2021.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;




&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
March 19, 2021, the Company filed with the SEC a new $&lt;span id="xdx_907_ecustom--ShelfRegistrationStatementAmount_pn6n6_c20210318__20210319_zBrO5S5vboV8"&gt;100
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million shelf registration statement on Form
S-3 (the &#x201c;2021 Registration Statement&#x201d;) that allows the Company to issue any combination of common stock, preferred stock
or warrants to purchase common stock or preferred stock. This shelf registration was declared effective on March 30, 2021.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;i&gt;&lt;span style="text-decoration: underline"&gt;Capital
on Demand&lt;sup&gt;TM&lt;/sup&gt; Sales Agreement&lt;/span&gt;&lt;/i&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
December 4, 2018, the Company entered into the Capital on Demand Agreement with JonesTrading, pursuant to which the Company may offer
and sell, from time to time, through JonesTrading shares of Common Stock having an aggregate offering price of up to $&lt;span id="xdx_905_ecustom--AggregateOfferingPrices_pn5n6_c20181202__20181204__us-gaap--TypeOfArrangementAxis__custom--CapitalOnDemandTMSalesAgreementMember_zjxEhECp5K63"&gt;16.0
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;During
2020 through June 30, 2020, the Company sold and issued an aggregate of &lt;span id="xdx_906_eus-gaap--StockIssuedDuringPeriodSharesNewIssues_pn5n6_c20200101__20200630__us-gaap--TypeOfArrangementAxis__custom--CapitalOnDemandAgreementMember_zSm2pkR5U73i"&gt;1.2
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million shares under the Capital on Demand
Agreement, receiving approximately $&lt;span id="xdx_900_eus-gaap--ProceedsFromIssuanceOfCommonStock_pn5n6_c20200101__20200630__us-gaap--TypeOfArrangementAxis__custom--CapitalOnDemandAgreementMember_zCADWbcV9O0h"&gt;3.5
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million in gross proceeds. During the first
half of 2021, the Company sold &lt;span id="xdx_906_eus-gaap--StockIssuedDuringPeriodSharesNewIssues_pn5n6_c20210101__20210331__us-gaap--TypeOfArrangementAxis__custom--CapitalOnDemandAgreementMember_zHPWaFmPEmU"&gt;7.2
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million shares under the Capital on Demand Agreement,
receiving approximately $&lt;span id="xdx_905_eus-gaap--ProceedsFromIssuanceOfCommonStock_pn5n6_c20210101__20210331__us-gaap--TypeOfArrangementAxis__custom--CapitalOnDemandAgreementMember_zXHcc671V5Pg"&gt;6.9
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million in gross proceeds under the Capital on
Demand Agreement.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;i&gt;&lt;span style="text-decoration: underline"&gt;Registered
Direct Offering&lt;/span&gt;&lt;/i&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
February 27, 2020, we entered into a Securities Purchase Agreement (the &#x201c;February 2020 Purchase Agreement&#x201d;) with several
institutional investors, pursuant to which we agreed to issue and sell, in a registered direct offering (the &#x201c;February 2020
Offering&#x201d;), an aggregate of &lt;span id="xdx_90F_eus-gaap--StockIssuedDuringPeriodSharesNewIssues_pid_c20200226__20200227__us-gaap--TypeOfArrangementAxis__custom--SecuritiesPurchaseAgreementMember_zUAhIVI0k3lb"&gt;4,571,428 &lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;shares
of our common stock at an offering price of $&lt;span id="xdx_90A_eus-gaap--SharesIssuedPricePerShare_iI_pid_c20200227__us-gaap--TypeOfArrangementAxis__custom--SecuritiesPurchaseAgreementMember_zQxwlSRowZd2"&gt;1.05 &lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;per
Share for gross proceeds of approximately $&lt;span id="xdx_905_eus-gaap--ProceedsFromIssuanceOfCommonStock_pn5n6_c20200226__20200227__us-gaap--TypeOfArrangementAxis__custom--SecuritiesPurchaseAgreementMember_zoT3KNK5lUu5"&gt;4.8 &lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million
before the deduction of the Placement Agent fees and offering expenses. In a concurrent private placement (the &#x201c;Private
Placement&#x201d;), the Company issued to the investors that participated in the February 2020 Offering, for no additional
consideration, warrants to purchase up to &lt;span id="xdx_90C_eus-gaap--ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight_c20200227__us-gaap--TypeOfArrangementAxis__custom--SecuritiesPurchaseAgreementMember__us-gaap--StatementEquityComponentsAxis__custom--OriginalWarrantsMember_pdd"&gt;2,971,428 &lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;shares
of common stock (the &#x201c;Original Warrants&#x201d;). The Original Warrants were initially exercisable six months following their
date of issue and were set to expire on the &lt;span id="xdx_903_eus-gaap--WarrantsAndRightsOutstandingTerm_iI_dxL_c20200227__us-gaap--TypeOfArrangementAxis__custom--SecuritiesPurchaseAgreementMember__us-gaap--StatementEquityComponentsAxis__custom--OriginalWarrantsMember_zLhLDfQ92Fj" title="::XDX::P5Y"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1072"&gt;five-year&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;
anniversary of such initial exercise date. The Original Warrants had an exercise price of $&lt;span id="xdx_907_eus-gaap--ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_iI_pid_c20200227__us-gaap--TypeOfArrangementAxis__custom--SecuritiesPurchaseAgreementMember__us-gaap--StatementEquityComponentsAxis__custom--OriginalWarrantsMember_zzQ0oUkx6I1e"&gt;1.15 &lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;per
share subject to adjustment as provided therein. On March 12, 2020, the Company entered into private exchange agreements (the
&#x201c;Exchange Agreements&#x201d;) with holders of the Original Warrants. Pursuant to the Exchange Agreements, in return for a
higher exercise price of $&lt;span id="xdx_90D_eus-gaap--ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_iI_pid_c20200312__us-gaap--TypeOfArrangementAxis__custom--ExchangeAgreementsMember__us-gaap--StatementEquityComponentsAxis__us-gaap--WarrantMember_zmBGdzB62lid"&gt;1.24 &lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;per
share of common stock, the Company issued new warrants to the Investors to purchase up to &lt;span id="xdx_904_eus-gaap--ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight_iI_pid_c20200312__us-gaap--TypeOfArrangementAxis__custom--ExchangeAgreementsMember__us-gaap--StatementEquityComponentsAxis__us-gaap--WarrantMember_zDxruSt2GUpl"&gt;3,200,000 &lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;shares
of common stock (the &#x201c;Exchange Warrants&#x201d;) in exchange for the Original Warrants. The Exchange Warrants, like the
Original Warrants, are initially exercisable six months following their issuance (the &#x201c;Initial Exercise Date&#x201d;) and
expire on the &lt;span id="xdx_90A_eus-gaap--WarrantsAndRightsOutstandingTerm_iI_dxL_c20200312__us-gaap--TypeOfArrangementAxis__custom--ExchangeAgreementsMember__us-gaap--StatementEquityComponentsAxis__us-gaap--WarrantMember_zvInSFBdHo4c" title="::XDX::P5Y"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1076"&gt;five-year&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;
anniversary of their Initial Exercise Date. Other than having a higher exercise price, different issue date, Initial Exercise Date
and expiration date, the terms of the Exchange Warrants are identical to those of the Original Warrants. On July 31, 2020, the
Company filed a Form S-3 Registration Statement to register the shares of common stock issuable under the Exchange Warrants; the
Registration Statement was declared effective by the SEC on August 13, 2020. No Exchange Warrants were exercised during 2020. During
2021 through the date of this Quarterly Report on Form 10-Q, the Company issued &lt;span id="xdx_90D_eus-gaap--ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight_iI_pn5n6_c20210630__us-gaap--TypeOfArrangementAxis__custom--ExchangeAgreementsMember_zfIt5TJCsBY6"&gt;1.2 &lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million
shares pursuant to investors exercising Exchange Warrants, receiving approximately $&lt;span id="xdx_90C_eus-gaap--ProceedsFromIssuanceOfWarrants_pn5n6_c20210101__20210630__us-gaap--TypeOfArrangementAxis__custom--ExchangeAgreementsMember_zTmpheC7YDWj"&gt;1.5 &lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million in
net proceeds.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;i&gt;&lt;span style="text-decoration: underline"&gt;Underwritten
Offering&lt;/span&gt;&lt;/i&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
June 22, 2020, the Company entered into an underwriting agreement (the &#x201c;Underwriting Agreement&#x201d;) with Oppenheimer &amp;amp; Co.
Inc. (the &#x201c;Underwriter&#x201d;), relating to the issuance and sale (the &#x201c;Underwritten Offering&#x201d;) of &lt;span id="xdx_90A_eus-gaap--StockIssuedDuringPeriodSharesNewIssues_c20200621__20200622__us-gaap--TypeOfArrangementAxis__custom--UnderwritingAgreementMember__us-gaap--SubsidiarySaleOfStockAxis__custom--UnderwrittenOfferingMember_zuYZrzK0hDlb"&gt;2,666,667
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;shares of the Company&#x2019;s common stock. Pursuant
to the terms of the Underwriting Agreement, the Underwriter agreed to purchase the shares at a price of $&lt;span id="xdx_903_eus-gaap--SharePrice_c20200622__us-gaap--TypeOfArrangementAxis__custom--UnderwritingAgreementMember__us-gaap--SubsidiarySaleOfStockAxis__custom--UnderwrittenOfferingMember_pdd"&gt;3.4875
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;per share. The Underwriter offered the shares
at a public offering price of $&lt;span id="xdx_907_eus-gaap--SharesIssuedPricePerShare_c20200622__us-gaap--TypeOfArrangementAxis__custom--UnderwritingAgreementMember__us-gaap--SubsidiarySaleOfStockAxis__custom--UnderwrittenOfferingMember_pdd"&gt;3.75
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;per share, reflecting an underwriting discount
equal to $&lt;span id="xdx_909_ecustom--UnderwritingDiscountPricePerShare_c20200621__20200622__us-gaap--TypeOfArrangementAxis__custom--UnderwritingAgreementMember__us-gaap--SubsidiarySaleOfStockAxis__custom--UnderwrittenOfferingMember_pdd"&gt;0.2625&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;,
or &lt;span id="xdx_90E_ecustom--PercentageOfUnderwritingDiscountOnPublicOfferingPrice_c20200621__20200622__us-gaap--TypeOfArrangementAxis__custom--UnderwritingAgreementMember__us-gaap--SubsidiarySaleOfStockAxis__custom--UnderwrittenOfferingMember_pdd"&gt;7.0%
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;of the public offering price. The net proceeds
to the Company from the Underwritten Offering, after deducting the underwriting discount and estimated offering expenses payable by the
Company, were approximately $&lt;span id="xdx_900_eus-gaap--ProceedsFromIssuanceOfCommonStock_pn5n6_c20200621__20200622__us-gaap--TypeOfArrangementAxis__custom--UnderwritingAgreementMember__us-gaap--SubsidiarySaleOfStockAxis__custom--UnderwrittenOfferingMember_zQIpLXo9Qdhi"&gt;9.1
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Pursuant
to the Underwriting Agreement, until December 31, 2020, the Underwriter had a right of first refusal to act as sole underwriter, initial
purchaser, placement/selling agent, or arranger, as the case may be, on any new financing for the Company (excluding equipment lease
financings, loans or grants from governmental authorities or in connection with government programs and financings relating to or sales
of tax attributes) during such period. The Underwriter common stock the sole right to determine whether or not any other broker dealer
shall have the right to participate in any such offering and the economic terms of any such participation.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;i&gt;&lt;span style="text-decoration: underline"&gt;January
2021 Registered Direct Offering&lt;/span&gt;&lt;/i&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
January 22, 2021, the Company entered into a Securities Purchase Agreement (the &#x201c;January 2021 Purchase Agreement&#x201d;) with several
institutional investors, pursuant to which the Company agreed to issue and sell, in a registered direct offering (the &#x201c;January
2021 Offering&#x201d;), an aggregate of &lt;span id="xdx_900_eus-gaap--StockIssuedDuringPeriodSharesNewIssues_pid_c20210121__20210122__us-gaap--TypeOfArrangementAxis__custom--UnderwritingAgreementMember__us-gaap--SubsidiarySaleOfStockAxis__custom--JanuaryRegisteredDirectOfferingMember_zasU5swSYTMh"&gt;25,925,925
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;shares of the Company&#x2019;s common stock at
an offering price of $&lt;span id="xdx_904_eus-gaap--SharePrice_iI_pid_c20210122__us-gaap--TypeOfArrangementAxis__custom--UnderwritingAgreementMember__us-gaap--SubsidiarySaleOfStockAxis__custom--JanuaryRegisteredDirectOfferingMember_zr11OwB61xAk"&gt;1.35
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;per share for gross proceeds of approximately
$&lt;span id="xdx_907_eus-gaap--ProceedsFromIssuanceOfCommonStock_pn6n6_c20210121__20210122__us-gaap--TypeOfArrangementAxis__custom--UnderwritingAgreementMember__us-gaap--SubsidiarySaleOfStockAxis__custom--JanuaryRegisteredDirectOfferingMember_zd15X3MYAhDf"&gt;35
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million before the deduction of the January 2021
Placement Agents (as defined below) fee and offering expenses. The January 2021 Purchase Agreement contains customary representations,
warranties and agreements by the Company and customary conditions to closing. The closing of the January 2021 Offering occurred on January
26, 2021.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;




&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span id="xdx_907_ecustom--PlacementAgentFeeDescription_c20210121__20210122__us-gaap--TypeOfArrangementAxis__custom--UnderwritingAgreementMember__us-gaap--SubsidiarySaleOfStockAxis__custom--JanuaryRegisteredDirectOfferingMember" style="font: 10pt Times New Roman, Times, Serif"&gt;In
connection with the January 2021 Offering, the Company entered into a placement agent agreement (the &#x201c;January 2021 Placement Agent
Agreement&#x201d;) with A.G.P./Alliance Global Partners (together with Brookline Capital Markets, the &#x201c;January 2021 Placement Agents&#x201d;)
pursuant to which the Company agreed to pay the January 2021 Placement Agents a cash fee equal to 7% of the aggregate gross proceeds
raised from the sale of the securities sold in the January 2021 Offering and reimburse the January 2021 Placement Agents for certain
of their expenses in an amount not to exceed $82,500.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;i&gt;&lt;span style="text-decoration: underline"&gt;March
2021 Registered Direct Offering&lt;/span&gt;&lt;/i&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
March 31, 2021, the Company entered into a Securities Purchase Agreement (the &#x201c;March 2021 Purchase Agreement&#x201d;) with several
institutional investors, pursuant to which the Company agreed to issue and sell, in a registered direct offering (the &#x201c;March 2021
Offering&#x201d;), an aggregate of &lt;span id="xdx_90F_eus-gaap--StockIssuedDuringPeriodSharesNewIssues_pid_c20210301__20210331__us-gaap--TypeOfArrangementAxis__custom--UnderwritingAgreementMember__us-gaap--SubsidiarySaleOfStockAxis__custom--MarchRegisteredDirectOfferingMember_zdtgwFzakQy9"&gt;11,538,462
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;shares of the Company&#x2019;s common stock, at
an offering price of $&lt;span id="xdx_904_eus-gaap--SharePrice_iI_pid_c20210331__us-gaap--TypeOfArrangementAxis__custom--UnderwritingAgreementMember__us-gaap--SubsidiarySaleOfStockAxis__custom--MarchRegisteredDirectOfferingMember_z7sC1OPpVPib"&gt;1.30
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;per share for gross proceeds of approximately
$&lt;span id="xdx_90B_eus-gaap--ProceedsFromIssuanceOfCommonStock_pn6n6_c20210301__20210331__us-gaap--TypeOfArrangementAxis__custom--UnderwritingAgreementMember__us-gaap--SubsidiarySaleOfStockAxis__custom--MarchRegisteredDirectOfferingMember_zXxKK5h5EZul"&gt;15
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million before the deduction of the placement
agents fee and offering expenses. The shares were offered by the Company pursuant to the 2021 Registration Statement. The closing of
the Offering occurred on April 5, 2021.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span id="xdx_908_ecustom--PlacementAgentFeeDescription_c20210301__20210331__us-gaap--TypeOfArrangementAxis__custom--UnderwritingAgreementMember__us-gaap--SubsidiarySaleOfStockAxis__custom--MarchRegisteredDirectOfferingMember_zNVsqgMVK1J7" style="font: 10pt Times New Roman, Times, Serif"&gt;In
connection with the March 2021 Offering, the Company entered into a placement agent agreement (the &#x201c;March 2021 Placement Agent
Agreement&#x201d;) with A.G.P./Alliance Global Partners, as lead placement agent (&#x201c;AGP,&#x201d; and together with JonesTrading Institutional
Services LLC and Brookline Capital Markets, a division of Arcadia Securities, LLC, serving as co-placement agents, the &#x201c;March 2021
Placement Agents&#x201d;) pursuant to which the Company agreed to pay the March 2021 Placement Agents an aggregate cash fee equal to 7%
of the aggregate gross proceeds raised from the sale of the securities sold in the Offering and reimburse the Placement Agents for certain
of their expenses in an amount not to exceed $82,500.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Under
the March 2021 Purchase Agreement and March 2021 Placement Agent Agreement, the Company and its subsidiaries are prohibited, for a period
of 90 days after the closing, from entering into any agreement to issue or announcing any issuance or proposed issuance of common stock
or any other securities that are at any time convertible into, or exercisable or exchangeable for, or otherwise entitle the holder thereof
to receive common stock without the prior written consent of AGP or the investors participating in the offering. For purposes of this
offering, AGP and the investors from the Company&#x2019;s January 2021 Offering waived a similar 90-day restriction in the placement agent
agreement and purchase agreement for that transaction.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;i&gt;&lt;span style="text-decoration: underline"&gt;LPC
Purchase Agreement&lt;/span&gt;&lt;/i&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
September 8, 2020, the Company entered into a purchase agreement (the &#x201c;LPC Purchase Agreement&#x201d;) and a Registration Rights
Agreement (the &#x201c;Registration Rights Agreement&#x201d;) with Lincoln Park Capital Fund, LLC (&#x201c;Lincoln Park&#x201d;), pursuant
to which, upon the terms and subject to the conditions and limitations set forth therein, the Company has the right to sell to Lincoln
Park up to $&lt;span id="xdx_905_eus-gaap--StockIssuedDuringPeriodSharesNewIssues_pn5n6_c20200907__20200908__us-gaap--TypeOfArrangementAxis__custom--LPCPurchaseAgreementMember__dei--LegalEntityAxis__custom--LincolnParkCapitalFundLLCMember_zjznHtlrf8kh"&gt;26.0
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million of shares of the Company&#x2019;s common
stock at the Company&#x2019;s discretion as described below (the &#x201c;LPC Offering&#x201d;). During 2020, the Company sold and issued
an aggregate of &lt;span id="xdx_90C_eus-gaap--StockIssuedDuringPeriodSharesNewIssues_pn5n6_c20200101__20201231__us-gaap--TypeOfArrangementAxis__custom--LPCPurchaseAgreementMember__dei--LegalEntityAxis__custom--LincolnParkCapitalFundLLCMember_z85zqYLDSQCd"&gt;3.3
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million shares, including the &lt;span id="xdx_905_eus-gaap--StockIssuedDuringPeriodSharesNewIssues_c20200907__20200908__us-gaap--TypeOfArrangementAxis__custom--LPCPurchaseAgreementMember__dei--LegalEntityAxis__custom--LincolnParkCapitalFundLLCMember__us-gaap--StatementEquityComponentsAxis__custom--LPCCommitmentSharesMember_pdd"&gt;437,828
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;commitment shares, under the LPC Purchase Agreement,
receiving approximately $&lt;span id="xdx_90F_eus-gaap--ProceedsFromIssuanceOfCommonStock_pn5n6_c20200101__20201231__us-gaap--TypeOfArrangementAxis__custom--LPCPurchaseAgreementMember__dei--LegalEntityAxis__custom--LincolnParkCapitalFundLLCMember_ztWQLGUmWN6"&gt;2.2
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million in gross proceeds. On January
21, 2021, the Company terminated the LPC Purchase Agreement. The Company did not sell any shares under the LPC Purchase Agreement
in 2021.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

