<?xml version="1.0" encoding="US-ASCII" ?>
    <!-- Field: Doc-Info; Name: Generator; Value: GoFiler Complete; Version: 5.8a -->
    <!-- Field: Doc-Info; Name: VendorURI; Value: http://www.novaworks.com -->
    <!-- Field: Doc-Info; Name: Source; Value: CLSN %2D 20210331 10Q Q1 DFN.xfr; Date: 2021%2D05%2D12T18:52:19Z -->
    <!-- Field: Doc-Info; Name: Status; Value: 0x00000000 -->
<xbrli:xbrl xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xbrli="http://www.xbrl.org/2003/instance" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xmlns:xbrldi="http://xbrl.org/2006/xbrldi" xmlns:dei="http://xbrl.sec.gov/dei/2021" xmlns:ref="http://www.xbrl.org/2006/ref" xmlns:iso4217="http://www.xbrl.org/2003/iso4217" xmlns:utr="http://www.xbrl.org/2009/utr" xmlns:us-gaap="http://fasb.org/us-gaap/2021-01-31" xmlns:us-roles="http://fasb.org/us-roles/2021-01-31" xmlns:dtr-types="http://www.xbrl.org/dtr/type/2020-01-21" xmlns:us-types="http://fasb.org/us-types/2021-01-31" xmlns:country="http://xbrl.sec.gov/country/2021" xmlns:stpr="http://xbrl.sec.gov/stpr/2021" xmlns:srt="http://fasb.org/srt/2021-01-31" xmlns:CLSN="http://celsion.com/20210331">
    <link:schemaRef xlink:href="clsn-20210331.xsd" xlink:type="simple" />
    <xbrli:context id="From2021-01-01to2021-03-31">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-01</xbrli:startDate>
        <xbrli:endDate>2021-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2018-01-01to2018-12-31_custom_EGENIncMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:BusinessAcquisitionAxis">CLSN:EGENIncMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2018-01-01</xbrli:startDate>
        <xbrli:endDate>2018-12-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2018-06-26to2018-06-27_custom_InitialHorizonCreditAgreementMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:InitialHorizonCreditAgreementMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2018-06-26</xbrli:startDate>
        <xbrli:endDate>2018-06-27</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2018-01-01to2018-12-31_custom_EGENIncMember_custom_GlioblastomaMultiformeBrainCancerMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:BusinessAcquisitionAxis">CLSN:EGENIncMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:ContingentConsiderationByTypeAxis">CLSN:GlioblastomaMultiformeBrainCancerMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2018-01-01</xbrli:startDate>
        <xbrli:endDate>2018-12-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-01-01to2021-03-31_us-gaap_GoodwillMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByAssetClassAxis">us-gaap:GoodwillMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-01</xbrli:startDate>
        <xbrli:endDate>2021-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-01-01to2021-03-31_custom_IPRAndDMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByAssetClassAxis">CLSN:IPRAndDMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-01</xbrli:startDate>
        <xbrli:endDate>2021-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-03-31">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-12-31_custom_AspirePurchaseAgreementsMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:AspirePurchaseAgreementsMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-12-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-01-01to2021-03-31_us-gaap_NoncompeteAgreementsMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:FiniteLivedIntangibleAssetsByMajorClassAxis">us-gaap:NoncompeteAgreementsMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-01</xbrli:startDate>
        <xbrli:endDate>2021-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-01-01to2021-03-31_custom_EGENIncMember_custom_IPRAndDDrugTechnologyPlatformsMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:BusinessAcquisitionAxis">CLSN:EGENIncMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="dei:LegalEntityAxis">CLSN:IPRAndDDrugTechnologyPlatformsMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-01</xbrli:startDate>
        <xbrli:endDate>2021-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-01-01to2021-03-31_custom_IPRAndDDrugTechnologyPlatformsMember_custom_OvarianCancerMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="dei:LegalEntityAxis">CLSN:IPRAndDDrugTechnologyPlatformsMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:ContingentConsiderationByTypeAxis">CLSN:OvarianCancerMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-01</xbrli:startDate>
        <xbrli:endDate>2021-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-01-01to2021-03-31_custom_IPRAndDDrugTechnologyPlatformsMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="dei:LegalEntityAxis">CLSN:IPRAndDDrugTechnologyPlatformsMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-01</xbrli:startDate>
        <xbrli:endDate>2021-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-01-01to2021-03-31_custom_EGENIncMember_custom_PurchaseAgreementMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:BusinessAcquisitionAxis">CLSN:EGENIncMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:PurchaseAgreementMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-01</xbrli:startDate>
        <xbrli:endDate>2021-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-03-31_custom_EGENIncMember_custom_PurchaseAgreementMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:BusinessAcquisitionAxis">CLSN:EGENIncMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:PurchaseAgreementMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-01-01to2021-03-31_custom_EGENIncMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:BusinessAcquisitionAxis">CLSN:EGENIncMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-01</xbrli:startDate>
        <xbrli:endDate>2021-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2020-01-01to2020-03-31_custom_InitialHorizonCreditAgreementAmendmentMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:DebtInstrumentAxis">CLSN:InitialHorizonCreditAgreementAmendmentMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2020-01-01</xbrli:startDate>
        <xbrli:endDate>2020-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2020-01-01to2020-03-31">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2020-01-01</xbrli:startDate>
        <xbrli:endDate>2020-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-01-01to2021-03-31_custom_InitialHorizonCreditAgreementAmendmentMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:DebtInstrumentAxis">CLSN:InitialHorizonCreditAgreementAmendmentMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-01</xbrli:startDate>
        <xbrli:endDate>2021-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-05-13">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-05-13</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2020-08-27to2020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:AmendmentToHorizonCreditAgreementMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="dei:LegalEntityAxis">CLSN:HorizonTechnologyFinanceCorporationMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2020-08-27</xbrli:startDate>
        <xbrli:endDate>2020-08-28</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:AmendmentToHorizonCreditAgreementMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="dei:LegalEntityAxis">CLSN:HorizonTechnologyFinanceCorporationMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-08-28</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember_custom_OneMonthLondonInterbankOfferedRateLIBORExceedsTwoPeercentagePlusMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:AmendmentToHorizonCreditAgreementMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="dei:LegalEntityAxis">CLSN:HorizonTechnologyFinanceCorporationMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:VariableRateAxis">CLSN:OneMonthLondonInterbankOfferedRateLIBORExceedsTwoPeercentagePlusMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-08-28</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember_us-gaap_CommonStockMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:AmendmentToHorizonCreditAgreementMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="dei:LegalEntityAxis">CLSN:HorizonTechnologyFinanceCorporationMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:CommonStockMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-08-28</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2018-06-27_custom_InitialHorizonCreditAgreementMember_us-gaap_CommonStockMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:InitialHorizonCreditAgreementMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:CommonStockMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2018-06-27</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-03-31_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:AmendmentToHorizonCreditAgreementMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="dei:LegalEntityAxis">CLSN:HorizonTechnologyFinanceCorporationMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-12-31">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-12-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-12-31_us-gaap_NoncompeteAgreementsMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:FiniteLivedIntangibleAssetsByMajorClassAxis">us-gaap:NoncompeteAgreementsMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-12-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-12-31_custom_IPRAndDMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByAssetClassAxis">CLSN:IPRAndDMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-12-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-12-31_us-gaap_GoodwillMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByAssetClassAxis">us-gaap:GoodwillMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-12-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2020-01-01to2020-03-31_custom_IPRAndDDrugTechnologyPlatformsMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="dei:LegalEntityAxis">CLSN:IPRAndDDrugTechnologyPlatformsMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2020-01-01</xbrli:startDate>
        <xbrli:endDate>2020-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2019-01-01to2019-12-31_custom_GlioblastomaMultiformeBrainCancerMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:ContingentConsiderationByTypeAxis">CLSN:GlioblastomaMultiformeBrainCancerMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2019-01-01</xbrli:startDate>
        <xbrli:endDate>2019-12-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2020-09-29to2020-09-30_custom_EGENIncMember_custom_GlioblastomaMultiformeBrainCancerMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:BusinessAcquisitionAxis">CLSN:EGENIncMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:ContingentConsiderationByTypeAxis">CLSN:GlioblastomaMultiformeBrainCancerMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2020-09-29</xbrli:startDate>
        <xbrli:endDate>2020-09-30</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2020-01-01to2020-03-31_custom_EGENIncMember_custom_PurchaseAgreementMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:BusinessAcquisitionAxis">CLSN:EGENIncMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:PurchaseAgreementMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2020-01-01</xbrli:startDate>
        <xbrli:endDate>2020-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2018-06-27_custom_InitialHorizonCreditAgreementMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:InitialHorizonCreditAgreementMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2018-06-27</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2019-12-31_us-gaap_CommonStockMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:CommonStockMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2019-12-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2019-12-31_us-gaap_AdditionalPaidInCapitalMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:AdditionalPaidInCapitalMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2019-12-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2019-12-31_us-gaap_TreasuryStockMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:TreasuryStockMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2019-12-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2019-12-31_us-gaap_AccumulatedOtherComprehensiveIncomeMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:AccumulatedOtherComprehensiveIncomeMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2019-12-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2019-12-31_us-gaap_RetainedEarningsMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:RetainedEarningsMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2019-12-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-12-31_us-gaap_CommonStockMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:CommonStockMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-12-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-12-31_us-gaap_AdditionalPaidInCapitalMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:AdditionalPaidInCapitalMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-12-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-12-31_us-gaap_TreasuryStockMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:TreasuryStockMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-12-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-12-31_us-gaap_AccumulatedOtherComprehensiveIncomeMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:AccumulatedOtherComprehensiveIncomeMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-12-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-12-31_us-gaap_RetainedEarningsMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:RetainedEarningsMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-12-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-03-31">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2020-01-01to2020-03-31_us-gaap_CommonStockMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:CommonStockMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2020-01-01</xbrli:startDate>
        <xbrli:endDate>2020-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-01-01to2021-03-31_us-gaap_CommonStockMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:CommonStockMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-01</xbrli:startDate>
        <xbrli:endDate>2021-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-03-31_us-gaap_CommonStockMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:CommonStockMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-03-31_us-gaap_CommonStockMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:CommonStockMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2020-01-01to2020-03-31_us-gaap_AdditionalPaidInCapitalMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:AdditionalPaidInCapitalMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2020-01-01</xbrli:startDate>
        <xbrli:endDate>2020-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-01-01to2021-03-31_us-gaap_AdditionalPaidInCapitalMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:AdditionalPaidInCapitalMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-01</xbrli:startDate>
        <xbrli:endDate>2021-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-03-31_us-gaap_AdditionalPaidInCapitalMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:AdditionalPaidInCapitalMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-03-31_us-gaap_AdditionalPaidInCapitalMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:AdditionalPaidInCapitalMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-03-31_us-gaap_TreasuryStockMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:TreasuryStockMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-03-31_us-gaap_TreasuryStockMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:TreasuryStockMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2020-01-01to2020-03-31_us-gaap_AccumulatedOtherComprehensiveIncomeMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:AccumulatedOtherComprehensiveIncomeMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2020-01-01</xbrli:startDate>
        <xbrli:endDate>2020-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-01-01to2021-03-31_us-gaap_AccumulatedOtherComprehensiveIncomeMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:AccumulatedOtherComprehensiveIncomeMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-01</xbrli:startDate>
        <xbrli:endDate>2021-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-03-31_us-gaap_AccumulatedOtherComprehensiveIncomeMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:AccumulatedOtherComprehensiveIncomeMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-03-31_us-gaap_AccumulatedOtherComprehensiveIncomeMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:AccumulatedOtherComprehensiveIncomeMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2020-01-01to2020-03-31_us-gaap_RetainedEarningsMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:RetainedEarningsMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2020-01-01</xbrli:startDate>
        <xbrli:endDate>2020-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-01-01to2021-03-31_us-gaap_RetainedEarningsMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:RetainedEarningsMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-01</xbrli:startDate>
        <xbrli:endDate>2021-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-03-31_us-gaap_RetainedEarningsMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:RetainedEarningsMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-03-31_us-gaap_RetainedEarningsMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:RetainedEarningsMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2019-12-31">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2019-12-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-03-31_custom_IPRAndDMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByAssetClassAxis">CLSN:IPRAndDMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-03-31_us-gaap_GoodwillMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByAssetClassAxis">us-gaap:GoodwillMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-03-31_us-gaap_NoncompeteAgreementsMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:FiniteLivedIntangibleAssetsByMajorClassAxis">us-gaap:NoncompeteAgreementsMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2020-01-01to2020-03-31_us-gaap_TreasuryStockMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:TreasuryStockMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2020-01-01</xbrli:startDate>
        <xbrli:endDate>2020-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-01-01to2021-03-31_us-gaap_TreasuryStockMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:TreasuryStockMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-01</xbrli:startDate>
        <xbrli:endDate>2021-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2018-01-01to2018-12-31_custom_NJMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="srt:StatementGeographicalAxis">CLSN:NJMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2018-01-01</xbrli:startDate>
        <xbrli:endDate>2018-12-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2019-01-01to2019-12-31_custom_NJMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="srt:StatementGeographicalAxis">CLSN:NJMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2019-01-01</xbrli:startDate>
        <xbrli:endDate>2019-12-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2020-09-01to2020-09-30_custom_NJMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="srt:StatementGeographicalAxis">CLSN:NJMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2020-09-01</xbrli:startDate>
        <xbrli:endDate>2020-09-30</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-05-09to2021-05-10_custom_NJMember_srt_MinimumMember_us-gaap_SubsequentEventMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:SubsequentEventTypeAxis">us-gaap:SubsequentEventMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="srt:StatementGeographicalAxis">CLSN:NJMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="srt:RangeAxis">srt:MinimumMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-05-09</xbrli:startDate>
        <xbrli:endDate>2021-05-10</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-05-09to2021-05-10_us-gaap_SubsequentEventMember_custom_NJMember_srt_MaximumMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:SubsequentEventTypeAxis">us-gaap:SubsequentEventMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="srt:StatementGeographicalAxis">CLSN:NJMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="srt:RangeAxis">srt:MaximumMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-05-09</xbrli:startDate>
        <xbrli:endDate>2021-05-10</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2018-06-01to2018-06-30_custom_HorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:HorizonCreditAgreementMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="dei:LegalEntityAxis">CLSN:HorizonTechnologyFinanceCorporationMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2018-06-01</xbrli:startDate>