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    <CLSN:ShelfRegistrationStatementAmount
      contextRef="From2021-03-182021-03-19"
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      unitRef="USD">100000000</CLSN:ShelfRegistrationStatementAmount>
    <CLSN:AggregateOfferingPrices
      contextRef="From2018-12-022018-12-04_custom_CapitalOnDemandTMSalesAgreementMember"
      decimals="-5"
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      contextRef="From2020-01-012020-06-30_custom_CapitalOnDemandAgreementMember"
      decimals="-5"
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    <us-gaap:ProceedsFromIssuanceOfCommonStock
      contextRef="From2020-01-012020-06-30_custom_CapitalOnDemandAgreementMember"
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      unitRef="USD">3500000</us-gaap:ProceedsFromIssuanceOfCommonStock>
    <us-gaap:StockIssuedDuringPeriodSharesNewIssues
      contextRef="From2021-01-012021-03-31_custom_CapitalOnDemandAgreementMember"
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    <us-gaap:ProceedsFromIssuanceOfCommonStock
      contextRef="From2021-01-012021-03-31_custom_CapitalOnDemandAgreementMember"
      decimals="-5"
      unitRef="USD">6900000</us-gaap:ProceedsFromIssuanceOfCommonStock>
    <us-gaap:StockIssuedDuringPeriodSharesNewIssues
      contextRef="From2020-02-262020-02-27_custom_SecuritiesPurchaseAgreementMember"
      decimals="INF"
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    <us-gaap:SharesIssuedPricePerShare
      contextRef="AsOf2020-02-27_custom_SecuritiesPurchaseAgreementMember"
      decimals="INF"
      unitRef="USDPShares">1.05</us-gaap:SharesIssuedPricePerShare>
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      contextRef="From2020-02-262020-02-27_custom_SecuritiesPurchaseAgreementMember"
      decimals="-5"
      unitRef="USD">4800000</us-gaap:ProceedsFromIssuanceOfCommonStock>
    <us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight
      contextRef="AsOf2020-02-27_custom_SecuritiesPurchaseAgreementMember_custom_OriginalWarrantsMember"
      decimals="INF"
      unitRef="Shares">2971428</us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight>
    <us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1
      contextRef="AsOf2020-02-27_custom_SecuritiesPurchaseAgreementMember_custom_OriginalWarrantsMember"
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      contextRef="AsOf2020-03-12_custom_ExchangeAgreementsMember_us-gaap_WarrantMember"
      decimals="INF"
      unitRef="USDPShares">1.24</us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1>
    <us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight
      contextRef="AsOf2020-03-12_custom_ExchangeAgreementsMember_us-gaap_WarrantMember"
      decimals="INF"
      unitRef="Shares">3200000</us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight>
    <us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight
      contextRef="AsOf2021-06-30_custom_ExchangeAgreementsMember"
      decimals="-5"
      unitRef="Shares">1200000</us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight>
    <us-gaap:ProceedsFromIssuanceOfWarrants
      contextRef="From2021-01-012021-06-30_custom_ExchangeAgreementsMember"
      decimals="-5"
      unitRef="USD">1500000</us-gaap:ProceedsFromIssuanceOfWarrants>
    <us-gaap:StockIssuedDuringPeriodSharesNewIssues
      contextRef="From2020-06-212020-06-22_custom_UnderwritingAgreementMember_custom_UnderwrittenOfferingMember"
      decimals="INF"
      unitRef="Shares">2666667</us-gaap:StockIssuedDuringPeriodSharesNewIssues>
    <us-gaap:SharePrice
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      contextRef="AsOf2020-06-22_custom_UnderwritingAgreementMember_custom_UnderwrittenOfferingMember"
      decimals="INF"
      unitRef="USDPShares">3.75</us-gaap:SharesIssuedPricePerShare>
    <CLSN:UnderwritingDiscountPricePerShare
      contextRef="From2020-06-212020-06-22_custom_UnderwritingAgreementMember_custom_UnderwrittenOfferingMember"
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      unitRef="USDPShares">0.2625</CLSN:UnderwritingDiscountPricePerShare>
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    <us-gaap:StockIssuedDuringPeriodSharesNewIssues
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    <us-gaap:SharePrice
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    <CLSN:PlacementAgentFeeDescription contextRef="From2021-01-212021-01-22_custom_UnderwritingAgreementMember_custom_JanuaryRegisteredDirectOfferingMember">In
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Agreement&#x201d;) with A.G.P./Alliance Global Partners (together with Brookline Capital Markets, the &#x201c;January 2021 Placement Agents&#x201d;)
pursuant to which the Company agreed to pay the January 2021 Placement Agents a cash fee equal to 7% of the aggregate gross proceeds
raised from the sale of the securities sold in the January 2021 Offering and reimburse the January 2021 Placement Agents for certain
of their expenses in an amount not to exceed $82,500.</CLSN:PlacementAgentFeeDescription>
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      contextRef="AsOf2021-03-31_custom_UnderwritingAgreementMember_custom_MarchRegisteredDirectOfferingMember"
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      contextRef="From2021-03-012021-03-31_custom_UnderwritingAgreementMember_custom_MarchRegisteredDirectOfferingMember"
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    <CLSN:PlacementAgentFeeDescription contextRef="From2021-03-012021-03-31_custom_UnderwritingAgreementMember_custom_MarchRegisteredDirectOfferingMember">In
connection with the March 2021 Offering, the Company entered into a placement agent agreement (the &#x201c;March 2021 Placement Agent
Agreement&#x201d;) with A.G.P./Alliance Global Partners, as lead placement agent (&#x201c;AGP,&#x201d; and together with JonesTrading Institutional
Services LLC and Brookline Capital Markets, a division of Arcadia Securities, LLC, serving as co-placement agents, the &#x201c;March 2021
Placement Agents&#x201d;) pursuant to which the Company agreed to pay the March 2021 Placement Agents an aggregate cash fee equal to 7%
of the aggregate gross proceeds raised from the sale of the securities sold in the Offering and reimburse the Placement Agents for certain
of their expenses in an amount not to exceed $82,500.</CLSN:PlacementAgentFeeDescription>
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    <us-gaap:StockIssuedDuringPeriodSharesNewIssues
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    <us-gaap:ProceedsFromIssuanceOfCommonStock
      contextRef="From2020-01-012020-12-31_custom_LPCPurchaseAgreementMember_custom_LincolnParkCapitalFundLLCMember"
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      unitRef="USD">2200000</us-gaap:ProceedsFromIssuanceOfCommonStock>
    <us-gaap:DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock contextRef="From2021-01-01to2021-06-30">&lt;p id="xdx_80A_eus-gaap--DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock_zlOPbZ1JNyq4" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
13. &lt;span id="xdx_827_z8STTSt0mLsi"&gt;Stock-Based Compensation&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
Company has long-term compensation plans that permit the granting of equity-based awards in the form of stock options, restricted stock,
restricted stock units, stock appreciation rights, other stock awards, and performance awards.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;At
the 2018 Annual Stockholders Meeting of the Company held on May 15, 2018, stockholders approved the Celsion Corporation 2018 Stock Incentive
Plan (the &#x201c;2018 Plan&#x201d;). The 2018 Plan, as adopted, permits the granting of &lt;span id="xdx_900_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_c20210630__us-gaap--PlanNameAxis__custom--TwoThousandAndEighteenStockIncentivePlanMember_pdd"&gt;2,700,000
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;shares of Celsion common stock as equity awards
in the form of incentive stock options, nonqualified stock options, restricted stock, restricted stock units, stock appreciation rights,
other stock awards, performance awards, or in any combination of the foregoing. At the 2019 Annual Stockholders Meeting of the Company
held on May 14, 2019, stockholders approved an amendment to the 2018 Plan whereby the Company increased the number of common stock shares
available by &lt;span id="xdx_906_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_iI_c20190514__us-gaap--PlanNameAxis__custom--TwoThousandAndEighteenStockIncentivePlanMember__srt--RangeAxis__srt--MinimumMember_zLqi5XRg0ysh"&gt;1,200,000
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;to a total of &lt;span id="xdx_90E_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_iI_c20190514__us-gaap--PlanNameAxis__custom--TwoThousandAndEighteenStockIncentivePlanMember__srt--RangeAxis__srt--MaximumMember_z1yrVQy1CBnh"&gt;3,900,000
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;under the 2018 Plan, as amended. Prior to the
adoption of the 2018 Plan, the Company had maintained the Celsion Corporation 2007 Stock Incentive Plan (the &#x201c;2007 Plan&#x201d;).
At the 2020 Annual Stockholders Meeting of the Company held on June 15, 2020, stockholders approved an amendment to the 2018 Plan, as
previously amended, whereby the Company increased the number of shares of common stock available by &lt;span id="xdx_90D_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_c20200615__us-gaap--PlanNameAxis__custom--TwoThousandAndEighteenStockIncentivePlanMember__srt--RangeAxis__srt--MinimumMember_pdd"&gt;2,500,000
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;to a total of &lt;span id="xdx_90F_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_c20200615__us-gaap--PlanNameAxis__custom--TwoThousandAndEighteenStockIncentivePlanMember__srt--RangeAxis__srt--MaximumMember_pdd"&gt;6,400,000
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;under the 2018 Plan, as amended. At the 2021
Annual Stockholders Meeting of the Company held on June 10, 2020, stockholders approved an amendment to the 2018 Plan, as previously
amended, whereby the Company increased the number of shares of common stock available by &lt;span id="xdx_902_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_iI_c20210610__us-gaap--PlanNameAxis__custom--TwoThousandAndEighteenStockIncentivePlanMember__srt--RangeAxis__srt--MinimumMember_zkv7ydFVwj2"&gt;7,700,000
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;to a total of &lt;span id="xdx_90F_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_iI_c20210610__us-gaap--PlanNameAxis__custom--TwoThousandAndEighteenStockIncentivePlanMember__srt--RangeAxis__srt--MaximumMember_z0Zgx5xDVRQ6"&gt;14,100,000
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;under the 2018 Plan, as amended.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
Company has issued stock awards to employees and directors in the form of stock options and restricted stock. &lt;span id="xdx_901_ecustom--StockOptionsStrikePriceDescription_c20210101__20210630__us-gaap--PlanNameAxis__custom--TwoThousandSevenStockIncentivePlanMember"&gt;Options
are generally granted with strike prices equal to the fair market value of a share of Celsion common stock on the date of grant. Incentive
stock options may be granted to purchase shares of common stock at a price not less than 100% of the fair market value of the underlying
shares on the date of grant, provided that the exercise price of any incentive stock option granted to an eligible employee owning more
than 10% of the outstanding stock of Celsion must be at least 110% of such fair market value on the date of grant. Only officers and
key employees may receive incentive stock options.&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;