        <xbrli:endDate>2018-06-30</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2018-06-30_custom_HorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember_us-gaap_LondonInterbankOfferedRateLIBORMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:HorizonCreditAgreementMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="dei:LegalEntityAxis">CLSN:HorizonTechnologyFinanceCorporationMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:VariableRateAxis">us-gaap:LondonInterbankOfferedRateLIBORMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2018-06-30</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-08-28_custom_HorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:HorizonCreditAgreementMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="dei:LegalEntityAxis">CLSN:HorizonTechnologyFinanceCorporationMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-08-28</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-03-17to2021-03-19_custom_CapitalOnDemandTMSalesAgreementMember_custom_JonesTradingInstitutionalServicesLLCMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:CapitalOnDemandTMSalesAgreementMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="dei:LegalEntityAxis">CLSN:JonesTradingInstitutionalServicesLLCMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-03-17</xbrli:startDate>
        <xbrli:endDate>2021-03-19</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-01-31_custom_CapitalOnDemandTMSalesAgreementMember_custom_JonesTradingInstitutionalServicesLLCMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:CapitalOnDemandTMSalesAgreementMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="dei:LegalEntityAxis">CLSN:JonesTradingInstitutionalServicesLLCMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-01-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-01-01to2021-01-31_custom_CapitalOnDemandTMSalesAgreementMember_custom_JonesTradingInstitutionalServicesLLCMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:CapitalOnDemandTMSalesAgreementMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="dei:LegalEntityAxis">CLSN:JonesTradingInstitutionalServicesLLCMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-01</xbrli:startDate>
        <xbrli:endDate>2021-01-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-03-31_us-gaap_CorporateDebtSecuritiesMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:FinancialInstrumentAxis">us-gaap:CorporateDebtSecuritiesMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-12-31_us-gaap_CorporateDebtSecuritiesMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:FinancialInstrumentAxis">us-gaap:CorporateDebtSecuritiesMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-12-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-03-31_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_FairValueInputsLevel2Member_us-gaap_CorporateDebtSecuritiesMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByMeasurementFrequencyAxis">us-gaap:FairValueMeasurementsRecurringMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByFairValueHierarchyLevelAxis">us-gaap:FairValueInputsLevel2Member</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:FinancialInstrumentAxis">us-gaap:CorporateDebtSecuritiesMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-03-31_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_FairValueInputsLevel2Member">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByMeasurementFrequencyAxis">us-gaap:FairValueMeasurementsRecurringMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByFairValueHierarchyLevelAxis">us-gaap:FairValueInputsLevel2Member</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-03-31_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_FairValueInputsLevel1Member">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByMeasurementFrequencyAxis">us-gaap:FairValueMeasurementsRecurringMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByFairValueHierarchyLevelAxis">us-gaap:FairValueInputsLevel1Member</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-03-31_us-gaap_FairValueMeasurementsRecurringMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByMeasurementFrequencyAxis">us-gaap:FairValueMeasurementsRecurringMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-03-31_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_FairValueInputsLevel3Member_us-gaap_CorporateDebtSecuritiesMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByMeasurementFrequencyAxis">us-gaap:FairValueMeasurementsRecurringMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByFairValueHierarchyLevelAxis">us-gaap:FairValueInputsLevel3Member</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:FinancialInstrumentAxis">us-gaap:CorporateDebtSecuritiesMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-03-31_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_FairValueInputsLevel3Member">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByMeasurementFrequencyAxis">us-gaap:FairValueMeasurementsRecurringMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByFairValueHierarchyLevelAxis">us-gaap:FairValueInputsLevel3Member</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-03-31_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_FairValueInputsLevel1Member_us-gaap_CorporateDebtSecuritiesMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByMeasurementFrequencyAxis">us-gaap:FairValueMeasurementsRecurringMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByFairValueHierarchyLevelAxis">us-gaap:FairValueInputsLevel1Member</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:FinancialInstrumentAxis">us-gaap:CorporateDebtSecuritiesMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-03-31_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_CorporateDebtSecuritiesMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByMeasurementFrequencyAxis">us-gaap:FairValueMeasurementsRecurringMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:FinancialInstrumentAxis">us-gaap:CorporateDebtSecuritiesMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-12-31_us-gaap_FairValueMeasurementsRecurringMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByMeasurementFrequencyAxis">us-gaap:FairValueMeasurementsRecurringMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-12-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-12-31_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_FairValueInputsLevel1Member">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByMeasurementFrequencyAxis">us-gaap:FairValueMeasurementsRecurringMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByFairValueHierarchyLevelAxis">us-gaap:FairValueInputsLevel1Member</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-12-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-12-31_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_FairValueInputsLevel2Member">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByMeasurementFrequencyAxis">us-gaap:FairValueMeasurementsRecurringMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByFairValueHierarchyLevelAxis">us-gaap:FairValueInputsLevel2Member</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-12-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-12-31_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_FairValueInputsLevel3Member">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByMeasurementFrequencyAxis">us-gaap:FairValueMeasurementsRecurringMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByFairValueHierarchyLevelAxis">us-gaap:FairValueInputsLevel3Member</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-12-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2018-09-01to2018-09-30">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2018-09-01</xbrli:startDate>
        <xbrli:endDate>2018-09-30</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2018-12-02to2018-12-04_custom_CapitalOnDemandTMSalesAgreementMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:CapitalOnDemandTMSalesAgreementMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2018-12-02</xbrli:startDate>
        <xbrli:endDate>2018-12-04</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2020-01-01to2020-12-31_custom_CapitalOnDemandAgreementMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:CapitalOnDemandAgreementMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2020-01-01</xbrli:startDate>
        <xbrli:endDate>2020-12-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2020-02-26to2020-02-27_custom_SecuritiesPurchaseAgreementMember_us-gaap_SubsequentEventMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:SecuritiesPurchaseAgreementMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2020-02-26</xbrli:startDate>
        <xbrli:endDate>2020-02-27</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-02-27_us-gaap_SubsequentEventMember_custom_SecuritiesPurchaseAgreementMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:SecuritiesPurchaseAgreementMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-02-27</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-02-27_us-gaap_SubsequentEventMember_custom_SecuritiesPurchaseAgreementMember_custom_OriginalWarrantsMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:SecuritiesPurchaseAgreementMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">CLSN:OriginalWarrantsMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-02-27</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-03-12_custom_ExchangeAgreementsMember_us-gaap_WarrantMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:ExchangeAgreementsMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:WarrantMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-03-12</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2020-06-21to2020-06-22_custom_UnderwritingAgreementMember_custom_UnderwrittenOfferingMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:UnderwritingAgreementMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:SubsidiarySaleOfStockAxis">CLSN:UnderwrittenOfferingMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2020-06-21</xbrli:startDate>
        <xbrli:endDate>2020-06-22</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-06-22_custom_UnderwritingAgreementMember_custom_UnderwrittenOfferingMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:UnderwritingAgreementMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:SubsidiarySaleOfStockAxis">CLSN:UnderwrittenOfferingMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-06-22</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2020-09-07to2020-09-08_custom_LPCPurchaseAgreementMember_custom_LincolnParkCapitalFundLLCMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:LPCPurchaseAgreementMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="dei:LegalEntityAxis">CLSN:LincolnParkCapitalFundLLCMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2020-09-07</xbrli:startDate>