&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Option
and restricted stock awards vest upon terms determined by the Compensation Committee of the Board of Directors and are subject to accelerated
vesting in the event of a change of control or certain terminations of employment. The Company issues new shares to satisfy its obligations
from the exercise of options or the grant of restricted stock awards.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
September 28, 2018, and again on February 19, 2019, the Compensation Committee of the Board of Directors approved the grant of (i)
inducement stock options (the &#x201c;Inducement Option Grants&#x201d;) to purchase a total of &lt;span id="xdx_90C_eus-gaap--SharesIssued_c20180928__us-gaap--PlanNameAxis__custom--InducementOptionGrantsMember__srt--TitleOfIndividualAxis__custom--FiveNewEmployeesMember__us-gaap--StatementEquityComponentsAxis__us-gaap--CommonStockMember_pdd"&gt;164,004 &lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;and &lt;span id="xdx_907_eus-gaap--SharesIssued_c20190219__us-gaap--PlanNameAxis__custom--InducementOptionGrantsMember__srt--TitleOfIndividualAxis__custom--FiveNewEmployeesMember__us-gaap--StatementEquityComponentsAxis__us-gaap--CommonStockMember_pdd"&gt;140,004 &lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;shares
of Celsion common stock, respectively and (ii) inducement restricted stock awards (the &#x201c;Inducement Stock Grants&#x201d;)
totaling &lt;span id="xdx_90D_eus-gaap--SharesIssued_c20180928__us-gaap--PlanNameAxis__custom--InducementOptionGrantsMember__srt--TitleOfIndividualAxis__custom--FiveNewEmployeesMember__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_pdd"&gt;19,000 &lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;and &lt;span id="xdx_906_eus-gaap--SharesIssued_c20190219__us-gaap--PlanNameAxis__custom--InducementOptionGrantsMember__srt--TitleOfIndividualAxis__custom--FiveNewEmployeesMember__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_pdd"&gt;13,000 &lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;shares
of Celsion common stock to five new employees collectively. Each award has a grant date of the date of grant. Each Inducement Option
Grant has an exercise price per share equal to $&lt;span id="xdx_908_eus-gaap--ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_c20180927__20180928__us-gaap--PlanNameAxis__custom--InducementOptionGrantsMember__srt--TitleOfIndividualAxis__custom--FiveNewEmployeesMember_pdd"&gt;2.77 &lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;and
$&lt;span id="xdx_907_eus-gaap--ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_c20190218__20190219__us-gaap--PlanNameAxis__custom--InducementOptionGrantsMember__srt--TitleOfIndividualAxis__custom--FiveNewEmployeesMember_pdd"&gt;2.18 &lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;which
represents the closing price of Celsion&#x2019;s common stock as reported by Nasdaq on September 28, 2018 and February 19, 2019,
respectively. Each Inducement Option Grant will vest over &lt;span id="xdx_901_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_dc_c20190218__20190219__us-gaap--PlanNameAxis__custom--InducementOptionGrantsMember__srt--TitleOfIndividualAxis__custom--FiveNewEmployeesMember_zg6B4KigMCR1"&gt;three years&lt;/span&gt;, with one-third vesting on the one-year anniversary of the
employee&#x2019;s first day of employment with the Company and one-third vesting on the second and third anniversaries thereafter,
subject to the new employee&#x2019;s continued service relationship with the Company on each such date. Each Inducement Option Grant
has a ten-year term and is subject to the terms and conditions of the applicable stock option agreement. Each of Inducement Stock
Grant vested on the one-year anniversary of the employee&#x2019;s first day of employment with the Company is subject to the new
employee&#x2019;s continued service relationship with the Company through such date and is subject to the terms and conditions of the
applicable restricted stock agreement.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;As
of June 30, 2021, there were a total of &lt;span id="xdx_907_eus-gaap--CommonStockCapitalSharesReservedForFutureIssuance_c20210630__us-gaap--PlanNameAxis__custom--TwoThousandAndEighteenStockIncentivePlanMember_pdd"&gt;14,198,424
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;shares of Celsion common stock reserved for
issuance under the 2018 Plan, which were comprised of &lt;span id="xdx_909_eus-gaap--CommonStockCapitalSharesReservedForFutureIssuance_c20210630__us-gaap--AwardTypeAxis__custom--EquityStockAwardsMember__srt--StatementScenarioAxis__custom--GrantedUnderTwoThousandEighteenPlanAndTwoThousandSevenPlanMember_pdd"&gt;6,548,325
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;shares of Celsion common stock subject to equity
awards previously granted under the 2018 Plan and 2007 Plan and &lt;span id="xdx_90E_eus-gaap--CommonStockCapitalSharesReservedForFutureIssuance_iI_c20210630__us-gaap--PlanNameAxis__custom--TwoThousandAndEighteenPlanMember_z956AaBaeSe6"&gt;7,650,099
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;shares of Celsion common stock available for
future issuance under the 2018 Plan. As of June 30, 2021, there were a total of &lt;span id="xdx_90D_eus-gaap--CommonStockCapitalSharesReservedForFutureIssuance_iI_c20210630__us-gaap--AwardTypeAxis__custom--InducementAwardsMember_zxqedVkaaaz3"&gt;140,004
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;shares of Celsion common stock subject to outstanding
inducement awards.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Total
compensation cost related to stock options and restricted stock awards amounted to $&lt;span id="xdx_90D_eus-gaap--AllocatedShareBasedCompensationExpense_pp0p0_c20210401__20210630__us-gaap--AwardTypeAxis__custom--EmployeeStockOptionAndRestrictedStockAwardsMember_zOmXtm9Xb4T7"&gt;793,619
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;and $&lt;span id="xdx_906_eus-gaap--AllocatedShareBasedCompensationExpense_pp0p0_c20200401__20200630__us-gaap--AwardTypeAxis__custom--EmployeeStockOptionAndRestrictedStockAwardsMember_zmb9KxLh1xzg"&gt;578,761
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;for the three-month periods ended June 30, 2021
and 2020, respectively. Of these amounts, $&lt;span id="xdx_902_eus-gaap--AllocatedShareBasedCompensationExpense_pp0p0_c20210401__20210630__us-gaap--AwardTypeAxis__custom--EmployeeStockOptionAndRestrictedStockAwardsMember__us-gaap--IncomeStatementLocationAxis__us-gaap--ResearchAndDevelopmentExpenseMember_zvAXbhtQ8ii9"&gt;299,581
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;and $&lt;span id="xdx_90B_eus-gaap--AllocatedShareBasedCompensationExpense_pp0p0_c20200401__20200630__us-gaap--AwardTypeAxis__custom--EmployeeStockOptionAndRestrictedStockAwardsMember__us-gaap--IncomeStatementLocationAxis__us-gaap--ResearchAndDevelopmentExpenseMember_zo7odFA6jb2j"&gt;200,186
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;was charged to research and development during
the three-month periods ended June 30, 2021 and 2020, respectively, and $&lt;span id="xdx_908_eus-gaap--AllocatedShareBasedCompensationExpense_pp0p0_c20210401__20210630__us-gaap--AwardTypeAxis__custom--EmployeeStockOptionAndRestrictedStockAwardsMember__us-gaap--IncomeStatementLocationAxis__us-gaap--GeneralAndAdministrativeExpenseMember_zsTEVS685Fp7"&gt;494,038
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;and $&lt;span id="xdx_908_eus-gaap--AllocatedShareBasedCompensationExpense_pp0p0_c20200401__20200630__us-gaap--AwardTypeAxis__custom--EmployeeStockOptionAndRestrictedStockAwardsMember__us-gaap--IncomeStatementLocationAxis__us-gaap--GeneralAndAdministrativeExpenseMember_z0BVdkASGh58"&gt;378,575
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;was charged to general and administrative expenses
during the three-month periods ended June 30, 2021 and 2020, respectively.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Total
compensation cost related to stock options and restricted stock awards amounted to $&lt;span id="xdx_90B_eus-gaap--AllocatedShareBasedCompensationExpense_c20210101__20210630__us-gaap--AwardTypeAxis__custom--EmployeeStockOptionAndRestrictedStockAwardsMember_pp0p0"&gt;2,372,945
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;and $&lt;span id="xdx_909_eus-gaap--AllocatedShareBasedCompensationExpense_c20200101__20200630__us-gaap--AwardTypeAxis__custom--EmployeeStockOptionAndRestrictedStockAwardsMember_pp0p0"&gt;1,030,726
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;for the six-month periods ended June 30, 2021
and 2020, respectively. Of these amounts, $&lt;span id="xdx_904_eus-gaap--AllocatedShareBasedCompensationExpense_c20210101__20210630__us-gaap--AwardTypeAxis__custom--EmployeeStockOptionAndRestrictedStockAwardsMember__us-gaap--IncomeStatementLocationAxis__us-gaap--ResearchAndDevelopmentExpenseMember_pp0p0"&gt;882,088
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;and $&lt;span id="xdx_90B_eus-gaap--AllocatedShareBasedCompensationExpense_c20200101__20200630__us-gaap--AwardTypeAxis__custom--EmployeeStockOptionAndRestrictedStockAwardsMember__us-gaap--IncomeStatementLocationAxis__us-gaap--ResearchAndDevelopmentExpenseMember_pp0p0"&gt;378,122
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;was charged to research and development during
the six-month periods ended June 30, 2021 and 2020, respectively, and $&lt;span id="xdx_900_eus-gaap--AllocatedShareBasedCompensationExpense_c20210101__20210630__us-gaap--AwardTypeAxis__custom--EmployeeStockOptionAndRestrictedStockAwardsMember__us-gaap--IncomeStatementLocationAxis__us-gaap--GeneralAndAdministrativeExpenseMember_pp0p0"&gt;1,490,857
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;and $&lt;span id="xdx_902_eus-gaap--AllocatedShareBasedCompensationExpense_c20200101__20200630__us-gaap--AwardTypeAxis__custom--EmployeeStockOptionAndRestrictedStockAwardsMember__us-gaap--IncomeStatementLocationAxis__us-gaap--GeneralAndAdministrativeExpenseMember_pp0p0"&gt;652,604
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;was charged to general and administrative expenses
during the six-month periods ended June 30, 2021 and 2020, respectively.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;As
of June 30, 2021, there was $&lt;span id="xdx_903_eus-gaap--EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_iI_pn5n6_c20210630_zNzij1mXPAQe"&gt;3.2
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million of total unrecognized compensation cost
related to non-vested stock-based compensation arrangements. That cost is expected to be recognized over a weighted-average period of
&lt;span id="xdx_906_eus-gaap--EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_dtY_c20210101__20210630_zE9oLHUCHx4d"&gt;1.2
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;years. The weighted average grant date fair values
of the stock options granted was $&lt;span id="xdx_907_eus-gaap--ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_c20210101__20210630_pdd"&gt;1.98
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;and $&lt;span id="xdx_90A_eus-gaap--ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_c20200101__20200630_pdd"&gt;3.10
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;during the six-month periods ended June 30, 2021
and 2020, respectively. A summary of stock option awards and restricted stock grants for the three-months ended June 30, 2021 is presented
below:&lt;/span&gt;&lt;/p&gt;

&lt;p id="xdx_897_ecustom--SummaryOfStockOptionAndRestrictedStockAwardsTableTextBlock_zdNvlcpS5MWa" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span id="xdx_8B5_zdwapitkW4Tb" style="font: 10pt Times New Roman, Times, Serif; display: none"&gt;Summary
of Stock Option Awards and Restricted Stock Grants&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Stock
    Options&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Restricted
    Stock Awards&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Weighted&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Average&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Options&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Outstanding&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Weighted&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Average&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Exercise&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Price&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Non-vested&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Restricted&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Stock&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Outstanding&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Weighted&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Average&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Grant&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Date&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Fair
                                            Value&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Contractual&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Terms
                                            of&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Equity&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Awards&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;(in
                                            years)&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 35%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Equity awards outstanding at January
    1, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_987_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_iS_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zs8NivCzWEJl" style="width: 9%; text-align: right" title="Number Outstanding, Outstanding, Beginning balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;4,624,725&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98E_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_iS_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zjNzVF9yzIq2" style="width: 9%; text-align: right" title="Weighted Average Exercise Price, Outstanding, Beginning balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2.77&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_984_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_iS_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_zqUlMKUubbcj" style="width: 9%; text-align: right" title="Number Outstanding, Non-vested stock awards, Outstanding, Beginning balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2,750&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_987_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_iS_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_z740gWcrLMA3" style="width: 9%; text-align: right" title="Weighted Average Grant Date Fair Value, Non-vested stock awards, Outstanding, Beginning balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;0.89&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 9%; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Equity awards granted&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_986_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_pdd" style="text-align: right" title="Number Outstanding, Options granted"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2,154,000&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_986_eus-gaap--ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_pdd" style="text-align: right" title="Weighted Average Exercise Price, Options granted"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2.18&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_987_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_pdd" style="text-align: right" title="Number Outstanding, Non-vested stock awards, Granted"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;7,000&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98E_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_pdd" style="text-align: right" title="Weighted Average Grant Date Fair Value, Non-vested stock awards, Granted"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;1.38&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Equity awards exercised or vested and issued&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_980_eus-gaap--StockIssuedDuringPeriodSharesStockOptionsExercised_iN_di_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zz9vwH6dwF9d" style="text-align: right" title="Number Outstanding, Options exercised or vested and issued"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;(7,500&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;)&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_985_eus-gaap--ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_pdd" style="text-align: right" title="Weighted Average Exercise Price, Options exercised or vested and issued"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;0.63&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_984_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_pdd" style="text-align: right" title="Number Outstanding, Non-vested stock awards, exercised or vested and issued"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1157"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98A_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_pdd" style="text-align: right" title="Weighted Average Grant Date Fair Value, Non-vested stock awards, exercised or vested and issued"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1159"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Equity awards forfeited,
    cancelled or expired&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_983_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod_iN_di_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zfFZt1TlTe2f" style="border-bottom: Black 1.5pt solid; text-align: right" title="Number Outstanding, Options canceled or expired"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;(92,646&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;)&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_981_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_pdd" style="padding-bottom: 1.5pt; text-align: right" title="Weighted Average Exercise Price, Options canceled or expired"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2.69&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98B_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_pdd" style="border-bottom: Black 1.5pt solid; text-align: right" title="Number Outstanding, Non-vested stock awards, Forfeited"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1165"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98E_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_pdd" style="padding-bottom: 1.5pt; text-align: right" title="Weighted Average Grant Date Fair Value, Non-vested stock awards, Forfeited"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1167"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Equity awards outstanding
    at June 30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98C_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_iE_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zZRQKzEajN1k" style="border-bottom: Black 2.5pt double; text-align: right" title="Number Outstanding, Outstanding, Ending balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;6,678,579&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98F_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_iE_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zoAmbc7LD97b" style="padding-bottom: 2.5pt; text-align: right" title="Weighted Average Exercise Price, Outstanding, Ending balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2.58&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98F_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_iE_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_z2MhcObQKuDf" style="border-bottom: Black 2.5pt double; text-align: right" title="Number Outstanding, Non-vested stock awards, Outstanding, Ending balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;9,750&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_985_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_iE_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_zkzFCAGm1tvg" style="padding-bottom: 2.5pt; text-align: right" title="Weighted Average Grant Date Fair Value, Non-vested stock awards, Outstanding, Ending balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;1.27&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;span id="xdx_905_eus-gaap--SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_dtY_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zbBH4fvhOS5i" style="font-family: Times New Roman, Times, Serif"&gt;8.0&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Aggregate intrinsic
    value of outstanding equity awards at June 30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_986_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_iE_pp0p0_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zgaOVGFesug1" style="border-bottom: Black 2.5pt double; text-align: right" title="Aggregate Intrinsic Value, Outstanding, Ending balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;12,145&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98C_eus-gaap--SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueOutstanding_iE_pp0p0_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_z7Sj2pid0O4k" style="border-bottom: Black 2.5pt double; text-align: right" title="Aggregate Intrinsic Value, Non-vested stock awards, Outstanding, Ending balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;12,383&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Equity awards exercisable
    at June 30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_980_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_iE_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zCGoAEnaXIjc" style="border-bottom: Black 2.5pt double; text-align: right" title="Number Outstanding, Exercisable, Ending balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;4,329,286&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98B_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice_iE_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zrk5BnhfHVWh" style="padding-bottom: 2.5pt; text-align: right" title="Weighted Average Exercise Price, Exercisable, Ending balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2.73&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;span id="xdx_90A_eus-gaap--SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1_dtY_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_ziiBCIpqp7bb" style="font-family: Times New Roman, Times, Serif"&gt;7.8&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Aggregate intrinsic
    value of equity awards exercisable at June 30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_984_eus-gaap--SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1_iE_pp0p0_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zY55dMDQ9Goa" style="border-bottom: Black 2.5pt double; text-align: right" title="Aggregate Intrinsic Value, Exercisable, Ending balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;1,650&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p id="xdx_8A1_z5CbKCmiKN2l" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;




&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p id="xdx_89C_eus-gaap--ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock_zvVrpPRBlNSd" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
fair values of stock options granted were estimated at the date of grant using the Black-Scholes option pricing model. The Black-Scholes
model was originally developed for use in estimating the fair value of traded options, which have different characteristics from Celsion&#x2019;s
stock options. The model is also sensitive to changes in assumptions, which can materially affect the fair value estimate. The Company
used the following assumptions for determining the fair value of options granted under the Black-Scholes option pricing model:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8B1_zAvmRlNBERij" style="display: none"&gt;Schedule
of Assumptions Used to Determine Fair Value of Options Granted&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"/&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: White"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td colspan="5" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Six
                                            Months Ended June 30, &#160;&lt;/b&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: White"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;2021&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;2020&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 60%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Risk-free
    interest rate&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 2%"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 16%; text-align: right"&gt;&lt;span id="xdx_90C_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum_pid_dp_c20210101__20210630_zbHSZSVsxGng" style="font: 10pt Times New Roman, Times, Serif"&gt;1.56
                                            &lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;to &lt;span id="xdx_90C_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum_pid_dp_c20210101__20210630_z61dC6LUBpG7"&gt;1.74&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 2%"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 16%; text-align: right"&gt;&lt;span id="xdx_90D_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum_pid_dp_c20200101__20200630_zsBDu6znfba7" style="font: 10pt Times New Roman, Times, Serif"&gt;0.71
                                            &lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;to &lt;span id="xdx_903_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum_pid_dp_c20200101__20200630_z4h3tRgTmWW3"&gt;1.33&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: White"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Expected
    volatility&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span id="xdx_908_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMinimum_pid_dp_c20210101__20210630_zOviDMd7lCtf" style="font: 10pt Times New Roman, Times, Serif"&gt;106.8
                                            &lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;to &lt;span id="xdx_904_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum_pid_dp_c20210101__20210630_zY4Mod2WgDI"&gt;113.0&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span id="xdx_901_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMinimum_pid_dp_c20200101__20200630_zNHIZ28tcg1d" style="font: 10pt Times New Roman, Times, Serif"&gt;100.4
                                            &lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;to &lt;span id="xdx_904_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum_pid_dp_c20200101__20200630_zmTjM8Vk6KF7"&gt;104.2&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Expected
    life (in years)&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span id="xdx_90D_eus-gaap--SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_dtY_c20210101__20210630__srt--RangeAxis__srt--MinimumMember_zUnxBpAcWXsk" style="font: 10pt Times New Roman, Times, Serif"&gt;7.5
                                            &lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;to &lt;span id="xdx_904_eus-gaap--SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_dtY_c20210101__20210630__srt--RangeAxis__srt--MaximumMember_ziitPTyChS7f"&gt;10.0&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_903_eus-gaap--SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_dtY_c20200101__20200630__srt--RangeAxis__srt--MinimumMember_z68gZQbmans4"&gt;8.5
                                            &lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;to
                                            &lt;span id="xdx_901_eus-gaap--SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_dtY_c20200101__20200630__srt--RangeAxis__srt--MaximumMember_zW5npx7wLpgg"&gt;10.0&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: White"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Expected
    dividend yield&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98F_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_pid_dpxL_c20210101__20210630_zIH0kzCyLy2g" style="font: 10pt Times New Roman, Times, Serif; text-align: right" title="Expected dividend yield::XDX::0"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1203"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_981_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_pid_dpxL_c20200101__20200630_zv50SIQiZlGk" style="font: 10pt Times New Roman, Times, Serif; text-align: right" title="Expected dividend yield::XDX::0"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1205"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p id="xdx_8A3_z2lHzkFiftZ1" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Expected
volatilities utilized in the model are based on historical volatility of the Company&#x2019;s stock price. The risk-free interest rate
is derived from values assigned to U.S. Treasury bonds with terms that approximate the expected option lives in effect at the time of
grant.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

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      decimals="INF"
      unitRef="USDPShares">3.10</us-gaap:ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice>
    <CLSN:SummaryOfStockOptionAndRestrictedStockAwardsTableTextBlock contextRef="From2021-01-01to2021-06-30">&lt;p id="xdx_897_ecustom--SummaryOfStockOptionAndRestrictedStockAwardsTableTextBlock_zdNvlcpS5MWa" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span id="xdx_8B5_zdwapitkW4Tb" style="font: 10pt Times New Roman, Times, Serif; display: none"&gt;Summary
of Stock Option Awards and Restricted Stock Grants&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Stock
    Options&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="6" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Restricted
    Stock Awards&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; font-weight: bold"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Weighted&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Average&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Options&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Outstanding&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Weighted&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Average&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Exercise&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Price&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Non-vested&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Restricted&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Stock&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Outstanding&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Weighted&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Average&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Grant&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Date&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Fair
                                            Value&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Contractual&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Terms
                                            of&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Equity&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Awards&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;(in
                                            years)&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 35%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Equity awards outstanding at January
    1, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_987_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_iS_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zs8NivCzWEJl" style="width: 9%; text-align: right" title="Number Outstanding, Outstanding, Beginning balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;4,624,725&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98E_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_iS_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zjNzVF9yzIq2" style="width: 9%; text-align: right" title="Weighted Average Exercise Price, Outstanding, Beginning balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2.77&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_984_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_iS_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_zqUlMKUubbcj" style="width: 9%; text-align: right" title="Number Outstanding, Non-vested stock awards, Outstanding, Beginning balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2,750&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_987_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_iS_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_z740gWcrLMA3" style="width: 9%; text-align: right" title="Weighted Average Grant Date Fair Value, Non-vested stock awards, Outstanding, Beginning balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;0.89&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 9%; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Equity awards granted&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_986_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_pdd" style="text-align: right" title="Number Outstanding, Options granted"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2,154,000&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_986_eus-gaap--ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_pdd" style="text-align: right" title="Weighted Average Exercise Price, Options granted"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2.18&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_987_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_pdd" style="text-align: right" title="Number Outstanding, Non-vested stock awards, Granted"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;7,000&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98E_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_pdd" style="text-align: right" title="Weighted Average Grant Date Fair Value, Non-vested stock awards, Granted"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;1.38&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Equity awards exercised or vested and issued&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_980_eus-gaap--StockIssuedDuringPeriodSharesStockOptionsExercised_iN_di_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zz9vwH6dwF9d" style="text-align: right" title="Number Outstanding, Options exercised or vested and issued"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;(7,500&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;)&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_985_eus-gaap--ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_pdd" style="text-align: right" title="Weighted Average Exercise Price, Options exercised or vested and issued"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;0.63&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_984_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_pdd" style="text-align: right" title="Number Outstanding, Non-vested stock awards, exercised or vested and issued"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1157"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98A_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_pdd" style="text-align: right" title="Weighted Average Grant Date Fair Value, Non-vested stock awards, exercised or vested and issued"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1159"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Equity awards forfeited,
    cancelled or expired&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_983_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod_iN_di_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zfFZt1TlTe2f" style="border-bottom: Black 1.5pt solid; text-align: right" title="Number Outstanding, Options canceled or expired"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;(92,646&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;)&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_981_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_pdd" style="padding-bottom: 1.5pt; text-align: right" title="Weighted Average Exercise Price, Options canceled or expired"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2.69&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98B_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_pdd" style="border-bottom: Black 1.5pt solid; text-align: right" title="Number Outstanding, Non-vested stock awards, Forfeited"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1165"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98E_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_pdd" style="padding-bottom: 1.5pt; text-align: right" title="Weighted Average Grant Date Fair Value, Non-vested stock awards, Forfeited"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1167"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Equity awards outstanding
    at June 30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98C_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_iE_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zZRQKzEajN1k" style="border-bottom: Black 2.5pt double; text-align: right" title="Number Outstanding, Outstanding, Ending balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;6,678,579&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98F_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_iE_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zoAmbc7LD97b" style="padding-bottom: 2.5pt; text-align: right" title="Weighted Average Exercise Price, Outstanding, Ending balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2.58&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98F_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_iE_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_z2MhcObQKuDf" style="border-bottom: Black 2.5pt double; text-align: right" title="Number Outstanding, Non-vested stock awards, Outstanding, Ending balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;9,750&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_985_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_iE_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_zkzFCAGm1tvg" style="padding-bottom: 2.5pt; text-align: right" title="Weighted Average Grant Date Fair Value, Non-vested stock awards, Outstanding, Ending balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;1.27&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;span id="xdx_905_eus-gaap--SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_dtY_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zbBH4fvhOS5i" style="font-family: Times New Roman, Times, Serif"&gt;8.0&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Aggregate intrinsic
    value of outstanding equity awards at June 30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_986_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_iE_pp0p0_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zgaOVGFesug1" style="border-bottom: Black 2.5pt double; text-align: right" title="Aggregate Intrinsic Value, Outstanding, Ending balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;12,145&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98C_eus-gaap--SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueOutstanding_iE_pp0p0_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--RestrictedStockMember_z7Sj2pid0O4k" style="border-bottom: Black 2.5pt double; text-align: right" title="Aggregate Intrinsic Value, Non-vested stock awards, Outstanding, Ending balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;12,383&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Equity awards exercisable
    at June 30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_980_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_iE_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zCGoAEnaXIjc" style="border-bottom: Black 2.5pt double; text-align: right" title="Number Outstanding, Exercisable, Ending balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;4,329,286&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98B_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice_iE_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zrk5BnhfHVWh" style="padding-bottom: 2.5pt; text-align: right" title="Weighted Average Exercise Price, Exercisable, Ending balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2.73&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;span id="xdx_90A_eus-gaap--SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1_dtY_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_ziiBCIpqp7bb" style="font-family: Times New Roman, Times, Serif"&gt;7.8&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Aggregate intrinsic
    value of equity awards exercisable at June 30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_984_eus-gaap--SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1_iE_pp0p0_c20210101__20210630__us-gaap--AwardTypeAxis__us-gaap--EmployeeStockOptionMember_zY55dMDQ9Goa" style="border-bottom: Black 2.5pt double; text-align: right" title="Aggregate Intrinsic Value, Exercisable, Ending balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;1,650&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

</CLSN:SummaryOfStockOptionAndRestrictedStockAwardsTableTextBlock>
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      contextRef="AsOf2020-12-31_us-gaap_EmployeeStockOptionMember"
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      unitRef="Shares">4624725</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice
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      unitRef="USDPShares">2.77</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber
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      unitRef="Shares">2750</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue
      contextRef="AsOf2020-12-31_us-gaap_RestrictedStockMember"
      decimals="INF"
      unitRef="USDPShares">0.89</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue>
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      unitRef="Shares">2154000</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod>
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      contextRef="From2021-01-012021-06-30_us-gaap_EmployeeStockOptionMember"
      decimals="INF"
      unitRef="USDPShares">2.18</us-gaap:ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod
      contextRef="From2021-01-012021-06-30_us-gaap_RestrictedStockMember"
      decimals="INF"
      unitRef="Shares">7000</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
      contextRef="From2021-01-012021-06-30_us-gaap_RestrictedStockMember"
      decimals="INF"
      unitRef="USDPShares">1.38</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue>
    <us-gaap:StockIssuedDuringPeriodSharesStockOptionsExercised
      contextRef="From2021-01-012021-06-30_us-gaap_EmployeeStockOptionMember"
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      contextRef="AsOf2021-06-30_us-gaap_EmployeeStockOptionMember"
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      unitRef="USDPShares">2.58</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber
      contextRef="AsOf2021-06-30_us-gaap_RestrictedStockMember"
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    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue
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      contextRef="AsOf2021-06-30_us-gaap_EmployeeStockOptionMember"
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    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice
      contextRef="AsOf2021-06-30_us-gaap_EmployeeStockOptionMember"
      decimals="INF"
      unitRef="USDPShares">2.73</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice>
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    <us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1
      contextRef="AsOf2021-06-30_us-gaap_EmployeeStockOptionMember"
      decimals="0"
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    <us-gaap:ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock contextRef="From2021-01-01to2021-06-30">&lt;p id="xdx_89C_eus-gaap--ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock_zvVrpPRBlNSd" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
fair values of stock options granted were estimated at the date of grant using the Black-Scholes option pricing model. The Black-Scholes
model was originally developed for use in estimating the fair value of traded options, which have different characteristics from Celsion&#x2019;s
stock options. The model is also sensitive to changes in assumptions, which can materially affect the fair value estimate. The Company
used the following assumptions for determining the fair value of options granted under the Black-Scholes option pricing model:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8B1_zAvmRlNBERij" style="display: none"&gt;Schedule
of Assumptions Used to Determine Fair Value of Options Granted&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"/&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: White"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td colspan="5" style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Six
                                            Months Ended June 30, &#160;&lt;/b&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: White"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;2021&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; font: bold 10pt Times New Roman, Times, Serif; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;2020&lt;/span&gt;&lt;/td&gt;&lt;td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 60%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Risk-free
    interest rate&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 2%"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 16%; text-align: right"&gt;&lt;span id="xdx_90C_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum_pid_dp_c20210101__20210630_zbHSZSVsxGng" style="font: 10pt Times New Roman, Times, Serif"&gt;1.56
                                            &lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;to &lt;span id="xdx_90C_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum_pid_dp_c20210101__20210630_z61dC6LUBpG7"&gt;1.74&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 2%"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 16%; text-align: right"&gt;&lt;span id="xdx_90D_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum_pid_dp_c20200101__20200630_zsBDu6znfba7" style="font: 10pt Times New Roman, Times, Serif"&gt;0.71
                                            &lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;to &lt;span id="xdx_903_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum_pid_dp_c20200101__20200630_z4h3tRgTmWW3"&gt;1.33&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: White"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Expected
    volatility&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span id="xdx_908_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMinimum_pid_dp_c20210101__20210630_zOviDMd7lCtf" style="font: 10pt Times New Roman, Times, Serif"&gt;106.8
                                            &lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;to &lt;span id="xdx_904_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum_pid_dp_c20210101__20210630_zY4Mod2WgDI"&gt;113.0&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span id="xdx_901_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMinimum_pid_dp_c20200101__20200630_zNHIZ28tcg1d" style="font: 10pt Times New Roman, Times, Serif"&gt;100.4
                                            &lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;to &lt;span id="xdx_904_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum_pid_dp_c20200101__20200630_zmTjM8Vk6KF7"&gt;104.2&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Expected
    life (in years)&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span id="xdx_90D_eus-gaap--SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_dtY_c20210101__20210630__srt--RangeAxis__srt--MinimumMember_zUnxBpAcWXsk" style="font: 10pt Times New Roman, Times, Serif"&gt;7.5
                                            &lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;to &lt;span id="xdx_904_eus-gaap--SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_dtY_c20210101__20210630__srt--RangeAxis__srt--MaximumMember_ziitPTyChS7f"&gt;10.0&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: right"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_903_eus-gaap--SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_dtY_c20200101__20200630__srt--RangeAxis__srt--MinimumMember_z68gZQbmans4"&gt;8.5
                                            &lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;to
                                            &lt;span id="xdx_901_eus-gaap--SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_dtY_c20200101__20200630__srt--RangeAxis__srt--MaximumMember_zW5npx7wLpgg"&gt;10.0&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: bottom; background-color: White"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Expected
    dividend yield&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98F_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_pid_dpxL_c20210101__20210630_zIH0kzCyLy2g" style="font: 10pt Times New Roman, Times, Serif; text-align: right" title="Expected dividend yield::XDX::0"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1203"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_981_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_pid_dpxL_c20200101__20200630_zv50SIQiZlGk" style="font: 10pt Times New Roman, Times, Serif; text-align: right" title="Expected dividend yield::XDX::0"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1205"&gt;-&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: left"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

</us-gaap:ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum
      contextRef="From2021-01-01to2021-06-30"
      decimals="INF"
      unitRef="Percentage">0.0156</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum
      contextRef="From2021-01-01to2021-06-30"
      decimals="INF"
      unitRef="Percentage">0.0174</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum
      contextRef="From2020-01-012020-06-30"
      decimals="INF"
      unitRef="Percentage">0.0071</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum
      contextRef="From2020-01-012020-06-30"
      decimals="INF"
      unitRef="Percentage">0.0133</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMinimum
      contextRef="From2021-01-01to2021-06-30"
      decimals="INF"
      unitRef="Percentage">1.068</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMinimum>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum
      contextRef="From2021-01-01to2021-06-30"
      decimals="INF"
      unitRef="Percentage">1.130</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum>
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      contextRef="From2020-01-012020-06-30"
      decimals="INF"
      unitRef="Percentage">1.004</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMinimum>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum
      contextRef="From2020-01-012020-06-30"
      decimals="INF"
      unitRef="Percentage">1.042</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum>
    <us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1 contextRef="From2021-01-012021-06-30_srt_MinimumMember">P7Y6M</us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1>
    <us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1 contextRef="From2021-01-012021-06-30_srt_MaximumMember">P10Y</us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1>
    <us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1 contextRef="From2020-01-012020-06-30_srt_MinimumMember">P8Y6M</us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1>
    <us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1 contextRef="From2020-01-012020-06-30_srt_MaximumMember">P10Y</us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1>
    <CLSN:EarnoutMilestoneLiabilityDisclosureTextBlock contextRef="From2021-01-01to2021-06-30">&lt;p id="xdx_801_ecustom--EarnoutMilestoneLiabilityDisclosureTextBlock_zWkAYpPd0my2" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
14. &lt;span id="xdx_820_zevo1lJWXTn"&gt;Earn-Out Milestone Liability&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
March 28, 2019, the Company and EGWU, Inc, entered into an amendment to its purchase agreement (&#x201c;Amended Asset Purchase Agreement&#x201d;),
whereby payment of the earnout milestone liability related to the Ovarian Cancer Indication of $&lt;span id="xdx_90F_ecustom--EarnoutMilestoneLiability1_iI_pn5n6_c20190328__us-gaap--TypeOfArrangementAxis__custom--AmendedAssetPurchaseAgreementMember__us-gaap--RelatedPartyTransactionAxis__custom--AchievingMilestoneWithInOneYearMember_zKFdi26YYdQf"&gt;12.4
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million had been modified. The Company has the
option to make the payment as follows:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 0.25in; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;a)&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;span id="xdx_903_ecustom--EarnoutMilestoneLiability1_iI_pn5n6_c20190328__us-gaap--TypeOfArrangementAxis__custom--AmendedAssetPurchaseAgreementMember__us-gaap--RelatedPartyTransactionAxis__custom--CertainBusinessDaysOfAchievingMilestoneMember_zsLTm1kmMUok"&gt;7.0
    &lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million in cash within 10 business days of
    achieving the milestone; or&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;b)&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;$&lt;span id="xdx_901_ecustom--EarnoutMilestoneLiability1_iI_pn5n6_c20190328__us-gaap--TypeOfArrangementAxis__custom--AmendedAssetPurchaseAgreementMember_zWYkwwuaJn8d"&gt;12.4
    &lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million in cash, common stock of the Company,
    or a combination of either, within one year of achieving the milestone.&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;
&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;As
of June 30, 2021, March 31, 2021, and December 31, 2020, the Company fair valued the earn-out milestone liability at $&lt;span id="xdx_907_eus-gaap--BusinessCombinationConsiderationTransferredLiabilitiesIncurred_pn5n6_c20210101__20210630__us-gaap--BusinessAcquisitionAxis__custom--EGWCMember__us-gaap--TypeOfArrangementAxis__custom--FairValueEarnoutMilestoneLiabilityMember_zjvRVWZhGx1c"&gt;7.1
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million, $&lt;span id="xdx_909_eus-gaap--BusinessCombinationConsiderationTransferredLiabilitiesIncurred_pn5n6_c20210101__20210331__us-gaap--BusinessAcquisitionAxis__custom--EGWCMember__us-gaap--TypeOfArrangementAxis__custom--FairValueEarnoutMilestoneLiabilityMember_z6g6Qd6I8Dqc"&gt;7.2
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million and $&lt;span id="xdx_906_eus-gaap--BusinessCombinationConsiderationTransferredLiabilitiesIncurred_pn5n6_c20200101__20201231__us-gaap--BusinessAcquisitionAxis__custom--EGWCMember__us-gaap--TypeOfArrangementAxis__custom--FairValueEarnoutMilestoneLiabilityMember_zfxlEFu7gUWe"&gt;7.0
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million, respectively, and recognized a non-cash
benefit of $&lt;span id="xdx_900_ecustom--NoncashChargeOnEarnoutMilestoneLiability_pn5n6_c20210401__20210630__us-gaap--BusinessAcquisitionAxis__custom--EGWCMember_zkTm03nK4Z6c"&gt;0.1
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million for the three-months ended June 30, 2021
and a non-cash charge of $&lt;span id="xdx_909_ecustom--NoncashChargeOnEarnoutMilestoneLiability_pn5n6_c20210101__20210630__us-gaap--BusinessAcquisitionAxis__custom--EGWCMember_zMn6JPDjG6Ea"&gt;0.1
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million for the six-months ended June 30, 2021.
&lt;span id="xdx_90C_ecustom--EarnoutPaymentOptionsDescription_c20210101__20210630__us-gaap--BusinessAcquisitionAxis__custom--EGWCMember"&gt;In
assessing the earnout milestone liability at June 30, 2021 and March 31, 2021, the Company fair valued each of the two payment options
per the Amended Asset Purchase Agreement and weighted them at 50% / 50% probability for the $7.0 million and the $12.4 million payments,
respectively.&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;As
of June 30, 2020, March 31, 2020, and December 31, 2019, the Company fair valued the earn-out milestone liability at $&lt;span id="xdx_903_eus-gaap--BusinessCombinationConsiderationTransferredLiabilitiesIncurred_pn5n6_c20200101__20200630__us-gaap--BusinessAcquisitionAxis__custom--EGWCMember__us-gaap--TypeOfArrangementAxis__custom--FairValueEarnoutMilestoneLiabilityMember_zdUaHYWPIH78"&gt;6.0
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million, $&lt;span id="xdx_90F_eus-gaap--BusinessCombinationConsiderationTransferredLiabilitiesIncurred_pn5n6_c20200101__20200331__us-gaap--BusinessAcquisitionAxis__custom--EGWCMember__us-gaap--TypeOfArrangementAxis__custom--FairValueEarnoutMilestoneLiabilityMember_ziEPznTBpyw6"&gt;5.8
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million,&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;
and $&lt;span id="xdx_907_eus-gaap--BusinessCombinationConsiderationTransferredLiabilitiesIncurred_pn5n6_c20190101__20191231__us-gaap--BusinessAcquisitionAxis__custom--EGWCMember__us-gaap--TypeOfArrangementAxis__custom--FairValueEarnoutMilestoneLiabilityMember_zsBFzoSykRF5"&gt;5.7
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million, respectively and recognized a non-cash
charge of $&lt;span id="xdx_905_ecustom--NoncashChargeOnEarnoutMilestoneLiability_pn5n6_c20200401__20200630__us-gaap--BusinessAcquisitionAxis__custom--EGWCMember_zHV7NOomI5m"&gt;0.2
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;and $&lt;span id="xdx_903_ecustom--NoncashChargeOnEarnoutMilestoneLiability_pn5n6_c20200101__20200630__us-gaap--BusinessAcquisitionAxis__custom--EGWCMember_zmg9dSrazTr3"&gt;0.3
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million for the three-month and six-month periods
ended June 30, 2020, respectively. &lt;span id="xdx_90A_ecustom--EarnoutPaymentOptionsDescription_c20200101__20200630__us-gaap--BusinessAcquisitionAxis__custom--EGWCMember"&gt;In
assessing the earnout milestone liability at June 30, 2020 and March 31, 2020, the Company fair valued each of the two payment options
per the Amended Asset Purchase Agreement and weighted them at 80% / 20% probability for the $7.0 million and the $12.4 million
payments, respectively.&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p id="xdx_896_ecustom--ScheduleOfChangesInEarnOutMilestoneLiabilitiesTableTextBlock_zg2vwNiSH1K5" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
following is a summary of the changes in the earn-out milestone liability for the six-month period ended June 30, 2021:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8B2_z8jvCwx4n2j5" style="display: none"&gt;Schedule
of Changes in Earn-out Milestone Liability&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="display: none; vertical-align: bottom; background-color: White"&gt;
    &lt;td style="display: none; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="display: none"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="display: none; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="display: none; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="display: none; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 80%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Balance at January 1, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_981_ecustom--EarnoutMilestoneLiability_iS_pp0p0_c20210101__20210630_zfgHFwac9LC5" style="width: 16%; text-align: right" title="Earn-out liabilities, beginning balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;(7,018,000&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;)&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Non-cash loss from the
    change in fair value&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98A_ecustom--GainLossFromChangeInFairValueOfEarnOutMilestoneLiability_c20210101__20210630_pp0p0" style="border-bottom: Black 1.5pt solid; text-align: right" title="Non-cash gain loss from the adjustment for the change in fair value"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;(70,000&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;)&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Balance at June 30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98A_ecustom--EarnoutMilestoneLiability_iE_pp0p0_c20210101__20210630_zF3silNymLdi" style="border-bottom: Black 2.5pt double; text-align: right" title="Earn-out liabilities, ending balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;(7,088,000&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;)&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p id="xdx_8A1_zh5NamNYDdCg" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p id="xdx_898_ecustom--ScheduleOfRiskadjustmentAssessmentTableTextBlock_zO1NEdKx5kH" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
following is a schedule of the Company&#x2019;s risk-adjustment assessment of each milestone:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8BD_zLRJ6Thwwb7i" style="display: none"&gt;Schedule
of Risk Adjustment Assessment&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Date&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Risk-adjustment
                                            Assessment&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;of
                                            Achieving Each Milestone&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Discount
    Rate&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Estimated
                                            Time&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;to
                                            Achieve&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: justify"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 44%; text-align: justify"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;June 30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98C_ecustom--RiskadjustmentAssessmentOfAchievingMilestone_pid_dp_c20210101__20210630_ztRZNKc1f1I" style="width: 13%; text-align: right" title="Risk-adjustment Assessment of achieving each Milestone"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;80&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_983_ecustom--DiscountRatesOnMileStoneLiabilities_pid_dp_c20210101__20210630_ztDD9dRCkHqj" style="width: 13%; text-align: right" title="Discount Rate"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;9&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 20%; text-align: right"&gt;&lt;span id="xdx_90B_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20210101__20210630__srt--RangeAxis__srt--MinimumMember_ztCH7vWA4Fdg" style="font-family: Times New Roman, Times, Serif"&gt;0.42
    &lt;/span&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;to &lt;span id="xdx_906_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20210101__20210630__srt--RangeAxis__srt--MaximumMember_zevrFDAxNcCi"&gt;1.42
    &lt;/span&gt;&lt;/span&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;years&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: justify"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;March 31, 2021&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98A_ecustom--RiskadjustmentAssessmentOfAchievingMilestone_pid_dp_c20210101__20210331_zY1Iv8PYEvyc" style="text-align: right" title="Risk-adjustment Assessment of achieving each Milestone"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;80&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98D_ecustom--DiscountRatesOnMileStoneLiabilities_pid_dp_c20210101__20210331_zvh5TKmdNpp1" style="text-align: right" title="Discount Rate"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;9&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: right"&gt;&lt;span id="xdx_907_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20210101__20210331__srt--RangeAxis__srt--MinimumMember_z2v5sX2fdw75" style="font-family: Times New Roman, Times, Serif"&gt;0.29
    &lt;/span&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;to &lt;span id="xdx_901_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20210101__20210331__srt--RangeAxis__srt--MaximumMember_zv6kYZh3KWK1"&gt;1.29
    &lt;/span&gt;&lt;/span&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;years&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: justify"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;December 31, 2020&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_982_ecustom--RiskadjustmentAssessmentOfAchievingMilestone_pid_dp_c20200101__20201231_zmiycbmZaiel" style="text-align: right" title="Risk-adjustment Assessment of achieving each Milestone"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;80&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_980_ecustom--DiscountRatesOnMileStoneLiabilities_pid_dp_c20200101__20201231_zuXh5ODTXFGg" style="text-align: right" title="Discount Rate"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;9&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: right"&gt;&lt;span id="xdx_90C_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20200101__20201231__srt--RangeAxis__srt--MinimumMember_zmbUCcKbn2fb" style="font-family: Times New Roman, Times, Serif"&gt;0.54
    &lt;/span&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;to &lt;span id="xdx_902_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20200101__20201231__srt--RangeAxis__srt--MaximumMember_zmJM2FABs6Vf"&gt;1.54
    &lt;/span&gt;&lt;/span&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;years&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: justify"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: justify"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;June 30, 2020&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_988_ecustom--RiskadjustmentAssessmentOfAchievingMilestone_pid_dp_c20200101__20200630_zGc1e3DNHwwj" style="text-align: right" title="Risk-adjustment Assessment of achieving each Milestone"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;80&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_983_ecustom--DiscountRatesOnMileStoneLiabilities_pid_dp_c20200101__20200630_zX0YcalEWrh7" style="text-align: right" title="Discount Rate"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;9&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: right"&gt;&lt;span id="xdx_90C_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20200101__20200630__srt--RangeAxis__srt--MinimumMember_zt7tUOXUIJAf" style="font-family: Times New Roman, Times, Serif"&gt;0.54
    &lt;/span&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;to &lt;span id="xdx_90C_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20200101__20200630__srt--RangeAxis__srt--MaximumMember_zl8FIdnX8JR"&gt;1.54
    &lt;/span&gt;&lt;/span&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;years&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: justify"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;March 31, 2020&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98E_ecustom--RiskadjustmentAssessmentOfAchievingMilestone_pid_dp_c20200101__20200331_zM3RagkkzXQh" style="text-align: right" title="Risk-adjustment Assessment of achieving each Milestone"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;80&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98D_ecustom--DiscountRatesOnMileStoneLiabilities_pid_dp_c20200101__20200331_zSl9XdEFA8i8" style="text-align: right" title="Discount Rate"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;9&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: right"&gt;&lt;span id="xdx_903_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20200101__20200331__srt--RangeAxis__srt--MinimumMember_zTxJcY5cbtB8" style="font-family: Times New Roman, Times, Serif"&gt;1.04
    &lt;/span&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;to &lt;span id="xdx_904_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20200101__20200331__srt--RangeAxis__srt--MaximumMember_zW6qWcQqJyWj"&gt;2.04
    &lt;/span&gt;&lt;/span&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;years&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: justify"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;December 31, 2019&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98F_ecustom--RiskadjustmentAssessmentOfAchievingMilestone_pid_dp_c20190101__20191231_z5cHHwdO0F3a" style="text-align: right" title="Risk-adjustment Assessment of achieving each Milestone"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;80&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98D_ecustom--DiscountRatesOnMileStoneLiabilities_pid_dp_c20190101__20191231_zD0krJglEmxi" style="text-align: right" title="Discount Rate"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;9&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: right"&gt;&lt;span id="xdx_909_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20190101__20191231__srt--RangeAxis__srt--MinimumMember_zytePsubsX1c" style="font-family: Times New Roman, Times, Serif"&gt;1.12
    &lt;/span&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;to &lt;span id="xdx_908_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20190101__20191231__srt--RangeAxis__srt--MaximumMember_z1S7SwBwmHdi"&gt;2.12
    &lt;/span&gt;&lt;/span&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;years&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p id="xdx_8A4_zqKPVn7iWL7c" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;&#160;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;