        <xbrli:endDate>2020-09-08</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2020-09-07to2020-09-08_custom_LPCPurchaseAgreementMember_custom_LincolnParkCapitalFundLLCMember_custom_LPCCommitmentSharesMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:LPCPurchaseAgreementMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="dei:LegalEntityAxis">CLSN:LincolnParkCapitalFundLLCMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">CLSN:LPCCommitmentSharesMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2020-09-07</xbrli:startDate>
        <xbrli:endDate>2020-09-08</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-03-18to2021-03-19">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-03-18</xbrli:startDate>
        <xbrli:endDate>2021-03-19</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-01-01to2021-03-31_custom_CapitalOnDemandAgreementMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:CapitalOnDemandAgreementMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-01</xbrli:startDate>
        <xbrli:endDate>2021-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-03-31_srt_ScenarioForecastMember_custom_ExchangeAgreementsMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:ExchangeAgreementsMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-01-01to2021-03-31_srt_ScenarioForecastMember_custom_ExchangeAgreementsMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:ExchangeAgreementsMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-01</xbrli:startDate>
        <xbrli:endDate>2021-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-01-21to2021-01-22_custom_UnderwritingAgreementMember_custom_JanuaryRegisteredDirectOfferingMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:UnderwritingAgreementMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:SubsidiarySaleOfStockAxis">CLSN:JanuaryRegisteredDirectOfferingMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-21</xbrli:startDate>
        <xbrli:endDate>2021-01-22</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-01-22_custom_UnderwritingAgreementMember_custom_JanuaryRegisteredDirectOfferingMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:UnderwritingAgreementMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:SubsidiarySaleOfStockAxis">CLSN:JanuaryRegisteredDirectOfferingMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-01-22</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-03-30to2021-03-31_custom_UnderwritingAgreementMember_custom_MarchRegisteredDirectOfferingMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:UnderwritingAgreementMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:SubsidiarySaleOfStockAxis">CLSN:MarchRegisteredDirectOfferingMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-03-30</xbrli:startDate>
        <xbrli:endDate>2021-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-03-31_custom_UnderwritingAgreementMember_custom_MarchRegisteredDirectOfferingMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:UnderwritingAgreementMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:SubsidiarySaleOfStockAxis">CLSN:MarchRegisteredDirectOfferingMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2020-01-01to2020-12-31_custom_LPCPurchaseAgreementMember_custom_LincolnParkCapitalFundLLCMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:LPCPurchaseAgreementMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="dei:LegalEntityAxis">CLSN:LincolnParkCapitalFundLLCMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2020-01-01</xbrli:startDate>
        <xbrli:endDate>2020-12-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-03-31_custom_TwoThousandAndEighteenStockIncentivePlanMember_srt_MinimumMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:PlanNameAxis">CLSN:TwoThousandAndEighteenStockIncentivePlanMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="srt:RangeAxis">srt:MinimumMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-03-31_custom_TwoThousandAndEighteenStockIncentivePlanMember_srt_MaximumMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:PlanNameAxis">CLSN:TwoThousandAndEighteenStockIncentivePlanMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="srt:RangeAxis">srt:MaximumMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-06-15_custom_TwoThousandAndEighteenStockIncentivePlanMember_srt_MinimumMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:PlanNameAxis">CLSN:TwoThousandAndEighteenStockIncentivePlanMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="srt:RangeAxis">srt:MinimumMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-06-15</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-06-15_custom_TwoThousandAndEighteenStockIncentivePlanMember_srt_MaximumMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:PlanNameAxis">CLSN:TwoThousandAndEighteenStockIncentivePlanMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="srt:RangeAxis">srt:MaximumMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-06-15</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-01-01to2021-03-31_custom_TwoThousandSevenStockIncentivePlanMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:PlanNameAxis">CLSN:TwoThousandSevenStockIncentivePlanMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-01</xbrli:startDate>
        <xbrli:endDate>2021-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2018-09-28_custom_InducementOptionGrantsMember_custom_FiveNewEmployeesMember_us-gaap_CommonStockMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:PlanNameAxis">CLSN:InducementOptionGrantsMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="srt:TitleOfIndividualAxis">CLSN:FiveNewEmployeesMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:CommonStockMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2018-09-28</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2019-02-19_custom_InducementOptionGrantsMember_custom_FiveNewEmployeesMember_us-gaap_CommonStockMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:PlanNameAxis">CLSN:InducementOptionGrantsMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="srt:TitleOfIndividualAxis">CLSN:FiveNewEmployeesMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:StatementEquityComponentsAxis">us-gaap:CommonStockMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2019-02-19</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2018-09-28_custom_InducementOptionGrantsMember_custom_FiveNewEmployeesMember_us-gaap_RestrictedStockMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:PlanNameAxis">CLSN:InducementOptionGrantsMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="srt:TitleOfIndividualAxis">CLSN:FiveNewEmployeesMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:AwardTypeAxis">us-gaap:RestrictedStockMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2018-09-28</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2019-02-19_custom_InducementOptionGrantsMember_custom_FiveNewEmployeesMember_us-gaap_RestrictedStockMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:PlanNameAxis">CLSN:InducementOptionGrantsMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="srt:TitleOfIndividualAxis">CLSN:FiveNewEmployeesMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:AwardTypeAxis">us-gaap:RestrictedStockMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2019-02-19</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2018-09-27to2018-09-28_custom_InducementOptionGrantsMember_custom_FiveNewEmployeesMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:PlanNameAxis">CLSN:InducementOptionGrantsMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="srt:TitleOfIndividualAxis">CLSN:FiveNewEmployeesMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2018-09-27</xbrli:startDate>
        <xbrli:endDate>2018-09-28</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2019-02-18to2019-02-19_custom_InducementOptionGrantsMember_custom_FiveNewEmployeesMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:PlanNameAxis">CLSN:InducementOptionGrantsMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="srt:TitleOfIndividualAxis">CLSN:FiveNewEmployeesMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2019-02-18</xbrli:startDate>
        <xbrli:endDate>2019-02-19</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-03-31_custom_EquityStockAwardsMember_custom_GrantedUnderTwoThousandEighteenPlanAndTwoThousandSevenPlanMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:AwardTypeAxis">CLSN:EquityStockAwardsMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="srt:StatementScenarioAxis">CLSN:GrantedUnderTwoThousandEighteenPlanAndTwoThousandSevenPlanMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-12-31_custom_TwoThousandAndEighteenPlanMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:PlanNameAxis">CLSN:TwoThousandAndEighteenPlanMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-12-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-12-31_custom_InducementAwardsMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:AwardTypeAxis">CLSN:InducementAwardsMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-12-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-03-31_custom_TwoThousandAndEighteenStockIncentivePlanMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:PlanNameAxis">CLSN:TwoThousandAndEighteenStockIncentivePlanMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-01-01to2021-03-31_custom_EmployeeStockOptionAndRestrictedStockAwardsMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:AwardTypeAxis">CLSN:EmployeeStockOptionAndRestrictedStockAwardsMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-01</xbrli:startDate>
        <xbrli:endDate>2021-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2020-01-01to2020-03-31_custom_EmployeeStockOptionAndRestrictedStockAwardsMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:AwardTypeAxis">CLSN:EmployeeStockOptionAndRestrictedStockAwardsMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2020-01-01</xbrli:startDate>
        <xbrli:endDate>2020-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-01-01to2021-03-31_custom_EmployeeStockOptionAndRestrictedStockAwardsMember_us-gaap_ResearchAndDevelopmentExpenseMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:AwardTypeAxis">CLSN:EmployeeStockOptionAndRestrictedStockAwardsMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:IncomeStatementLocationAxis">us-gaap:ResearchAndDevelopmentExpenseMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-01</xbrli:startDate>
        <xbrli:endDate>2021-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2020-01-01to2020-03-31_custom_EmployeeStockOptionAndRestrictedStockAwardsMember_us-gaap_ResearchAndDevelopmentExpenseMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:AwardTypeAxis">CLSN:EmployeeStockOptionAndRestrictedStockAwardsMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:IncomeStatementLocationAxis">us-gaap:ResearchAndDevelopmentExpenseMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2020-01-01</xbrli:startDate>
        <xbrli:endDate>2020-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-01-01to2021-03-31_custom_EmployeeStockOptionAndRestrictedStockAwardsMember_us-gaap_GeneralAndAdministrativeExpenseMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:AwardTypeAxis">CLSN:EmployeeStockOptionAndRestrictedStockAwardsMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:IncomeStatementLocationAxis">us-gaap:GeneralAndAdministrativeExpenseMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-01</xbrli:startDate>
        <xbrli:endDate>2021-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2020-01-01to2020-03-31_custom_EmployeeStockOptionAndRestrictedStockAwardsMember_us-gaap_GeneralAndAdministrativeExpenseMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:AwardTypeAxis">CLSN:EmployeeStockOptionAndRestrictedStockAwardsMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:IncomeStatementLocationAxis">us-gaap:GeneralAndAdministrativeExpenseMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2020-01-01</xbrli:startDate>
        <xbrli:endDate>2020-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-01-01to2021-03-31_us-gaap_RestrictedStockMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:AwardTypeAxis">us-gaap:RestrictedStockMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-01</xbrli:startDate>
        <xbrli:endDate>2021-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-01-01to2021-03-31_us-gaap_EmployeeStockOptionMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:AwardTypeAxis">us-gaap:EmployeeStockOptionMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-01</xbrli:startDate>
        <xbrli:endDate>2021-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-12-31_us-gaap_RestrictedStockMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:AwardTypeAxis">us-gaap:RestrictedStockMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-12-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-03-31_us-gaap_RestrictedStockMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:AwardTypeAxis">us-gaap:RestrictedStockMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2020-01-01to2020-12-31_srt_MinimumMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="srt:RangeAxis">srt:MinimumMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2020-01-01</xbrli:startDate>
        <xbrli:endDate>2020-12-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2020-01-01to2020-12-31_srt_MaximumMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="srt:RangeAxis">srt:MaximumMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2020-01-01</xbrli:startDate>
        <xbrli:endDate>2020-12-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2019-01-01to2019-12-31">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2019-01-01</xbrli:startDate>
        <xbrli:endDate>2019-12-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2019-01-01to2019-12-31_srt_MinimumMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="srt:RangeAxis">srt:MinimumMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2019-01-01</xbrli:startDate>
        <xbrli:endDate>2019-12-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2019-01-01to2019-12-31_srt_MaximumMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="srt:RangeAxis">srt:MaximumMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2019-01-01</xbrli:startDate>
        <xbrli:endDate>2019-12-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-01-01to2021-03-31_srt_MinimumMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="srt:RangeAxis">srt:MinimumMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-01</xbrli:startDate>
        <xbrli:endDate>2021-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-01-01to2021-03-31_srt_MaximumMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="srt:RangeAxis">srt:MaximumMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-01</xbrli:startDate>
        <xbrli:endDate>2021-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2020-01-01to2020-03-31_srt_MinimumMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="srt:RangeAxis">srt:MinimumMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2020-01-01</xbrli:startDate>
        <xbrli:endDate>2020-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2020-01-01to2020-03-31_srt_MaximumMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="srt:RangeAxis">srt:MaximumMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2020-01-01</xbrli:startDate>
        <xbrli:endDate>2020-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2019-03-28_custom_EGENIncMember_custom_AmendedAssetPurchaseAgreementMember_custom_AchievingMilestoneWithInOneYearMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:AmendedAssetPurchaseAgreementMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:RelatedPartyTransactionAxis">CLSN:AchievingMilestoneWithInOneYearMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2019-03-28</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2019-03-28_custom_EGENIncMember_custom_AmendedAssetPurchaseAgreementMember_custom_CertainBusinessDaysOfAchievingMilestoneMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:AmendedAssetPurchaseAgreementMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:RelatedPartyTransactionAxis">CLSN:CertainBusinessDaysOfAchievingMilestoneMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2019-03-28</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2019-03-28_custom_EGENIncMember_custom_AmendedAssetPurchaseAgreementMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:AmendedAssetPurchaseAgreementMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2019-03-28</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-01-01to2021-03-31_custom_EGWCMember_custom_FairValueEarnoutMilestoneLiabilityMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:BusinessAcquisitionAxis">CLSN:EGWCMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:FairValueEarnoutMilestoneLiabilityMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-01</xbrli:startDate>
        <xbrli:endDate>2021-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2020-01-01to2020-12-31_custom_EGWCMember_custom_FairValueEarnoutMilestoneLiabilityMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:BusinessAcquisitionAxis">CLSN:EGWCMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:FairValueEarnoutMilestoneLiabilityMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2020-01-01</xbrli:startDate>
        <xbrli:endDate>2020-12-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-01-01to2021-03-31_custom_EGWCMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:BusinessAcquisitionAxis">CLSN:EGWCMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-01</xbrli:startDate>
        <xbrli:endDate>2021-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2020-01-01to2020-03-31_custom_EGWCMember_custom_FairValueEarnoutMilestoneLiabilityMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:BusinessAcquisitionAxis">CLSN:EGWCMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:FairValueEarnoutMilestoneLiabilityMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2020-01-01</xbrli:startDate>
        <xbrli:endDate>2020-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2019-01-01to2019-12-31_custom_EGWCMember_custom_FairValueEarnoutMilestoneLiabilityMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:BusinessAcquisitionAxis">CLSN:EGWCMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:FairValueEarnoutMilestoneLiabilityMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2019-01-01</xbrli:startDate>
        <xbrli:endDate>2019-12-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2020-01-01to2020-03-31_custom_EGWCMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:BusinessAcquisitionAxis">CLSN:EGWCMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2020-01-01</xbrli:startDate>
        <xbrli:endDate>2020-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2020-01-01to2020-12-31">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2020-01-01</xbrli:startDate>
        <xbrli:endDate>2020-12-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2011-07-31">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2011-07-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2011-07-01to2011-07-31">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2011-07-01</xbrli:startDate>
        <xbrli:endDate>2011-07-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-01-01to2021-03-31_custom_FirstLeaseAmendmentMember_custom_FirstYearMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:FirstLeaseAmendmentMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:AwardTypeAxis">CLSN:FirstYearMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-01</xbrli:startDate>
        <xbrli:endDate>2021-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-01-01to2021-03-31_custom_FirstLeaseAmendmentMember_custom_FinalYearMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:FirstLeaseAmendmentMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:AwardTypeAxis">CLSN:FinalYearMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-01</xbrli:startDate>
        <xbrli:endDate>2021-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-01-01to2021-03-31_custom_SecondLeaseAmendmentMember_custom_FirstYearMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:SecondLeaseAmendmentMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:AwardTypeAxis">CLSN:FirstYearMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-01</xbrli:startDate>
        <xbrli:endDate>2021-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-01-01to2021-03-31_custom_SecondLeaseAmendmentMember_custom_FinalYearMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:SecondLeaseAmendmentMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:AwardTypeAxis">CLSN:FinalYearMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-01</xbrli:startDate>
        <xbrli:endDate>2021-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-12-31_custom_HuntsvilleAlabamaMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="srt:StatementGeographicalAxis">CLSN:HuntsvilleAlabamaMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-12-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2018-01-01to2018-01-31_custom_EGENAssetPurchaseAgreementMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:EGENAssetPurchaseAgreementMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2018-01-01</xbrli:startDate>
        <xbrli:endDate>2018-01-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2019-01-02">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2019-01-02</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2018-12-30to2019-01-02">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2018-12-30</xbrli:startDate>