&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;&#160;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

</CLSN:EarnoutMilestoneLiabilityDisclosureTextBlock>
    <CLSN:EarnoutMilestoneLiability1
      contextRef="AsOf2019-03-28_custom_AmendedAssetPurchaseAgreementMember_custom_AchievingMilestoneWithInOneYearMember"
      decimals="-5"
      unitRef="USD">12400000</CLSN:EarnoutMilestoneLiability1>
    <CLSN:EarnoutMilestoneLiability1
      contextRef="AsOf2019-03-28_custom_AmendedAssetPurchaseAgreementMember_custom_CertainBusinessDaysOfAchievingMilestoneMember"
      decimals="-5"
      unitRef="USD">7000000.0</CLSN:EarnoutMilestoneLiability1>
    <CLSN:EarnoutMilestoneLiability1
      contextRef="AsOf2019-03-28_custom_AmendedAssetPurchaseAgreementMember"
      decimals="-5"
      unitRef="USD">12400000</CLSN:EarnoutMilestoneLiability1>
    <us-gaap:BusinessCombinationConsiderationTransferredLiabilitiesIncurred
      contextRef="From2021-01-012021-06-30_custom_EGWCMember_custom_FairValueEarnoutMilestoneLiabilityMember"
      decimals="-5"
      unitRef="USD">7100000</us-gaap:BusinessCombinationConsiderationTransferredLiabilitiesIncurred>
    <us-gaap:BusinessCombinationConsiderationTransferredLiabilitiesIncurred
      contextRef="From2021-01-012021-03-31_custom_EGWCMember_custom_FairValueEarnoutMilestoneLiabilityMember"
      decimals="-5"
      unitRef="USD">7200000</us-gaap:BusinessCombinationConsiderationTransferredLiabilitiesIncurred>
    <us-gaap:BusinessCombinationConsiderationTransferredLiabilitiesIncurred
      contextRef="From2020-01-012020-12-31_custom_EGWCMember_custom_FairValueEarnoutMilestoneLiabilityMember"
      decimals="-5"
      unitRef="USD">7000000.0</us-gaap:BusinessCombinationConsiderationTransferredLiabilitiesIncurred>
    <CLSN:NoncashChargeOnEarnoutMilestoneLiability
      contextRef="From2021-04-012021-06-30_custom_EGWCMember"
      decimals="-5"
      unitRef="USD">100000</CLSN:NoncashChargeOnEarnoutMilestoneLiability>
    <CLSN:NoncashChargeOnEarnoutMilestoneLiability
      contextRef="From2021-01-012021-06-30_custom_EGWCMember"
      decimals="-5"
      unitRef="USD">100000</CLSN:NoncashChargeOnEarnoutMilestoneLiability>
    <CLSN:EarnoutPaymentOptionsDescription contextRef="From2021-01-012021-06-30_custom_EGWCMember">In
assessing the earnout milestone liability at June 30, 2021 and March 31, 2021, the Company fair valued each of the two payment options
per the Amended Asset Purchase Agreement and weighted them at 50% / 50% probability for the $7.0 million and the $12.4 million payments,
respectively.</CLSN:EarnoutPaymentOptionsDescription>
    <us-gaap:BusinessCombinationConsiderationTransferredLiabilitiesIncurred
      contextRef="From2020-01-012020-06-30_custom_EGWCMember_custom_FairValueEarnoutMilestoneLiabilityMember"
      decimals="-5"
      unitRef="USD">6000000.0</us-gaap:BusinessCombinationConsiderationTransferredLiabilitiesIncurred>
    <us-gaap:BusinessCombinationConsiderationTransferredLiabilitiesIncurred
      contextRef="From2020-01-012020-03-31_custom_EGWCMember_custom_FairValueEarnoutMilestoneLiabilityMember"
      decimals="-5"
      unitRef="USD">5800000</us-gaap:BusinessCombinationConsiderationTransferredLiabilitiesIncurred>
    <us-gaap:BusinessCombinationConsiderationTransferredLiabilitiesIncurred
      contextRef="From2019-01-012019-12-31_custom_EGWCMember_custom_FairValueEarnoutMilestoneLiabilityMember"
      decimals="-5"
      unitRef="USD">5700000</us-gaap:BusinessCombinationConsiderationTransferredLiabilitiesIncurred>
    <CLSN:NoncashChargeOnEarnoutMilestoneLiability
      contextRef="From2020-04-012020-06-30_custom_EGWCMember"
      decimals="-5"
      unitRef="USD">200000</CLSN:NoncashChargeOnEarnoutMilestoneLiability>
    <CLSN:NoncashChargeOnEarnoutMilestoneLiability
      contextRef="From2020-01-012020-06-30_custom_EGWCMember"
      decimals="-5"
      unitRef="USD">300000</CLSN:NoncashChargeOnEarnoutMilestoneLiability>
    <CLSN:EarnoutPaymentOptionsDescription contextRef="From2020-01-012020-06-30_custom_EGWCMember">In
assessing the earnout milestone liability at June 30, 2020 and March 31, 2020, the Company fair valued each of the two payment options
per the Amended Asset Purchase Agreement and weighted them at 80% / 20% probability for the $7.0 million and the $12.4 million
payments, respectively.</CLSN:EarnoutPaymentOptionsDescription>
    <CLSN:ScheduleOfChangesInEarnOutMilestoneLiabilitiesTableTextBlock contextRef="From2021-01-01to2021-06-30">&lt;p id="xdx_896_ecustom--ScheduleOfChangesInEarnOutMilestoneLiabilitiesTableTextBlock_zg2vwNiSH1K5" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
following is a summary of the changes in the earn-out milestone liability for the six-month period ended June 30, 2021:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8B2_z8jvCwx4n2j5" style="display: none"&gt;Schedule
of Changes in Earn-out Milestone Liability&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="display: none; vertical-align: bottom; background-color: White"&gt;
    &lt;td style="display: none; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="display: none"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="display: none; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="display: none; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="display: none; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 80%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Balance at January 1, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_981_ecustom--EarnoutMilestoneLiability_iS_pp0p0_c20210101__20210630_zfgHFwac9LC5" style="width: 16%; text-align: right" title="Earn-out liabilities, beginning balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;(7,018,000&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;)&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Non-cash loss from the
    change in fair value&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98A_ecustom--GainLossFromChangeInFairValueOfEarnOutMilestoneLiability_c20210101__20210630_pp0p0" style="border-bottom: Black 1.5pt solid; text-align: right" title="Non-cash gain loss from the adjustment for the change in fair value"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;(70,000&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;)&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Balance at June 30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98A_ecustom--EarnoutMilestoneLiability_iE_pp0p0_c20210101__20210630_zF3silNymLdi" style="border-bottom: Black 2.5pt double; text-align: right" title="Earn-out liabilities, ending balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;(7,088,000&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;)&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

</CLSN:ScheduleOfChangesInEarnOutMilestoneLiabilitiesTableTextBlock>
    <CLSN:EarnoutMilestoneLiability contextRef="AsOf2020-12-31" decimals="0" unitRef="USD">-7018000</CLSN:EarnoutMilestoneLiability>
    <CLSN:GainLossFromChangeInFairValueOfEarnOutMilestoneLiability
      contextRef="From2021-01-01to2021-06-30"
      decimals="0"
      unitRef="USD">-70000</CLSN:GainLossFromChangeInFairValueOfEarnOutMilestoneLiability>
    <CLSN:EarnoutMilestoneLiability contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">-7088000</CLSN:EarnoutMilestoneLiability>
    <CLSN:ScheduleOfRiskadjustmentAssessmentTableTextBlock contextRef="From2021-01-01to2021-06-30">&lt;p id="xdx_898_ecustom--ScheduleOfRiskadjustmentAssessmentTableTextBlock_zO1NEdKx5kH" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
following is a schedule of the Company&#x2019;s risk-adjustment assessment of each milestone:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8BD_zLRJ6Thwwb7i" style="display: none"&gt;Schedule
of Risk Adjustment Assessment&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Date&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Risk-adjustment
                                            Assessment&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;of
                                            Achieving Each Milestone&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Discount
    Rate&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Estimated
                                            Time&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;to
                                            Achieve&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: justify"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: center"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 44%; text-align: justify"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;June 30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98C_ecustom--RiskadjustmentAssessmentOfAchievingMilestone_pid_dp_c20210101__20210630_ztRZNKc1f1I" style="width: 13%; text-align: right" title="Risk-adjustment Assessment of achieving each Milestone"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;80&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_983_ecustom--DiscountRatesOnMileStoneLiabilities_pid_dp_c20210101__20210630_ztDD9dRCkHqj" style="width: 13%; text-align: right" title="Discount Rate"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;9&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 20%; text-align: right"&gt;&lt;span id="xdx_90B_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20210101__20210630__srt--RangeAxis__srt--MinimumMember_ztCH7vWA4Fdg" style="font-family: Times New Roman, Times, Serif"&gt;0.42
    &lt;/span&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;to &lt;span id="xdx_906_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20210101__20210630__srt--RangeAxis__srt--MaximumMember_zevrFDAxNcCi"&gt;1.42
    &lt;/span&gt;&lt;/span&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;years&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: justify"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;March 31, 2021&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98A_ecustom--RiskadjustmentAssessmentOfAchievingMilestone_pid_dp_c20210101__20210331_zY1Iv8PYEvyc" style="text-align: right" title="Risk-adjustment Assessment of achieving each Milestone"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;80&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98D_ecustom--DiscountRatesOnMileStoneLiabilities_pid_dp_c20210101__20210331_zvh5TKmdNpp1" style="text-align: right" title="Discount Rate"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;9&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: right"&gt;&lt;span id="xdx_907_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20210101__20210331__srt--RangeAxis__srt--MinimumMember_z2v5sX2fdw75" style="font-family: Times New Roman, Times, Serif"&gt;0.29
    &lt;/span&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;to &lt;span id="xdx_901_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20210101__20210331__srt--RangeAxis__srt--MaximumMember_zv6kYZh3KWK1"&gt;1.29
    &lt;/span&gt;&lt;/span&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;years&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: justify"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;December 31, 2020&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_982_ecustom--RiskadjustmentAssessmentOfAchievingMilestone_pid_dp_c20200101__20201231_zmiycbmZaiel" style="text-align: right" title="Risk-adjustment Assessment of achieving each Milestone"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;80&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_980_ecustom--DiscountRatesOnMileStoneLiabilities_pid_dp_c20200101__20201231_zuXh5ODTXFGg" style="text-align: right" title="Discount Rate"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;9&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: right"&gt;&lt;span id="xdx_90C_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20200101__20201231__srt--RangeAxis__srt--MinimumMember_zmbUCcKbn2fb" style="font-family: Times New Roman, Times, Serif"&gt;0.54
    &lt;/span&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;to &lt;span id="xdx_902_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20200101__20201231__srt--RangeAxis__srt--MaximumMember_zmJM2FABs6Vf"&gt;1.54
    &lt;/span&gt;&lt;/span&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;years&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: justify"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: justify"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;June 30, 2020&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_988_ecustom--RiskadjustmentAssessmentOfAchievingMilestone_pid_dp_c20200101__20200630_zGc1e3DNHwwj" style="text-align: right" title="Risk-adjustment Assessment of achieving each Milestone"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;80&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_983_ecustom--DiscountRatesOnMileStoneLiabilities_pid_dp_c20200101__20200630_zX0YcalEWrh7" style="text-align: right" title="Discount Rate"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;9&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: right"&gt;&lt;span id="xdx_90C_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20200101__20200630__srt--RangeAxis__srt--MinimumMember_zt7tUOXUIJAf" style="font-family: Times New Roman, Times, Serif"&gt;0.54
    &lt;/span&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;to &lt;span id="xdx_90C_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20200101__20200630__srt--RangeAxis__srt--MaximumMember_zl8FIdnX8JR"&gt;1.54
    &lt;/span&gt;&lt;/span&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;years&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: justify"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;March 31, 2020&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98E_ecustom--RiskadjustmentAssessmentOfAchievingMilestone_pid_dp_c20200101__20200331_zM3RagkkzXQh" style="text-align: right" title="Risk-adjustment Assessment of achieving each Milestone"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;80&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98D_ecustom--DiscountRatesOnMileStoneLiabilities_pid_dp_c20200101__20200331_zSl9XdEFA8i8" style="text-align: right" title="Discount Rate"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;9&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: right"&gt;&lt;span id="xdx_903_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20200101__20200331__srt--RangeAxis__srt--MinimumMember_zTxJcY5cbtB8" style="font-family: Times New Roman, Times, Serif"&gt;1.04
    &lt;/span&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;to &lt;span id="xdx_904_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20200101__20200331__srt--RangeAxis__srt--MaximumMember_zW6qWcQqJyWj"&gt;2.04
    &lt;/span&gt;&lt;/span&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;years&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: justify"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;December 31, 2019&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98F_ecustom--RiskadjustmentAssessmentOfAchievingMilestone_pid_dp_c20190101__20191231_z5cHHwdO0F3a" style="text-align: right" title="Risk-adjustment Assessment of achieving each Milestone"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;80&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98D_ecustom--DiscountRatesOnMileStoneLiabilities_pid_dp_c20190101__20191231_zD0krJglEmxi" style="text-align: right" title="Discount Rate"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;9&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: right"&gt;&lt;span id="xdx_909_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20190101__20191231__srt--RangeAxis__srt--MinimumMember_zytePsubsX1c" style="font-family: Times New Roman, Times, Serif"&gt;1.12
    &lt;/span&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;to &lt;span id="xdx_908_ecustom--EstimatedTimeToAchieveMileStone_dtY_c20190101__20191231__srt--RangeAxis__srt--MaximumMember_z1S7SwBwmHdi"&gt;2.12
    &lt;/span&gt;&lt;/span&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;years&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