        <xbrli:endDate>2019-01-02</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2019-01-02_us-gaap_AccountingStandardsUpdate201602Member">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:AdjustmentsForNewAccountingPronouncementsAxis">us-gaap:AccountingStandardsUpdate201602Member</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2019-01-02</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-01-01to2021-03-31_custom_OperatingLeasesMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:OperatingLeasesMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-01-01</xbrli:startDate>
        <xbrli:endDate>2021-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2020-01-01to2020-03-31_custom_OperatingLeasesMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:TypeOfArrangementAxis">CLSN:OperatingLeasesMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2020-01-01</xbrli:startDate>
        <xbrli:endDate>2020-03-31</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2013-01-17to2013-01-18_custom_HisunMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:AccountsNotesLoansAndFinancingReceivablesByLegalEntityOfCounterpartyTypeAxis">CLSN:HisunMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2013-01-17</xbrli:startDate>
        <xbrli:endDate>2013-01-18</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2013-01-18_custom_HisunMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:AccountsNotesLoansAndFinancingReceivablesByLegalEntityOfCounterpartyTypeAxis">CLSN:HisunMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2013-01-18</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2020-04-22to2020-04-24">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2020-04-22</xbrli:startDate>
        <xbrli:endDate>2020-04-24</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2020-10-01to2020-10-02_us-gaap_SubsequentEventMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2020-10-01</xbrli:startDate>
        <xbrli:endDate>2020-10-02</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2021-04-04to2021-04-05_us-gaap_SubsequentEventMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:SubsequentEventTypeAxis">us-gaap:SubsequentEventMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2021-04-04</xbrli:startDate>
        <xbrli:endDate>2021-04-05</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-12-31_us-gaap_EmployeeStockOptionMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:AwardTypeAxis">us-gaap:EmployeeStockOptionMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-12-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-03-31_us-gaap_EmployeeStockOptionMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:AwardTypeAxis">us-gaap:EmployeeStockOptionMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-03-31_us-gaap_FairValueMeasurementsNonrecurringMember_custom_InprocessRandDMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByMeasurementFrequencyAxis">us-gaap:FairValueMeasurementsNonrecurringMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:FinancialInstrumentAxis">CLSN:InprocessRandDMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-03-31_us-gaap_FairValueMeasurementsNonrecurringMember_us-gaap_FairValueInputsLevel1Member_custom_InprocessRandDMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByMeasurementFrequencyAxis">us-gaap:FairValueMeasurementsNonrecurringMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByFairValueHierarchyLevelAxis">us-gaap:FairValueInputsLevel1Member</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:FinancialInstrumentAxis">CLSN:InprocessRandDMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-03-31_us-gaap_FairValueMeasurementsNonrecurringMember_us-gaap_FairValueInputsLevel2Member_custom_InprocessRandDMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByMeasurementFrequencyAxis">us-gaap:FairValueMeasurementsNonrecurringMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByFairValueHierarchyLevelAxis">us-gaap:FairValueInputsLevel2Member</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:FinancialInstrumentAxis">CLSN:InprocessRandDMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2021-03-31_us-gaap_FairValueMeasurementsNonrecurringMember_us-gaap_FairValueInputsLevel3Member_custom_InprocessRandDMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByMeasurementFrequencyAxis">us-gaap:FairValueMeasurementsNonrecurringMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByFairValueHierarchyLevelAxis">us-gaap:FairValueInputsLevel3Member</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:FinancialInstrumentAxis">CLSN:InprocessRandDMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2021-03-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-12-31_us-gaap_FairValueMeasurementsNonrecurringMember_custom_InprocessRandDMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByMeasurementFrequencyAxis">us-gaap:FairValueMeasurementsNonrecurringMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:FinancialInstrumentAxis">CLSN:InprocessRandDMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-12-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-12-31_us-gaap_FairValueMeasurementsNonrecurringMember_us-gaap_FairValueInputsLevel1Member_custom_InprocessRandDMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByMeasurementFrequencyAxis">us-gaap:FairValueMeasurementsNonrecurringMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByFairValueHierarchyLevelAxis">us-gaap:FairValueInputsLevel1Member</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:FinancialInstrumentAxis">CLSN:InprocessRandDMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-12-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-12-31_us-gaap_FairValueMeasurementsNonrecurringMember_us-gaap_FairValueInputsLevel2Member_custom_InprocessRandDMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByMeasurementFrequencyAxis">us-gaap:FairValueMeasurementsNonrecurringMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByFairValueHierarchyLevelAxis">us-gaap:FairValueInputsLevel2Member</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:FinancialInstrumentAxis">CLSN:InprocessRandDMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-12-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="AsOf2020-12-31_us-gaap_FairValueMeasurementsNonrecurringMember_us-gaap_FairValueInputsLevel3Member_custom_InprocessRandDMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByMeasurementFrequencyAxis">us-gaap:FairValueMeasurementsNonrecurringMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:FairValueByFairValueHierarchyLevelAxis">us-gaap:FairValueInputsLevel3Member</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:FinancialInstrumentAxis">CLSN:InprocessRandDMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:instant>2020-12-31</xbrli:instant>
      </xbrli:period>
    </xbrli:context>
    <xbrli:context id="From2020-07-01to2020-09-30_custom_EGENIncMember_custom_GlioblastomaMultiformeBrainCancerMember">
      <xbrli:entity>
        <xbrli:identifier scheme="http://www.sec.gov/CIK">0000749647</xbrli:identifier>
        <xbrli:segment>
          <xbrldi:explicitMember dimension="us-gaap:BusinessAcquisitionAxis">CLSN:EGENIncMember</xbrldi:explicitMember>
          <xbrldi:explicitMember dimension="us-gaap:ContingentConsiderationByTypeAxis">CLSN:GlioblastomaMultiformeBrainCancerMember</xbrldi:explicitMember>
        </xbrli:segment>
      </xbrli:entity>
      <xbrli:period>
        <xbrli:startDate>2020-07-01</xbrli:startDate>
        <xbrli:endDate>2020-09-30</xbrli:endDate>
      </xbrli:period>
    </xbrli:context>
    <xbrli:unit id="USD">
      <xbrli:measure>iso4217:USD</xbrli:measure>
    </xbrli:unit>
    <xbrli:unit id="Shares">
      <xbrli:measure>xbrli:shares</xbrli:measure>
    </xbrli:unit>
    <xbrli:unit id="USDPShares">
      <xbrli:divide>
        <xbrli:unitNumerator>
          <xbrli:measure>iso4217:USD</xbrli:measure>
        </xbrli:unitNumerator>
        <xbrli:unitDenominator>
          <xbrli:measure>xbrli:shares</xbrli:measure>
        </xbrli:unitDenominator>
      </xbrli:divide>
    </xbrli:unit>
    <xbrli:unit id="Percentage">
      <xbrli:measure>xbrli:pure</xbrli:measure>
    </xbrli:unit>
    <xbrli:unit id="Sqft">
      <xbrli:measure>utr:sqft</xbrli:measure>
    </xbrli:unit>
    <us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">15000045</us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent>
    <us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent contextRef="AsOf2020-12-31" unitRef="USD" xsi:nil="true" />
    <us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent contextRef="AsOf2021-03-31_us-gaap_CorporateDebtSecuritiesMember" unitRef="USD" decimals="0">15000045</us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent>
    <us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent contextRef="AsOf2020-12-31_us-gaap_CorporateDebtSecuritiesMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent contextRef="AsOf2021-03-31_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_FairValueInputsLevel2Member_us-gaap_CorporateDebtSecuritiesMember" unitRef="USD" decimals="0">15000045</us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent>
    <us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent contextRef="AsOf2021-03-31_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_FairValueInputsLevel3Member_us-gaap_CorporateDebtSecuritiesMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent contextRef="AsOf2021-03-31_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_FairValueInputsLevel1Member_us-gaap_CorporateDebtSecuritiesMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent contextRef="AsOf2021-03-31_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_CorporateDebtSecuritiesMember" unitRef="USD" decimals="0">15000045</us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent>
    <us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent contextRef="AsOf2021-03-31_us-gaap_FairValueMeasurementsNonrecurringMember_custom_InprocessRandDMember" unitRef="USD" decimals="0">13366234</us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent>
    <us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent contextRef="AsOf2021-03-31_us-gaap_FairValueMeasurementsNonrecurringMember_us-gaap_FairValueInputsLevel1Member_custom_InprocessRandDMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent contextRef="AsOf2021-03-31_us-gaap_FairValueMeasurementsNonrecurringMember_us-gaap_FairValueInputsLevel2Member_custom_InprocessRandDMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent contextRef="AsOf2021-03-31_us-gaap_FairValueMeasurementsNonrecurringMember_us-gaap_FairValueInputsLevel3Member_custom_InprocessRandDMember" unitRef="USD" decimals="0">13366234</us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent>
    <us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent contextRef="AsOf2020-12-31_us-gaap_FairValueMeasurementsNonrecurringMember_custom_InprocessRandDMember" unitRef="USD" decimals="0">13366234</us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent>