</CLSN:ScheduleOfRiskadjustmentAssessmentTableTextBlock>
    <CLSN:RiskadjustmentAssessmentOfAchievingMilestone
      contextRef="From2021-01-01to2021-06-30"
      decimals="INF"
      unitRef="Percentage">0.80</CLSN:RiskadjustmentAssessmentOfAchievingMilestone>
    <CLSN:DiscountRatesOnMileStoneLiabilities
      contextRef="From2021-01-01to2021-06-30"
      decimals="INF"
      unitRef="Percentage">0.09</CLSN:DiscountRatesOnMileStoneLiabilities>
    <CLSN:EstimatedTimeToAchieveMileStone contextRef="From2021-01-012021-06-30_srt_MinimumMember">P0Y5M1D</CLSN:EstimatedTimeToAchieveMileStone>
    <CLSN:EstimatedTimeToAchieveMileStone contextRef="From2021-01-012021-06-30_srt_MaximumMember">P1Y5M1D</CLSN:EstimatedTimeToAchieveMileStone>
    <CLSN:RiskadjustmentAssessmentOfAchievingMilestone
      contextRef="From2021-01-012021-03-31"
      decimals="INF"
      unitRef="Percentage">0.80</CLSN:RiskadjustmentAssessmentOfAchievingMilestone>
    <CLSN:DiscountRatesOnMileStoneLiabilities
      contextRef="From2021-01-012021-03-31"
      decimals="INF"
      unitRef="Percentage">0.09</CLSN:DiscountRatesOnMileStoneLiabilities>
    <CLSN:EstimatedTimeToAchieveMileStone contextRef="From2021-01-012021-03-31_srt_MinimumMember">P0Y3M14D</CLSN:EstimatedTimeToAchieveMileStone>
    <CLSN:EstimatedTimeToAchieveMileStone contextRef="From2021-01-012021-03-31_srt_MaximumMember">P1Y3M14D</CLSN:EstimatedTimeToAchieveMileStone>
    <CLSN:RiskadjustmentAssessmentOfAchievingMilestone
      contextRef="From2020-01-012020-12-31"
      decimals="INF"
      unitRef="Percentage">0.80</CLSN:RiskadjustmentAssessmentOfAchievingMilestone>
    <CLSN:DiscountRatesOnMileStoneLiabilities
      contextRef="From2020-01-012020-12-31"
      decimals="INF"
      unitRef="Percentage">0.09</CLSN:DiscountRatesOnMileStoneLiabilities>
    <CLSN:EstimatedTimeToAchieveMileStone contextRef="From2020-01-012020-12-31_srt_MinimumMember">P0Y6M14D</CLSN:EstimatedTimeToAchieveMileStone>
    <CLSN:EstimatedTimeToAchieveMileStone contextRef="From2020-01-012020-12-31_srt_MaximumMember">P1Y6M14D</CLSN:EstimatedTimeToAchieveMileStone>
    <CLSN:RiskadjustmentAssessmentOfAchievingMilestone
      contextRef="From2020-01-012020-06-30"
      decimals="INF"
      unitRef="Percentage">0.80</CLSN:RiskadjustmentAssessmentOfAchievingMilestone>
    <CLSN:DiscountRatesOnMileStoneLiabilities
      contextRef="From2020-01-012020-06-30"
      decimals="INF"
      unitRef="Percentage">0.09</CLSN:DiscountRatesOnMileStoneLiabilities>
    <CLSN:EstimatedTimeToAchieveMileStone contextRef="From2020-01-012020-06-30_srt_MinimumMember">P0Y6M14D</CLSN:EstimatedTimeToAchieveMileStone>
    <CLSN:EstimatedTimeToAchieveMileStone contextRef="From2020-01-012020-06-30_srt_MaximumMember">P1Y6M14D</CLSN:EstimatedTimeToAchieveMileStone>
    <CLSN:RiskadjustmentAssessmentOfAchievingMilestone
      contextRef="From2020-01-012020-03-31"
      decimals="INF"
      unitRef="Percentage">0.80</CLSN:RiskadjustmentAssessmentOfAchievingMilestone>
    <CLSN:DiscountRatesOnMileStoneLiabilities
      contextRef="From2020-01-012020-03-31"
      decimals="INF"
      unitRef="Percentage">0.09</CLSN:DiscountRatesOnMileStoneLiabilities>
    <CLSN:EstimatedTimeToAchieveMileStone contextRef="From2020-01-012020-03-31_srt_MinimumMember">P1Y14D</CLSN:EstimatedTimeToAchieveMileStone>
    <CLSN:EstimatedTimeToAchieveMileStone contextRef="From2020-01-012020-03-31_srt_MaximumMember">P2Y14D</CLSN:EstimatedTimeToAchieveMileStone>
    <CLSN:RiskadjustmentAssessmentOfAchievingMilestone
      contextRef="From2019-01-012019-12-31"
      decimals="INF"
      unitRef="Percentage">0.80</CLSN:RiskadjustmentAssessmentOfAchievingMilestone>
    <CLSN:DiscountRatesOnMileStoneLiabilities
      contextRef="From2019-01-012019-12-31"
      decimals="INF"
      unitRef="Percentage">0.09</CLSN:DiscountRatesOnMileStoneLiabilities>
    <CLSN:EstimatedTimeToAchieveMileStone contextRef="From2019-01-012019-12-31_srt_MinimumMember">P1Y1M13D</CLSN:EstimatedTimeToAchieveMileStone>
    <CLSN:EstimatedTimeToAchieveMileStone contextRef="From2019-01-012019-12-31_srt_MaximumMember">P2Y1M13D</CLSN:EstimatedTimeToAchieveMileStone>
    <CLSN:WarrantsTextBlock contextRef="From2021-01-01to2021-06-30">&lt;p id="xdx_80F_ecustom--WarrantsTextBlock_zf8qffPJ69p5" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
15. &lt;span id="xdx_820_zsC0SEq00lV8"&gt;Warrants&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p id="xdx_89A_eus-gaap--ScheduleOfStockholdersEquityNoteWarrantsOrRightsTextBlock_zyLOReG12MB1" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Following
is a summary of all warrant activity for the six months ended June 30, 2021:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8B5_zuNPNjGPNfbh" style="display: none"&gt;Summary
of Warrant Activity&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="border-bottom: Black 1.5pt solid"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Warrants&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Number
                                            of&lt;br/&gt; Warrants&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Issued&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Weighted&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Average&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Exercise
                                            Price&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 60%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Warrants outstanding at December 31, 2020&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_981_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber_iS_c20210101__20210630_zAhiFozzRZib" style="width: 16%; text-align: right" title="Number of Warrants Issued, Warrants outstanding, Beginning balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;3,853,566&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_989_ecustom--ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingWeightedAverageExercisePrice_iS_c20210101__20210630_zqVVyHompmr8" style="width: 16%; text-align: right" title="Weighted Average Exercise Price, Warrants outstanding, Beginning balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;1.35&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Warrants exercised during the six
    months ended June 30, 2021 (see Note 12)&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98F_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExercised_iN_di_c20210101__20210630_zHPeBD6O7QY5" style="border-bottom: Black 1.5pt solid; text-align: right" title="Number of Warrants Issued, Warrants exercised"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;(1,216,667&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;)&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_988_ecustom--ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExerciseInPeriodWeightedAverageExercisePrice_c20210101__20210630_pdd" style="padding-bottom: 1.5pt; text-align: right" title="Weighted Average Exercise Price, Warrants exercised"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;1.24&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Warrants outstanding at June 30,
    2021&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98A_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber_iE_c20210101__20210630_zBZnYIt9d2i2" style="border-bottom: Black 2.5pt double; text-align: right" title="Number of Warrants Issued, Warrants outstanding, Ending balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2,636,899&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98B_ecustom--ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingWeightedAverageExercisePrice_iE_c20210101__20210630_zHc7RRbT6gP6" style="padding-bottom: 2.5pt; text-align: right" title="Weighted Average Exercise Price, Warrants outstanding, Ending balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;1.40&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Aggregate intrinsic value of outstanding
    warrants at June 30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98A_ecustom--ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionsOutstandingIntrinsicValue_iE_pp0p0_c20210101__20210630_zvgKs6wzw12k" style="border-bottom: Black 2.5pt double; text-align: right" title="Aggregate intrinsic value of outstanding warrants"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;159,857&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Weighted average remaining contractual terms at June 30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span id="xdx_90E_ecustom--SharebasedCompensationArrangementBySharebasedPaymentAwardNonOptionsOutstandingWeightedAverageRemainingContractualTerm2_dtY_c20210101__20210630_ztBClSvcASZk" style="font: 10pt Times New Roman, Times, Serif"&gt;4.6
                                            &lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;years&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p id="xdx_8AC_zR7J2T3aIpdh" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

</CLSN:WarrantsTextBlock>
    <us-gaap:ScheduleOfStockholdersEquityNoteWarrantsOrRightsTextBlock contextRef="From2021-01-01to2021-06-30">&lt;p id="xdx_89A_eus-gaap--ScheduleOfStockholdersEquityNoteWarrantsOrRightsTextBlock_zyLOReG12MB1" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Following
is a summary of all warrant activity for the six months ended June 30, 2021:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8B5_zuNPNjGPNfbh" style="display: none"&gt;Summary
of Warrant Activity&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="border-bottom: Black 1.5pt solid"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Warrants&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Number
                                            of&lt;br/&gt; Warrants&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Issued&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Weighted&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Average&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Exercise
                                            Price&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 60%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Warrants outstanding at December 31, 2020&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_981_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber_iS_c20210101__20210630_zAhiFozzRZib" style="width: 16%; text-align: right" title="Number of Warrants Issued, Warrants outstanding, Beginning balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;3,853,566&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_989_ecustom--ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingWeightedAverageExercisePrice_iS_c20210101__20210630_zqVVyHompmr8" style="width: 16%; text-align: right" title="Weighted Average Exercise Price, Warrants outstanding, Beginning balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;1.35&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Warrants exercised during the six
    months ended June 30, 2021 (see Note 12)&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98F_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExercised_iN_di_c20210101__20210630_zHPeBD6O7QY5" style="border-bottom: Black 1.5pt solid; text-align: right" title="Number of Warrants Issued, Warrants exercised"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;(1,216,667&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;)&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_988_ecustom--ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExerciseInPeriodWeightedAverageExercisePrice_c20210101__20210630_pdd" style="padding-bottom: 1.5pt; text-align: right" title="Weighted Average Exercise Price, Warrants exercised"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;1.24&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Warrants outstanding at June 30,
    2021&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98A_eus-gaap--ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber_iE_c20210101__20210630_zBZnYIt9d2i2" style="border-bottom: Black 2.5pt double; text-align: right" title="Number of Warrants Issued, Warrants outstanding, Ending balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2,636,899&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98B_ecustom--ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingWeightedAverageExercisePrice_iE_c20210101__20210630_zHc7RRbT6gP6" style="padding-bottom: 2.5pt; text-align: right" title="Weighted Average Exercise Price, Warrants outstanding, Ending balance"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;1.40&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Aggregate intrinsic value of outstanding
    warrants at June 30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td id="xdx_98A_ecustom--ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionsOutstandingIntrinsicValue_iE_pp0p0_c20210101__20210630_zvgKs6wzw12k" style="border-bottom: Black 2.5pt double; text-align: right" title="Aggregate intrinsic value of outstanding warrants"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;159,857&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Weighted average remaining contractual terms at June 30, 2021&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span id="xdx_90E_ecustom--SharebasedCompensationArrangementBySharebasedPaymentAwardNonOptionsOutstandingWeightedAverageRemainingContractualTerm2_dtY_c20210101__20210630_ztBClSvcASZk" style="font: 10pt Times New Roman, Times, Serif"&gt;4.6
                                            &lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;years&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