    <us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent contextRef="AsOf2020-12-31_us-gaap_FairValueMeasurementsNonrecurringMember_us-gaap_FairValueInputsLevel1Member_custom_InprocessRandDMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent contextRef="AsOf2020-12-31_us-gaap_FairValueMeasurementsNonrecurringMember_us-gaap_FairValueInputsLevel2Member_custom_InprocessRandDMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent contextRef="AsOf2020-12-31_us-gaap_FairValueMeasurementsNonrecurringMember_us-gaap_FairValueInputsLevel3Member_custom_InprocessRandDMember" unitRef="USD" decimals="0">13366234</us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent>
    <us-gaap:FiniteLivedIntangibleAssetsNet contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">56831</us-gaap:FiniteLivedIntangibleAssetsNet>
    <us-gaap:FiniteLivedIntangibleAssetsNet contextRef="AsOf2020-12-31_custom_AspirePurchaseAgreementsMember" unitRef="USD" decimals="0">113660</us-gaap:FiniteLivedIntangibleAssetsNet>
    <us-gaap:FiniteLivedIntangibleAssetsNet contextRef="AsOf2021-03-31_custom_EGENIncMember_custom_PurchaseAgreementMember" unitRef="USD" decimals="0">56831</us-gaap:FiniteLivedIntangibleAssetsNet>
    <us-gaap:FiniteLivedIntangibleAssetsNet contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">113660</us-gaap:FiniteLivedIntangibleAssetsNet>
    <us-gaap:FiniteLivedIntangibleAssetsNet contextRef="AsOf2020-12-31_us-gaap_NoncompeteAgreementsMember" unitRef="USD" decimals="0">113660</us-gaap:FiniteLivedIntangibleAssetsNet>
    <us-gaap:FiniteLivedIntangibleAssetsNet contextRef="AsOf2020-12-31_custom_IPRAndDMember" unitRef="USD" decimals="0">13366234</us-gaap:FiniteLivedIntangibleAssetsNet>
    <us-gaap:FiniteLivedIntangibleAssetsNet contextRef="AsOf2020-12-31_us-gaap_GoodwillMember" unitRef="USD" decimals="0">1976101</us-gaap:FiniteLivedIntangibleAssetsNet>
    <us-gaap:FiniteLivedIntangibleAssetsNet contextRef="AsOf2021-03-31_custom_IPRAndDMember" unitRef="USD" decimals="0">13366234</us-gaap:FiniteLivedIntangibleAssetsNet>
    <us-gaap:FiniteLivedIntangibleAssetsNet contextRef="AsOf2021-03-31_us-gaap_GoodwillMember" unitRef="USD" decimals="0">1976101</us-gaap:FiniteLivedIntangibleAssetsNet>
    <us-gaap:FiniteLivedIntangibleAssetsNet contextRef="AsOf2021-03-31_us-gaap_NoncompeteAgreementsMember" unitRef="USD" decimals="0">56831</us-gaap:FiniteLivedIntangibleAssetsNet>
    <us-gaap:BusinessCombinationContingentConsiderationLiabilityNoncurrent contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">7169000</us-gaap:BusinessCombinationContingentConsiderationLiabilityNoncurrent>
    <us-gaap:BusinessCombinationContingentConsiderationLiabilityNoncurrent contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">7018000</us-gaap:BusinessCombinationContingentConsiderationLiabilityNoncurrent>
    <us-gaap:BusinessCombinationContingentConsiderationLiabilityNoncurrent contextRef="AsOf2021-03-31_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_FairValueInputsLevel2Member" unitRef="USD" xsi:nil="true" />
    <us-gaap:BusinessCombinationContingentConsiderationLiabilityNoncurrent contextRef="AsOf2021-03-31_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_FairValueInputsLevel1Member" unitRef="USD" xsi:nil="true" />
    <us-gaap:BusinessCombinationContingentConsiderationLiabilityNoncurrent contextRef="AsOf2021-03-31_us-gaap_FairValueMeasurementsRecurringMember" unitRef="USD" decimals="0">7169000</us-gaap:BusinessCombinationContingentConsiderationLiabilityNoncurrent>
    <us-gaap:BusinessCombinationContingentConsiderationLiabilityNoncurrent contextRef="AsOf2021-03-31_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_FairValueInputsLevel3Member" unitRef="USD" decimals="0">7169000</us-gaap:BusinessCombinationContingentConsiderationLiabilityNoncurrent>
    <us-gaap:BusinessCombinationContingentConsiderationLiabilityNoncurrent contextRef="AsOf2020-12-31_us-gaap_FairValueMeasurementsRecurringMember" unitRef="USD" decimals="0">7018000</us-gaap:BusinessCombinationContingentConsiderationLiabilityNoncurrent>
    <us-gaap:BusinessCombinationContingentConsiderationLiabilityNoncurrent contextRef="AsOf2020-12-31_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_FairValueInputsLevel1Member" unitRef="USD" xsi:nil="true" />
    <us-gaap:BusinessCombinationContingentConsiderationLiabilityNoncurrent contextRef="AsOf2020-12-31_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_FairValueInputsLevel2Member" unitRef="USD" xsi:nil="true" />
    <us-gaap:BusinessCombinationContingentConsiderationLiabilityNoncurrent contextRef="AsOf2020-12-31_us-gaap_FairValueMeasurementsRecurringMember_us-gaap_FairValueInputsLevel3Member" unitRef="USD" decimals="0">7018000</us-gaap:BusinessCombinationContingentConsiderationLiabilityNoncurrent>
    <us-gaap:AssetImpairmentCharges contextRef="From2018-01-01to2018-12-31_custom_EGENIncMember" unitRef="USD" decimals="0">7000000</us-gaap:AssetImpairmentCharges>
    <us-gaap:AssetImpairmentCharges contextRef="From2018-01-01to2018-12-31_custom_EGENIncMember_custom_GlioblastomaMultiformeBrainCancerMember" unitRef="USD" decimals="0">9400000</us-gaap:AssetImpairmentCharges>
    <us-gaap:AssetImpairmentCharges contextRef="From2021-01-01to2021-03-31_custom_IPRAndDDrugTechnologyPlatformsMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:AssetImpairmentCharges contextRef="From2020-01-01to2020-03-31_custom_IPRAndDDrugTechnologyPlatformsMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:AssetImpairmentCharges contextRef="From2019-01-01to2019-12-31_custom_GlioblastomaMultiformeBrainCancerMember" unitRef="USD" decimals="0">2400000</us-gaap:AssetImpairmentCharges>
    <us-gaap:AssetImpairmentCharges contextRef="From2020-09-29to2020-09-30_custom_EGENIncMember_custom_GlioblastomaMultiformeBrainCancerMember" unitRef="USD" decimals="0">2400000</us-gaap:AssetImpairmentCharges>
    <us-gaap:FiniteLivedIntangibleAssetUsefulLife contextRef="From2021-01-01to2021-03-31_custom_EGENIncMember_custom_PurchaseAgreementMember">P7Y</us-gaap:FiniteLivedIntangibleAssetUsefulLife>
    <us-gaap:FinitelivedIntangibleAssetsAcquired1 contextRef="From2021-01-01to2021-03-31_custom_IPRAndDDrugTechnologyPlatformsMember_custom_OvarianCancerMember" unitRef="USD" decimals="0">13300000</us-gaap:FinitelivedIntangibleAssetsAcquired1>
    <us-gaap:FinitelivedIntangibleAssetsAcquired1 contextRef="From2021-01-01to2021-03-31_custom_EGENIncMember_custom_PurchaseAgreementMember" unitRef="USD" decimals="0">1600000</us-gaap:FinitelivedIntangibleAssetsAcquired1>
    <us-gaap:FiniteLivedIntangibleAssetsAccumulatedAmortization contextRef="AsOf2020-12-31_custom_AspirePurchaseAgreementsMember" unitRef="USD" decimals="0">1477554</us-gaap:FiniteLivedIntangibleAssetsAccumulatedAmortization>
    <us-gaap:FiniteLivedIntangibleAssetsAccumulatedAmortization contextRef="AsOf2021-03-31_custom_EGENIncMember_custom_PurchaseAgreementMember" unitRef="USD" decimals="0">1534383</us-gaap:FiniteLivedIntangibleAssetsAccumulatedAmortization>
    <us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1 contextRef="AsOf2021-03-31" unitRef="USDPShares" decimals="INF">0.01</us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1>
    <us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1 contextRef="AsOf2020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember_us-gaap_CommonStockMember" unitRef="USDPShares" decimals="INF">1.01</us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1>
    <us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1 contextRef="AsOf2018-06-27_custom_InitialHorizonCreditAgreementMember_us-gaap_CommonStockMember" unitRef="USDPShares" decimals="INF">2.63</us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1>
    <us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1 contextRef="AsOf2020-02-27_us-gaap_SubsequentEventMember_custom_SecuritiesPurchaseAgreementMember_custom_OriginalWarrantsMember" unitRef="USDPShares" decimals="INF">1.15</us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1>
    <us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1 contextRef="AsOf2020-03-12_custom_ExchangeAgreementsMember_us-gaap_WarrantMember" unitRef="USDPShares" decimals="INF">1.24</us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1>
    <us-gaap:ProceedsFromIssuanceOfCommonStock contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">38943478</us-gaap:ProceedsFromIssuanceOfCommonStock>
    <us-gaap:ProceedsFromIssuanceOfCommonStock contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">5794747</us-gaap:ProceedsFromIssuanceOfCommonStock>
    <us-gaap:ProceedsFromIssuanceOfCommonStock contextRef="From2020-01-01to2020-12-31_custom_CapitalOnDemandAgreementMember" unitRef="USD" decimals="0">6200000</us-gaap:ProceedsFromIssuanceOfCommonStock>
    <us-gaap:ProceedsFromIssuanceOfCommonStock contextRef="From2020-02-26to2020-02-27_custom_SecuritiesPurchaseAgreementMember_us-gaap_SubsequentEventMember" unitRef="USD" decimals="0">4800000</us-gaap:ProceedsFromIssuanceOfCommonStock>
    <us-gaap:ProceedsFromIssuanceOfCommonStock contextRef="From2020-06-21to2020-06-22_custom_UnderwritingAgreementMember_custom_UnderwrittenOfferingMember" unitRef="USD" decimals="0">9100000</us-gaap:ProceedsFromIssuanceOfCommonStock>
    <us-gaap:ProceedsFromIssuanceOfCommonStock contextRef="From2021-01-01to2021-03-31_custom_CapitalOnDemandAgreementMember" unitRef="USD" decimals="0">6900000</us-gaap:ProceedsFromIssuanceOfCommonStock>
    <us-gaap:ProceedsFromIssuanceOfCommonStock contextRef="From2021-01-21to2021-01-22_custom_UnderwritingAgreementMember_custom_JanuaryRegisteredDirectOfferingMember" unitRef="USD" decimals="0">35000000</us-gaap:ProceedsFromIssuanceOfCommonStock>
    <us-gaap:ProceedsFromIssuanceOfCommonStock contextRef="From2021-03-30to2021-03-31_custom_UnderwritingAgreementMember_custom_MarchRegisteredDirectOfferingMember" unitRef="USD" decimals="0">15000000</us-gaap:ProceedsFromIssuanceOfCommonStock>
    <us-gaap:ProceedsFromIssuanceOfCommonStock contextRef="From2020-01-01to2020-12-31_custom_LPCPurchaseAgreementMember_custom_LincolnParkCapitalFundLLCMember" unitRef="USD" decimals="0">2200000</us-gaap:ProceedsFromIssuanceOfCommonStock>
    <us-gaap:IndefinitelivedIntangibleAssetsAcquired contextRef="From2021-01-01to2021-03-31_custom_EGENIncMember_custom_IPRAndDDrugTechnologyPlatformsMember" unitRef="USD" decimals="0">24200000</us-gaap:IndefinitelivedIntangibleAssetsAcquired>
    <us-gaap:GoodwillAcquiredDuringPeriod contextRef="From2021-01-01to2021-03-31_custom_EGENIncMember" unitRef="USD" decimals="0">2000000</us-gaap:GoodwillAcquiredDuringPeriod>
    <us-gaap:AdjustmentForAmortization contextRef="From2021-01-01to2021-03-31_custom_EGENIncMember_custom_PurchaseAgreementMember" unitRef="USD" decimals="0">56829</us-gaap:AdjustmentForAmortization>