</us-gaap:ScheduleOfStockholdersEquityNoteWarrantsOrRightsTextBlock>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber contextRef="AsOf2020-12-31" decimals="INF" unitRef="Shares">3853566</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber>
    <CLSN:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingWeightedAverageExercisePrice
      contextRef="AsOf2020-12-31"
      decimals="INF"
      unitRef="USDPShares">1.35</CLSN:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingWeightedAverageExercisePrice>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExercised
      contextRef="From2021-01-01to2021-06-30"
      decimals="INF"
      unitRef="Shares">1216667</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExercised>
    <CLSN:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExerciseInPeriodWeightedAverageExercisePrice
      contextRef="From2021-01-01to2021-06-30"
      decimals="INF"
      unitRef="USDPShares">1.24</CLSN:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExerciseInPeriodWeightedAverageExercisePrice>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber contextRef="AsOf2021-06-30" decimals="INF" unitRef="Shares">2636899</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber>
    <CLSN:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingWeightedAverageExercisePrice
      contextRef="AsOf2021-06-30"
      decimals="INF"
      unitRef="USDPShares">1.40</CLSN:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingWeightedAverageExercisePrice>
    <CLSN:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionsOutstandingIntrinsicValue contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">159857</CLSN:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionsOutstandingIntrinsicValue>
    <CLSN:SharebasedCompensationArrangementBySharebasedPaymentAwardNonOptionsOutstandingWeightedAverageRemainingContractualTerm2 contextRef="From2021-01-01to2021-06-30">P4Y7M6D</CLSN:SharebasedCompensationArrangementBySharebasedPaymentAwardNonOptionsOutstandingWeightedAverageRemainingContractualTerm2>
    <us-gaap:LesseeOperatingLeasesTextBlock contextRef="From2021-01-01to2021-06-30">&lt;p id="xdx_803_eus-gaap--LesseeOperatingLeasesTextBlock_z9DkxzCfoEOl" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
16. &lt;span id="xdx_823_zMZbPyAA0R7j"&gt;Leases&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span id="xdx_908_eus-gaap--LesseeOperatingLeaseDescription_c20110701__20110731" style="font: 10pt Times New Roman, Times, Serif"&gt;In
2011, the Company executed a lease (the &#x201c;Lease&#x201d;) with Brandywine Operating Partnership, L.P. (Brandywine), a Delaware
limited partnership, for a &lt;/span&gt;&lt;span id="xdx_904_eus-gaap--AreaOfLand_iI_uSqft_c20110731_zBXAAeWbCo04" style="font: 10pt Times New Roman, Times, Serif"&gt;10,870
square foot premises located in Lawrenceville, New Jersey and relocated its offices to Lawrenceville, New Jersey from Columbia,
Maryland. The Lease had an initial term of &lt;/span&gt;&lt;span id="xdx_900_eus-gaap--LesseeOperatingLeaseTermOfContract_iI_dtM_c20110731_zRZ2AjYuutEl" style="font: 10pt Times New Roman, Times, Serif"&gt;66 &lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;months.
In late 2015, Lenox Drive Office Park LLC purchased the real estate and office building and assumed the Lease. This Lease was set to
expire on &lt;span id="xdx_903_eus-gaap--LeaseExpirationDate1_dd_c20110701__20110731_zMDe2EcMKkyc"&gt;April 30, 2017&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;.
In April 2017, the Company and the landlord amended the Lease effective May 1, 2017. The 1&lt;sup&gt;st&lt;/sup&gt; Lease Amendment extended the
term of the agreement for an additional 64 months, reduced the premises to 7,565 square feet, reduced the monthly rent and provided
four months free rent. The monthly rent ranged from approximately $&lt;span id="xdx_90D_eus-gaap--PaymentsForRent_c20210101__20210630__us-gaap--TypeOfArrangementAxis__custom--FirstLeaseAmendmentMember__us-gaap--AwardTypeAxis__custom--FirstYearMember_pp0p0"&gt;18,900 &lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;in
the first year to approximately $&lt;span id="xdx_901_eus-gaap--PaymentsForRent_c20210101__20210630__us-gaap--TypeOfArrangementAxis__custom--FirstLeaseAmendmentMember__us-gaap--AwardTypeAxis__custom--FinalYearMember_pp0p0"&gt;20,500 &lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;in
the final year of the 1&lt;sup&gt;st&lt;/sup&gt; Lease Amendment. Effective January 9, 2019, the Company amended the current terms of the
1&lt;sup&gt;st&lt;/sup&gt; Lease Amendment to increase the size of the premises by 2,285 square feet to 9,850 square feet and also extended the
lease term by one year to September 1, 2023. The monthly rent ranges from approximately $&lt;span id="xdx_90C_eus-gaap--PaymentsForRent_c20210101__20210630__us-gaap--TypeOfArrangementAxis__custom--SecondLeaseAmendmentMember__us-gaap--AwardTypeAxis__custom--FirstYearMember_pp0p0"&gt;25,035 &lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;in
the first year to approximately $&lt;span id="xdx_908_eus-gaap--PaymentsForRent_c20210101__20210630__us-gaap--TypeOfArrangementAxis__custom--SecondLeaseAmendmentMember__us-gaap--AwardTypeAxis__custom--FinalYearMember_pp0p0"&gt;27,088 &lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;in
the final year of the 2&lt;sup&gt;nd&lt;/sup&gt; Lease Amendment.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span id="xdx_907_eus-gaap--LesseeOperatingLeaseDescription_c20180101__20180131__us-gaap--TypeOfArrangementAxis__custom--EGENAssetPurchaseAgreementMember" style="font: 10pt Times New Roman, Times, Serif"&gt;In
connection with the EGEN Asset Purchase Agreement in June 2014, the Company assumed the existing lease with another landlord for an &lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span id="xdx_904_eus-gaap--AreaOfLand_iI_uSqft_c20201231__srt--StatementGeographicalAxis__custom--HuntsvilleAlabamaMember_z9VwuUYmSqsc"&gt;11,500&lt;/span&gt;
square foot premises located in Huntsville Alabama. In January 2018, the Company and the Huntsville landlord entered into a new
60-month lease which reduced the premises to 9,049 square feet with rent payments of approximately $&lt;/span&gt;&lt;span id="xdx_90F_eus-gaap--PaymentsForRent_c20180101__20180131__us-gaap--TypeOfArrangementAxis__custom--EGENAssetPurchaseAgreementMember_pp0p0" style="font: 10pt Times New Roman, Times, Serif"&gt;18,100
per month.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;We
adopted ASC Topic 842 on January 1, 2019 using the modified retrospective transition method for all lease arrangements at the beginning
of the period of adoption. Results for reporting periods beginning January 1, 2019 are presented under ASC 842, while prior period amounts
were not adjusted and continue to be reported in accordance with our historic accounting under Topic 840, Leases. The standard had a
material impact on our Condensed Consolidated Balance Sheet but had no impact on our condensed consolidated net earnings and cash flows.
The most significant impact of adopting ASC Topic 842 was the recognition of the right-of-use (ROU) asset and lease liabilities for operating
leases, which are presented in the following three-line items on the Consolidated Condensed Balance Sheet: (i) operating lease right-of-use
asset; (ii) current operating lease liabilities; and (iii) operating lease liabilities. Therefore, on date of adoption of ASC Topic 842,
the Company recognized a ROU asset of $&lt;span id="xdx_90C_eus-gaap--OperatingLeaseRightOfUseAsset_iI_pn5n6_c20190102__us-gaap--AdjustmentsForNewAccountingPronouncementsAxis__us-gaap--AccountingStandardsUpdate201602Member_zEM04KJrnLI6"&gt;1.4
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million, operating lease liabilities, current
and non-current collectively, of $&lt;span id="xdx_90A_eus-gaap--OperatingLeaseLiability_iI_pn5n6_c20190102__us-gaap--AdjustmentsForNewAccountingPronouncementsAxis__us-gaap--AccountingStandardsUpdate201602Member_zZKWm4rGCLUd"&gt;1.5
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million and reduced other liabilities by approximately
$&lt;span id="xdx_909_eus-gaap--OtherLiabilities_iI_pn5n6_c20190102__us-gaap--AdjustmentsForNewAccountingPronouncementsAxis__us-gaap--AccountingStandardsUpdate201602Member_zNFw1wNi5JNa"&gt;0.1
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million. We elected the package of practical
expedients for leases that commenced before the effective date of ASC Topic 842 whereby we elected to not reassess the following: (i)
whether any expired or existing contracts contain leases; (ii) the lease classification for any expired or existing leases; and (iii)
initial direct costs for any existing leases. In addition, we have lease agreements with lease and non-lease components, and we have
elected the practical expedient for all underlying asset classes and account for them as a single lease component. We have no finance
leases. We determine if an arrangement is a lease at inception. We have operating leases for office space and research and development
facilities. Neither of our leases include options to renew, however, one contains an option for early termination. We considered the
option of early termination in measurement of right-of-use assets and lease liabilities and we determined it is not reasonably certain
to be terminated. In connection with the 2&lt;sup&gt;nd&lt;/sup&gt; Lease Amendment for the New Jersey office lease in January 2019, the Company
considered this as one modified lease and not as two separate leases. Therefore, in January 2019, the Company determined this lease was
an operating lease and remeasured the ROU asset and lease liability. Therefore, the Company increased the ROU asset and operating lease
liabilities by $&lt;span id="xdx_903_eus-gaap--OperatingLeaseRightOfUseAsset_iI_pn5n6_c20190102_zlH6INxpkBfh"&gt;0.4&lt;/span&gt;&lt;/span&gt; &lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million
to $&lt;span id="xdx_90D_eus-gaap--RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability_pn5n6_c20181230__20190102_z7H2dtHkWFhg"&gt;1.8
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million and $&lt;span id="xdx_904_eus-gaap--OperatingLeaseLiability_iI_pn5n6_c20190102_zi4Bxybj99Fe"&gt;1.9
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million, respectively.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;




&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p id="xdx_890_eus-gaap--LesseeOperatingLeaseLiabilityMaturityTableTextBlock_z4RySOfHK1V8" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Following
is a table of the lease payments and maturity of our operating lease liabilities as of June 30, 2021:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8B7_zyKGaaw0an66" style="display: none"&gt;Schedule
of Lease Payments and Maturity of Operating Lease Liabilities&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_495_20210630_zE9yRm7JS5b1" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;For
                                            the&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;year
                                            ending&lt;br/&gt; June 30,&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40C_eus-gaap--LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_iI_pp0p0_maLOLLPzRpH_zbZY95qxpQc5" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; width: 80%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Remainder of 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;266,188&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_402_eus-gaap--LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_iI_pp0p0_maLOLLPzRpH_z06zh07qOhj9" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2022&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;535,579&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40B_eus-gaap--LesseeOperatingLeaseLiabilityPaymentsDueYearThree_iI_pp0p0_maLOLLPzRpH_zV55xrWo0Y9h" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2023&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;233,116&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_409_ecustom--LesseeOperatingLeaseLiabilityPaymentsDueAfterYearThreeAndThereAfter_iI_pp0p0_maLOLLPzRpH_z8CQV3Hxu8o7" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2024 and thereafter&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1316"&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;-&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40F_eus-gaap--LesseeOperatingLeaseLiabilityPaymentsDue_iTI_pp0p0_mtLOLLPzRpH_zxkN4KFxThYc" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Subtotal future lease payments&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;1,034,883&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_409_ecustom--OperatingLeaseImputedInterest_iNI_pp0p0_di_zxa1wWigBvZ1" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="padding-left: 10pt; text-align: left; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Less
    imputed interest&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;(101,664&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;)&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_404_eus-gaap--OperatingLeaseLiability_iI_pp0p0_zI5OOCubORAk" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Total lease liabilities&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;933,219&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Weighted average remaining
    life&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span id="xdx_905_eus-gaap--OperatingLeaseWeightedAverageRemainingLeaseTerm1_iI_dtY_c20210630_zDfXmVicMJyg" style="font: 10pt Times New Roman, Times, Serif"&gt;2.0
                                            &lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;years&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Weighted average discount
    rate&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;&lt;span id="xdx_90F_eus-gaap--OperatingLeaseWeightedAverageDiscountRatePercent_iI_pid_dp_c20210630_zcTGE2yTgdg2" style="font-family: Times New Roman, Times, Serif"&gt;9.98&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

&lt;p id="xdx_8A1_zAGTiCFuhki3" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;For
the three-month and six-month periods ended June 30, 2021, operating lease expense was $&lt;span id="xdx_907_eus-gaap--OperatingLeaseCost_pp0p0_c20210401__20210630__us-gaap--TypeOfArrangementAxis__custom--OperatingLeasesMember_zGSiDGXz7GB4"&gt;130,595
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;and $&lt;span id="xdx_90A_eus-gaap--OperatingLeaseCost_pp0p0_c20210101__20210630__us-gaap--TypeOfArrangementAxis__custom--OperatingLeasesMember_zluoCzg0oAki"&gt;261,190&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;,
respectively and cash paid for operating leases included in operating cash flows was $&lt;span id="xdx_90B_eus-gaap--OperatingLeasePayments_pp0p0_c20210401__20210630__us-gaap--TypeOfArrangementAxis__custom--OperatingLeasesMember_zO3k0KyjPhJ4"&gt;132,684
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;and $&lt;span id="xdx_90D_eus-gaap--OperatingLeasePayments_pp0p0_c20210101__20210630__us-gaap--TypeOfArrangementAxis__custom--OperatingLeasesMember_zObdCU54sZtb"&gt;264,546&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;,
respectively. For the three-month and six-month periods ended June 30, 2020, operating lease expense was $&lt;span id="xdx_90A_eus-gaap--OperatingLeaseCost_pp0p0_c20200401__20200630__us-gaap--TypeOfArrangementAxis__custom--OperatingLeasesMember_zG5j5lJcByy8"&gt;130,595
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;and $&lt;span id="xdx_903_eus-gaap--OperatingLeaseCost_c20200101__20200630__us-gaap--TypeOfArrangementAxis__custom--OperatingLeasesMember_pp0p0"&gt;261,190&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;,
respectively and cash paid for operating leases included in operating cash flows was $&lt;span id="xdx_906_eus-gaap--OperatingLeasePayments_pp0p0_c20200401__20200630__us-gaap--TypeOfArrangementAxis__custom--OperatingLeasesMember_zwDlLDPXz3Ih"&gt;131,452
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;and $&lt;span id="xdx_90D_eus-gaap--OperatingLeasePayments_c20200101__20200630__us-gaap--TypeOfArrangementAxis__custom--OperatingLeasesMember_pp0p0"&gt;262,084&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;,
respectively.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

</us-gaap:LesseeOperatingLeasesTextBlock>
    <us-gaap:LesseeOperatingLeaseDescription contextRef="From2011-07-012011-07-31">In
2011, the Company executed a lease (the &#x201c;Lease&#x201d;) with Brandywine Operating Partnership, L.P. (Brandywine), a Delaware
limited partnership, for a</us-gaap:LesseeOperatingLeaseDescription>
    <us-gaap:AreaOfLand contextRef="AsOf2011-07-31" decimals="INF" unitRef="Sqft">10870</us-gaap:AreaOfLand>
    <us-gaap:LesseeOperatingLeaseTermOfContract contextRef="AsOf2011-07-31">P66M</us-gaap:LesseeOperatingLeaseTermOfContract>
    <us-gaap:LeaseExpirationDate1 contextRef="From2011-07-012011-07-31">2017-04-30</us-gaap:LeaseExpirationDate1>
    <us-gaap:PaymentsForRent
      contextRef="From2021-01-012021-06-30_custom_FirstLeaseAmendmentMember_custom_FirstYearMember"
      decimals="0"
      unitRef="USD">18900</us-gaap:PaymentsForRent>
    <us-gaap:PaymentsForRent
      contextRef="From2021-01-012021-06-30_custom_FirstLeaseAmendmentMember_custom_FinalYearMember"
      decimals="0"
      unitRef="USD">20500</us-gaap:PaymentsForRent>
    <us-gaap:PaymentsForRent
      contextRef="From2021-01-012021-06-30_custom_SecondLeaseAmendmentMember_custom_FirstYearMember"
      decimals="0"
      unitRef="USD">25035</us-gaap:PaymentsForRent>
    <us-gaap:PaymentsForRent
      contextRef="From2021-01-012021-06-30_custom_SecondLeaseAmendmentMember_custom_FinalYearMember"
      decimals="0"
      unitRef="USD">27088</us-gaap:PaymentsForRent>
    <us-gaap:LesseeOperatingLeaseDescription contextRef="From2018-01-012018-01-31_custom_EGENAssetPurchaseAgreementMember">In
connection with the EGEN Asset Purchase Agreement in June 2014, the Company assumed the existing lease with another landlord for an</us-gaap:LesseeOperatingLeaseDescription>
    <us-gaap:AreaOfLand
      contextRef="AsOf2020-12-31_custom_HuntsvilleAlabamaMember"
      decimals="INF"
      unitRef="Sqft">11500</us-gaap:AreaOfLand>
    <us-gaap:PaymentsForRent
      contextRef="From2018-01-012018-01-31_custom_EGENAssetPurchaseAgreementMember"
      decimals="0"
      unitRef="USD">18100</us-gaap:PaymentsForRent>
    <us-gaap:OperatingLeaseRightOfUseAsset
      contextRef="AsOf2019-01-02_us-gaap_AccountingStandardsUpdate201602Member"
      decimals="-5"
      unitRef="USD">1400000</us-gaap:OperatingLeaseRightOfUseAsset>
    <us-gaap:OperatingLeaseLiability
      contextRef="AsOf2019-01-02_us-gaap_AccountingStandardsUpdate201602Member"
      decimals="-5"
      unitRef="USD">1500000</us-gaap:OperatingLeaseLiability>
    <us-gaap:OtherLiabilities
      contextRef="AsOf2019-01-02_us-gaap_AccountingStandardsUpdate201602Member"
      decimals="-5"
      unitRef="USD">100000</us-gaap:OtherLiabilities>
    <us-gaap:OperatingLeaseRightOfUseAsset contextRef="AsOf2019-01-02" decimals="-5" unitRef="USD">400000</us-gaap:OperatingLeaseRightOfUseAsset>
    <us-gaap:RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability
      contextRef="From2018-12-302019-01-02"
      decimals="-5"
      unitRef="USD">1800000</us-gaap:RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability>
    <us-gaap:OperatingLeaseLiability contextRef="AsOf2019-01-02" decimals="-5" unitRef="USD">1900000</us-gaap:OperatingLeaseLiability>
    <us-gaap:LesseeOperatingLeaseLiabilityMaturityTableTextBlock contextRef="From2021-01-01to2021-06-30">&lt;p id="xdx_890_eus-gaap--LesseeOperatingLeaseLiabilityMaturityTableTextBlock_z4RySOfHK1V8" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Following
is a table of the lease payments and maturity of our operating lease liabilities as of June 30, 2021:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;span id="xdx_8B7_zyKGaaw0an66" style="display: none"&gt;Schedule
of Lease Payments and Maturity of Operating Lease Liabilities&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; border-collapse: collapse; width: 100%"&gt;
  &lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td colspan="2" id="xdx_495_20210630_zE9yRm7JS5b1" style="border-bottom: Black 1.5pt solid; text-align: center"&gt;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;For
                                            the&lt;/b&gt;&lt;/span&gt;&lt;/p&gt; &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;year
                                            ending&lt;br/&gt; June 30,&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40C_eus-gaap--LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_iI_pp0p0_maLOLLPzRpH_zbZY95qxpQc5" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; width: 80%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Remainder of 2021&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 2%"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 16%; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;266,188&lt;/span&gt;&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_402_eus-gaap--LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_iI_pp0p0_maLOLLPzRpH_z06zh07qOhj9" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2022&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;535,579&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40B_eus-gaap--LesseeOperatingLeaseLiabilityPaymentsDueYearThree_iI_pp0p0_maLOLLPzRpH_zV55xrWo0Y9h" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2023&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;233,116&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_409_ecustom--LesseeOperatingLeaseLiabilityPaymentsDueAfterYearThreeAndThereAfter_iI_pp0p0_maLOLLPzRpH_z8CQV3Hxu8o7" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;2024 and thereafter&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&lt;span style="-sec-ix-hidden: xdx2ixbrl1316"&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;-&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_40F_eus-gaap--LesseeOperatingLeaseLiabilityPaymentsDue_iTI_pp0p0_mtLOLLPzRpH_zxkN4KFxThYc" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Subtotal future lease payments&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;1,034,883&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_409_ecustom--OperatingLeaseImputedInterest_iNI_pp0p0_di_zxa1wWigBvZ1" style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="padding-left: 10pt; text-align: left; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Less
    imputed interest&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;(101,664&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;)&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr id="xdx_404_eus-gaap--OperatingLeaseLiability_iI_pp0p0_zI5OOCubORAk" style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Total lease liabilities&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;$&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;933,219&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Weighted average remaining
    life&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1.5pt solid; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 1.5pt solid; text-align: right"&gt;&lt;span id="xdx_905_eus-gaap--OperatingLeaseWeightedAverageRemainingLeaseTerm1_iI_dtY_c20210630_zDfXmVicMJyg" style="font: 10pt Times New Roman, Times, Serif"&gt;2.0
                                            &lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;years&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 1.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: right"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;Weighted average discount
    rate&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;&lt;span id="xdx_90F_eus-gaap--OperatingLeaseWeightedAverageDiscountRatePercent_iI_pid_dp_c20210630_zcTGE2yTgdg2" style="font-family: Times New Roman, Times, Serif"&gt;9.98&lt;/span&gt;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&lt;span style="font-family: Times New Roman, Times, Serif"&gt;%&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;

</us-gaap:LesseeOperatingLeaseLiabilityMaturityTableTextBlock>
    <us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">266188</us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths>
    <us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">535579</us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo>
    <us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">233116</us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree>
    <us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">1034883</us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue>
    <CLSN:OperatingLeaseImputedInterest contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">101664</CLSN:OperatingLeaseImputedInterest>
    <us-gaap:OperatingLeaseLiability contextRef="AsOf2021-06-30" decimals="0" unitRef="USD">933219</us-gaap:OperatingLeaseLiability>
    <us-gaap:OperatingLeaseWeightedAverageRemainingLeaseTerm1 contextRef="AsOf2021-06-30">P2Y</us-gaap:OperatingLeaseWeightedAverageRemainingLeaseTerm1>
    <us-gaap:OperatingLeaseWeightedAverageDiscountRatePercent
      contextRef="AsOf2021-06-30"
      decimals="INF"
      unitRef="Percentage">0.0998</us-gaap:OperatingLeaseWeightedAverageDiscountRatePercent>
    <us-gaap:OperatingLeaseCost
      contextRef="From2021-04-012021-06-30_custom_OperatingLeasesMember"
      decimals="0"
      unitRef="USD">130595</us-gaap:OperatingLeaseCost>
    <us-gaap:OperatingLeaseCost
      contextRef="From2021-01-012021-06-30_custom_OperatingLeasesMember"
      decimals="0"
      unitRef="USD">261190</us-gaap:OperatingLeaseCost>
    <us-gaap:OperatingLeasePayments
      contextRef="From2021-04-012021-06-30_custom_OperatingLeasesMember"
      decimals="0"
      unitRef="USD">132684</us-gaap:OperatingLeasePayments>
    <us-gaap:OperatingLeasePayments
      contextRef="From2021-01-012021-06-30_custom_OperatingLeasesMember"
      decimals="0"
      unitRef="USD">264546</us-gaap:OperatingLeasePayments>
    <us-gaap:OperatingLeaseCost
      contextRef="From2020-04-012020-06-30_custom_OperatingLeasesMember"
      decimals="0"
      unitRef="USD">130595</us-gaap:OperatingLeaseCost>
    <us-gaap:OperatingLeaseCost
      contextRef="From2020-01-012020-06-30_custom_OperatingLeasesMember"
      decimals="0"
      unitRef="USD">261190</us-gaap:OperatingLeaseCost>
    <us-gaap:OperatingLeasePayments
      contextRef="From2020-04-012020-06-30_custom_OperatingLeasesMember"
      decimals="0"
      unitRef="USD">131452</us-gaap:OperatingLeasePayments>
    <us-gaap:OperatingLeasePayments
      contextRef="From2020-01-012020-06-30_custom_OperatingLeasesMember"
      decimals="0"
      unitRef="USD">262084</us-gaap:OperatingLeasePayments>
    <CLSN:LicensingTransactionTextBlock contextRef="From2021-01-01to2021-06-30">&lt;p id="xdx_80D_ecustom--LicensingTransactionTextBlock_zO0A5bLZs45e" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
17. &lt;span id="xdx_828_zHhke97mWmbc"&gt;Technology Development and Licensing Agreements&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
May 7, 2012, the Company entered into a long-term commercial supply agreement with Zhejiang Hisun Pharmaceutical Co. Ltd. (Hisun) for
the production of ThermoDox&lt;sup&gt;&#xae;&lt;/sup&gt; in the China territory. In accordance with the terms of the agreement, Hisun will be responsible
for providing all of the technical and regulatory support services, including the costs of all technical transfer, registration and bioequivalence
studies, technical transfer costs, Celsion consultative support costs and the purchase of any necessary equipment and additional facility
costs necessary to support capacity requirements for the manufacture of ThermoDox&lt;sup&gt;&#xae;&lt;/sup&gt;. Celsion will repay Hisun for the aggregate
amount of these development costs and fees commencing on the successful completion of three registration batches of ThermoDox&lt;sup&gt;&#xae;&lt;/sup&gt;.
Hisun is also obligated to certain performance requirements under the agreement. The agreement will initially be limited to a percentage
of the production requirements of ThermoDox&lt;sup&gt;&#xae;&lt;/sup&gt; in the China territory with Hisun retaining an option for additional global
supply after local regulatory approval in the China territory. In addition, Hisun will collaborate with Celsion around the regulatory
approval activities for ThermoDox&lt;sup&gt;&#xae; &lt;/sup&gt;with the China State Food and Drug Administration (CHINA FDA). During the first quarter
of 2015, Hisun completed the successful manufacture of three registration batches of ThermoDox&lt;sup&gt;&#xae;&lt;/sup&gt;.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
January 18, 2013, we entered into a technology development contract with Hisun, pursuant to which Hisun paid us a non-refundable research
and development fee of $&lt;span id="xdx_900_eus-gaap--ProceedsFromLicenseFeesReceived_pn6n6_c20130117__20130118__us-gaap--AccountsNotesLoansAndFinancingReceivablesByLegalEntityOfCounterpartyTypeAxis__custom--HisunMember_zTQp5y8IH3Bg"&gt;5
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million to support our development of ThermoDox&lt;sup&gt;&#xae;
&lt;/sup&gt;in mainland China, Hong Kong and Macau (the China territory). Following our announcement on January 31, 2013 that the HEAT study
failed to meet its primary endpoint, Celsion and Hisun have agreed that the Technology Development Contract entered into on January 18,
2013 will remain in effect while the parties continue to collaborate and are evaluating the next steps in relation to ThermoDox&lt;sup&gt;&#xae;&lt;/sup&gt;,
which include the sub-group analysis of patients in the Phase III HEAT Study for the hepatocellular carcinoma clinical indication and
other activities to further the development of ThermoDox&lt;sup&gt;&#xae; &lt;/sup&gt;for the Greater China market. The $&lt;span id="xdx_904_eus-gaap--DeferredRevenue_iI_pn5n6_c20130118__us-gaap--AccountsNotesLoansAndFinancingReceivablesByLegalEntityOfCounterpartyTypeAxis__custom--HisunMember_z8sj8b8g9WSh"&gt;5.0
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;million received as a non-refundable payment
from Hisun in the first quarter 2013 has been recorded to deferred revenue and will continue to be amortized over the &lt;span id="xdx_90E_ecustom--DeferredRevenueAmortizationPeriod_dtY_c20130117__20130118__us-gaap--AccountsNotesLoansAndFinancingReceivablesByLegalEntityOfCounterpartyTypeAxis__custom--HisunMember_zo2O5Gnooo6f"&gt;10
&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;-year term of the agreement, until such time
as the parties find a mutually acceptable path forward on the development of ThermoDox&lt;sup&gt;&#xae;&lt;/sup&gt; based on findings of the ongoing
post-study analysis of the HEAT Study data.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
July 19, 2013, the Company and Hisun entered into a Memorandum of Understanding to pursue ongoing cooperation for the continued clinical
development of ThermoDox&lt;sup&gt;&#xae;&lt;/sup&gt; as well as the technology transfer relating to the commercial manufacture of ThermoDox&lt;sup&gt;&#xae;
&lt;/sup&gt;for the China territory. This expanded level of cooperation includes development of the next generation liposomal formulation with
the goal of creating safer, more efficacious versions of marketed cancer chemotherapeutics.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Among
the key provisions of the Celsion-Hisun Memorandum of Understanding are:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 0.5in; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;&#x25cf;&lt;/b&gt;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Hisun
    will provide the Company with internal resources necessary to complete the technology transfer of the Company&#x2019;s proprietary
    manufacturing process and the production of registration batches for the China territory;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;&#x25cf;&lt;/b&gt;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Hisun
    will coordinate with the Company around the clinical and regulatory approval activities for ThermoDox&lt;sup&gt;&#xae;&lt;/sup&gt; as well as
    other liposomal formations with the CHINA FDA; and&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;&#x25cf;&lt;/b&gt;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Hisun
    will be granted a right of &lt;i&gt;first&lt;/i&gt; offer for a commercial license to ThermoDox&lt;sup&gt;&#xae;&lt;/sup&gt; for the sale and distribution
    of ThermoDox&lt;sup&gt;&#xae; &lt;/sup&gt;in the China territory.&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;
&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;




&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
August 8, 2016, we signed a Technology Transfer, Manufacturing and Commercial Supply Agreement (&#x201c;GEN-1 Agreement&#x201d;) with Hisun
to pursue an expanded partnership for the technology transfer relating to the clinical and commercial manufacture and supply of GEN-1,
Celsion&#x2019;s proprietary gene mediated, IL-12 immunotherapy, for the greater China territory, with the option to expand into other
countries in the rest of the world after all necessary regulatory approvals are in effect. The GEN-1 Agreement will help to support supply
for both ongoing and planned clinical studies in the U.S., and for potential future studies of GEN-1 in China. GEN-1 is currently being
evaluated by Celsion in first line ovarian cancer patients.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Key
provisions of the GEN-1 Agreement are as follows:&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0 0 0 9.9pt"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="font: 10pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; width: 0.5in"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;&#x25cf;&lt;/b&gt;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;the
    GEN-1 Agreement has targeted unit costs for clinical supplies of GEN-1 that are substantially competitive with the Company&#x2019;s
    current suppliers;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;&#x25cf;&lt;/b&gt;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;once
    approved, the cost structure for GEN-1 will support rapid market adoption and significant gross margins across global markets;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;&#x25cf;&lt;/b&gt;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Celsion
    will provide Hisun a certain percentage of China&#x2019;s commercial unit demand, and separately of global commercial unit demand,
    subject to regulatory approval;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;&#x25cf;&lt;/b&gt;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Hisun
    and Celsion will commence technology transfer activities relating to the manufacture of GEN-1, including all studies required by
    CHINA FDA for site approval; and&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;tr style="font: 10pt Times New Roman, Times, Serif; vertical-align: top"&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;&#x25cf;&lt;/b&gt;&lt;/span&gt;&lt;/td&gt;
    &lt;td style="font: 10pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;Hisun
    will collaborate with Celsion around the regulatory approval activities for GEN-1 with the CHINA FDA. A local China partner affords
    Celsion access to accelerated CHINA FDA review and potential regulatory exclusivity for the approved indication.&lt;/span&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;
&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;The
Company evaluated the Hisun arrangement in accordance with ASC 606 and determined that its performance obligations under the agreement
include the non-exclusive, royalty-free license, research and development services to be provided by the Company, and its obligation
to serve on a joint committee. The Company concluded that the license was not distinct since its value is closely tied to the ongoing
research and development activities. As such, the license and the research and development services are bundled as a single performance
obligation. Since the provision of the license and research and development services are considered a single performance obligation,
the $&lt;span id="xdx_900_ecustom--UpfrontPaymentBeingRecognized_c20210101__20210630_pp0p0"&gt;5,000,000&lt;/span&gt;&lt;/span&gt; &lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;upfront
payment is being recognized as revenue ratably through 2022.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

</CLSN:LicensingTransactionTextBlock>
    <us-gaap:ProceedsFromLicenseFeesReceived
      contextRef="From2013-01-172013-01-18_custom_HisunMember"
      decimals="-6"
      unitRef="USD">5000000</us-gaap:ProceedsFromLicenseFeesReceived>
    <us-gaap:DeferredRevenue
      contextRef="AsOf2013-01-18_custom_HisunMember"
      decimals="-5"
      unitRef="USD">5000000.0</us-gaap:DeferredRevenue>
    <CLSN:DeferredRevenueAmortizationPeriod contextRef="From2013-01-172013-01-18_custom_HisunMember">P10Y</CLSN:DeferredRevenueAmortizationPeriod>
    <CLSN:UpfrontPaymentBeingRecognized
      contextRef="From2021-01-01to2021-06-30"
      decimals="0"
      unitRef="USD">5000000</CLSN:UpfrontPaymentBeingRecognized>
    <us-gaap:CommitmentsAndContingenciesDisclosureTextBlock contextRef="From2021-01-01to2021-06-30">&lt;p id="xdx_80A_eus-gaap--CommitmentsAndContingenciesDisclosureTextBlock_zq4ODTqpkxA7" style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&lt;b&gt;Note
18. &lt;span id="xdx_828_zf71VXYqeqia"&gt;Commitments and Contingencies&lt;/span&gt;&lt;/b&gt;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
September 20, 2019, a purported stockholder of the Company filed a derivative and putative class action lawsuit against the Company and
certain officers and directors (the &#x201c;Shareholder Action&#x201d;). The Company was a defendant in this derivative and putative class
action lawsuit in the Superior Court of New Jersey, Chancery Division, filed by a shareholder against the Company (as both a class action
defendant and nominal defendant), and certain of its officers and directors (the &#x201c;Individual Defendants&#x201d;), with the caption
&lt;i&gt;O&#x2019;Connor v. Braun et al., Docket No. MER-C-000068-19&lt;/i&gt; (the &#x201c;Shareholder Action&#x201d;). The Shareholder Action alleged
breaches of the defendants&#x2019; fiduciary duties based on allegations that the defendants omitted or made improper statements when
seeking shareholder approval of the 2018 Stock Incentive Plan. The Shareholder Action sought, among other things, any damages sustained
by the Company as a result of the defendants&#x2019; alleged wrongdoing, a declaratory judgment against all defendants invalidating the
2018 Stock Incentive Plan and declaring any awards made under the Plan invalid, rescinded, and subject to disgorgement, an order disgorging
the equity awards granted to the Individual Defendants under the 2018 Stock Incentive Plan, and attorneys&#x2019; fees and costs.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
April 24, 2020, the Company, the Individual Defendants, and the plaintiff (the &#x201c;Parties&#x201d;) entered into a Settlement Agreement
and Release (the &#x201c;Settlement Agreement&#x201d;), which memorializes the terms of the Parties&#x2019; settlement of the Shareholder
Action (the &#x201c;Settlement&#x201d;). The Settlement calls for repricing of certain stock options and payment of plaintiff legal fees
of $&lt;span id="xdx_90B_eus-gaap--LitigationSettlementExpense_c20200422__20200424_pp0p0"&gt;187,500&lt;/span&gt;&lt;/span&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;.
On July 24, 2020, the Court issued an order approving the Parties&#x2019; proposed form of notice to shareholders regarding the Settlement.
A hearing was held on September 8, 2020 whereby the Court issued a final approval approving the Settlement. Pursuant to the Settlement,
the Company paid $&lt;span id="xdx_90E_eus-gaap--PaymentsForLegalSettlements_c20201001__20201002_pp0p0"&gt;187,500&lt;/span&gt;&lt;/span&gt; &lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;on
October 1, 2020. Without admitting the validity of any of the claims asserted in the Shareholder Action, or any liability with respect
thereto, and expressly denying all allegations of wrongdoing, fault, liability, or damage against the Company and the Individual Defendants
arising out of any of the conduct, statements, acts or omissions alleged, or that could have been alleged, in the Shareholder Action,
the Company and the Individual Defendants concluded that it was desirable that the claims be settled on the terms and subject to the
conditions set forth in the Settlement Agreement. The Company and the Individual Defendants entered into the Settlement Agreement for
settlement purposes only and solely to avoid the cost and disruption of further litigation.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;On
October 29, 2020, a putative securities class action was filed against the Company and certain of its officers and directors (the &#x201c;Spar
Individual Defendants&#x201d;) in the U.S. District Court for the District of New Jersey, captioned &lt;i&gt;Spar v. Celsion Corporation, et
al.&lt;/i&gt;, Case No. 1:20-cv-15228. The plaintiff alleges that the Company and Individual Defendants made false and misleading statements
regarding one of the Company&#x2019;s product candidates, ThermoDox&lt;sup&gt;&#xae;&lt;/sup&gt;, and brings claims for damages under Section 10(b)
of the Exchange Act and Rule 10b-5 promulgated thereunder against all Defendants, and under Section 20(a) of the Exchange Act of 1934
against the Spar Individual Defendants. The Company believes that the case is without merit and intends to defend it vigorously. Due
to the early stage of the case neither the likelihood that a loss, if any, will be realized, nor an estimate of possible loss or range
of loss, if any, can be determined.&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;&#160;&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;span style="font: 10pt Times New Roman, Times, Serif"&gt;In
February 2021, a derivative shareholder lawsuit was filed against the Company, as the nominal defendant, and certain of its directors
and officers as defendants in the U.S. District Court for the District of New Jersey, captioned &lt;i&gt;Fidler v. Michael H. Tardugno et al.&lt;/i&gt;,
Case No. 3:21-cv-02662. The plaintiff alleges breach of fiduciary duty and other claims arising out of alleged statements made by certain
of the Company&#x2019;s directors and/or officers regarding ThermoDox&lt;sup&gt;&#xae;.&lt;/sup&gt; The Company believes it has meritorious defenses
to these claims and intends to vigorously contest this suit. Due to the early stage of the case neither the likelihood that a loss, if
any, will be realized, nor an estimate of possible loss or range of loss, if any, can be determined.&lt;/span&gt;&lt;/p&gt;

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