    <us-gaap:AdjustmentForAmortization contextRef="From2020-01-01to2020-03-31_custom_EGENIncMember_custom_PurchaseAgreementMember" unitRef="USD" decimals="0">56829</us-gaap:AdjustmentForAmortization>
    <us-gaap:OtherAccruedLiabilitiesCurrent contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">19411</us-gaap:OtherAccruedLiabilitiesCurrent>
    <us-gaap:OtherAccruedLiabilitiesCurrent contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">19411</us-gaap:OtherAccruedLiabilitiesCurrent>
    <us-gaap:AccruedProfessionalFeesCurrent contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">138430</us-gaap:AccruedProfessionalFeesCurrent>
    <us-gaap:AccruedProfessionalFeesCurrent contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">66850</us-gaap:AccruedProfessionalFeesCurrent>
    <us-gaap:EmployeeRelatedLiabilitiesCurrent contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">790111</us-gaap:EmployeeRelatedLiabilitiesCurrent>
    <us-gaap:EmployeeRelatedLiabilitiesCurrent contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">1736271</us-gaap:EmployeeRelatedLiabilitiesCurrent>
    <us-gaap:ContractualObligation contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">855517</us-gaap:ContractualObligation>
    <us-gaap:ContractualObligation contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">636000</us-gaap:ContractualObligation>
    <dei:EntityRegistrantName contextRef="From2021-01-01to2021-03-31">Celsion CORP</dei:EntityRegistrantName>
    <dei:EntityCentralIndexKey contextRef="From2021-01-01to2021-03-31">0000749647</dei:EntityCentralIndexKey>
    <dei:DocumentType contextRef="From2021-01-01to2021-03-31">10-Q</dei:DocumentType>
    <dei:DocumentPeriodEndDate contextRef="From2021-01-01to2021-03-31">2021-03-31</dei:DocumentPeriodEndDate>
    <dei:AmendmentFlag contextRef="From2021-01-01to2021-03-31">false</dei:AmendmentFlag>
    <dei:CurrentFiscalYearEndDate contextRef="From2021-01-01to2021-03-31">--12-31</dei:CurrentFiscalYearEndDate>
    <dei:EntityCurrentReportingStatus contextRef="From2021-01-01to2021-03-31">Yes</dei:EntityCurrentReportingStatus>
    <dei:EntityInteractiveDataCurrent contextRef="From2021-01-01to2021-03-31">Yes</dei:EntityInteractiveDataCurrent>
    <dei:EntityFilerCategory contextRef="From2021-01-01to2021-03-31">Non-accelerated Filer</dei:EntityFilerCategory>
    <dei:EntitySmallBusiness contextRef="From2021-01-01to2021-03-31">true</dei:EntitySmallBusiness>
    <dei:EntityEmergingGrowthCompany contextRef="From2021-01-01to2021-03-31">false</dei:EntityEmergingGrowthCompany>
    <dei:EntityShellCompany contextRef="From2021-01-01to2021-03-31">false</dei:EntityShellCompany>
    <dei:EntityCommonStockSharesOutstanding contextRef="AsOf2021-05-13" unitRef="Shares" decimals="INF">86557736</dei:EntityCommonStockSharesOutstanding>
    <dei:DocumentFiscalPeriodFocus contextRef="From2021-01-01to2021-03-31">Q1</dei:DocumentFiscalPeriodFocus>
    <us-gaap:OperatingLeaseRightOfUseAsset contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">945070</us-gaap:OperatingLeaseRightOfUseAsset>
    <us-gaap:OperatingLeaseRightOfUseAsset contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">1047336</us-gaap:OperatingLeaseRightOfUseAsset>
    <us-gaap:OperatingLeaseRightOfUseAsset contextRef="AsOf2019-01-02" unitRef="USD" decimals="0">400000</us-gaap:OperatingLeaseRightOfUseAsset>
    <us-gaap:OperatingLeaseRightOfUseAsset contextRef="AsOf2019-01-02_us-gaap_AccountingStandardsUpdate201602Member" unitRef="USD" decimals="0">1400000</us-gaap:OperatingLeaseRightOfUseAsset>
    <us-gaap:PreferredStockParOrStatedValuePerShare contextRef="AsOf2021-03-31" unitRef="USDPShares" decimals="INF">0.01</us-gaap:PreferredStockParOrStatedValuePerShare>
    <us-gaap:PreferredStockParOrStatedValuePerShare contextRef="AsOf2020-12-31" unitRef="USDPShares" decimals="INF">0.01</us-gaap:PreferredStockParOrStatedValuePerShare>
    <us-gaap:PreferredStockSharesAuthorized contextRef="AsOf2021-03-31" unitRef="Shares" decimals="INF">100000</us-gaap:PreferredStockSharesAuthorized>
    <us-gaap:PreferredStockSharesAuthorized contextRef="AsOf2020-12-31" unitRef="Shares" decimals="INF">100000</us-gaap:PreferredStockSharesAuthorized>
    <us-gaap:PreferredStockSharesIssued contextRef="AsOf2021-03-31" unitRef="Shares" xsi:nil="true" />
    <us-gaap:PreferredStockSharesIssued contextRef="AsOf2020-12-31" unitRef="Shares" xsi:nil="true" />
    <us-gaap:PreferredStockSharesOutstanding contextRef="AsOf2021-03-31" unitRef="Shares" xsi:nil="true" />
    <us-gaap:PreferredStockSharesOutstanding contextRef="AsOf2020-12-31" unitRef="Shares" xsi:nil="true" />
    <us-gaap:CommonStockParOrStatedValuePerShare contextRef="AsOf2021-03-31" unitRef="USDPShares" decimals="INF">0.01</us-gaap:CommonStockParOrStatedValuePerShare>
    <us-gaap:CommonStockParOrStatedValuePerShare contextRef="AsOf2020-12-31" unitRef="USDPShares" decimals="INF">0.01</us-gaap:CommonStockParOrStatedValuePerShare>
    <us-gaap:CommonStockSharesAuthorized contextRef="AsOf2021-03-31" unitRef="Shares" decimals="INF">112500000</us-gaap:CommonStockSharesAuthorized>
    <us-gaap:CommonStockSharesAuthorized contextRef="AsOf2020-12-31" unitRef="Shares" decimals="INF">112500000</us-gaap:CommonStockSharesAuthorized>
    <us-gaap:CommonStockSharesIssued contextRef="AsOf2021-03-31" unitRef="Shares" decimals="INF">75019608</us-gaap:CommonStockSharesIssued>
    <us-gaap:CommonStockSharesIssued contextRef="AsOf2020-12-31" unitRef="Shares" decimals="INF">40701356</us-gaap:CommonStockSharesIssued>
    <us-gaap:CommonStockSharesOutstanding contextRef="AsOf2021-03-31" unitRef="Shares" decimals="INF">75019274</us-gaap:CommonStockSharesOutstanding>
    <us-gaap:CommonStockSharesOutstanding contextRef="AsOf2020-12-31" unitRef="Shares" decimals="INF">40701022</us-gaap:CommonStockSharesOutstanding>
    <us-gaap:TreasuryStockShares contextRef="AsOf2021-03-31" unitRef="Shares" decimals="INF">334</us-gaap:TreasuryStockShares>
    <us-gaap:TreasuryStockShares contextRef="AsOf2020-12-31" unitRef="Shares" decimals="INF">334</us-gaap:TreasuryStockShares>
    <us-gaap:CommonStockValue contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">750196</us-gaap:CommonStockValue>
    <us-gaap:CommonStockValue contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">407014</us-gaap:CommonStockValue>
    <us-gaap:StockholdersEquity contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">54960058</us-gaap:StockholdersEquity>
    <us-gaap:StockholdersEquity contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">18611081</us-gaap:StockholdersEquity>
    <us-gaap:StockholdersEquity contextRef="AsOf2019-12-31_us-gaap_CommonStockMember" unitRef="USD" decimals="0">232562</us-gaap:StockholdersEquity>
    <us-gaap:StockholdersEquity contextRef="AsOf2019-12-31_us-gaap_AdditionalPaidInCapitalMember" unitRef="USD" decimals="0">304885663</us-gaap:StockholdersEquity>
    <us-gaap:StockholdersEquity contextRef="AsOf2019-12-31_us-gaap_TreasuryStockMember" unitRef="USD" decimals="0">-85188</us-gaap:StockholdersEquity>
    <us-gaap:StockholdersEquity contextRef="AsOf2019-12-31_us-gaap_AccumulatedOtherComprehensiveIncomeMember" unitRef="USD" decimals="0">42778</us-gaap:StockholdersEquity>
    <us-gaap:StockholdersEquity contextRef="AsOf2019-12-31_us-gaap_RetainedEarningsMember" unitRef="USD" decimals="0">-290516780</us-gaap:StockholdersEquity>
    <us-gaap:StockholdersEquity contextRef="AsOf2020-12-31_us-gaap_CommonStockMember" unitRef="USD" decimals="0">407014</us-gaap:StockholdersEquity>
    <us-gaap:StockholdersEquity contextRef="AsOf2020-12-31_us-gaap_AdditionalPaidInCapitalMember" unitRef="USD" decimals="0">330289596</us-gaap:StockholdersEquity>
    <us-gaap:StockholdersEquity contextRef="AsOf2020-12-31_us-gaap_TreasuryStockMember" unitRef="USD" decimals="0">-85188</us-gaap:StockholdersEquity>
    <us-gaap:StockholdersEquity contextRef="AsOf2020-12-31_us-gaap_AccumulatedOtherComprehensiveIncomeMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:StockholdersEquity contextRef="AsOf2020-12-31_us-gaap_RetainedEarningsMember" unitRef="USD" decimals="0">-312000341</us-gaap:StockholdersEquity>
    <us-gaap:StockholdersEquity contextRef="AsOf2020-03-31" unitRef="USD" decimals="0">16208536</us-gaap:StockholdersEquity>
    <us-gaap:StockholdersEquity contextRef="AsOf2020-03-31_us-gaap_CommonStockMember" unitRef="USD" decimals="0">292574</us-gaap:StockholdersEquity>
    <us-gaap:StockholdersEquity contextRef="AsOf2021-03-31_us-gaap_CommonStockMember" unitRef="USD" decimals="0">750196</us-gaap:StockholdersEquity>
    <us-gaap:StockholdersEquity contextRef="AsOf2020-03-31_us-gaap_AdditionalPaidInCapitalMember" unitRef="USD" decimals="0">311570995</us-gaap:StockholdersEquity>
    <us-gaap:StockholdersEquity contextRef="AsOf2021-03-31_us-gaap_AdditionalPaidInCapitalMember" unitRef="USD" decimals="0">371982609</us-gaap:StockholdersEquity>
    <us-gaap:StockholdersEquity contextRef="AsOf2020-03-31_us-gaap_TreasuryStockMember" unitRef="USD" decimals="0">-85188</us-gaap:StockholdersEquity>
    <us-gaap:StockholdersEquity contextRef="AsOf2021-03-31_us-gaap_TreasuryStockMember" unitRef="USD" decimals="0">-85188</us-gaap:StockholdersEquity>
    <us-gaap:StockholdersEquity contextRef="AsOf2020-03-31_us-gaap_AccumulatedOtherComprehensiveIncomeMember" unitRef="USD" decimals="0">3813</us-gaap:StockholdersEquity>
    <us-gaap:StockholdersEquity contextRef="AsOf2021-03-31_us-gaap_AccumulatedOtherComprehensiveIncomeMember" unitRef="USD" decimals="0">1785</us-gaap:StockholdersEquity>
    <us-gaap:StockholdersEquity contextRef="AsOf2020-03-31_us-gaap_RetainedEarningsMember" unitRef="USD" decimals="0">-295573658</us-gaap:StockholdersEquity>
    <us-gaap:StockholdersEquity contextRef="AsOf2021-03-31_us-gaap_RetainedEarningsMember" unitRef="USD" decimals="0">-317689344</us-gaap:StockholdersEquity>
    <us-gaap:StockholdersEquity contextRef="AsOf2019-12-31" unitRef="USD" decimals="0">14559035</us-gaap:StockholdersEquity>
    <us-gaap:NetIncomeLoss contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">-5689003</us-gaap:NetIncomeLoss>
    <us-gaap:NetIncomeLoss contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">-5056878</us-gaap:NetIncomeLoss>
    <us-gaap:NetIncomeLoss contextRef="From2020-01-01to2020-03-31_us-gaap_CommonStockMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:NetIncomeLoss contextRef="From2021-01-01to2021-03-31_us-gaap_CommonStockMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:NetIncomeLoss contextRef="From2020-01-01to2020-03-31_us-gaap_AdditionalPaidInCapitalMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:NetIncomeLoss contextRef="From2021-01-01to2021-03-31_us-gaap_AdditionalPaidInCapitalMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:NetIncomeLoss contextRef="From2020-01-01to2020-03-31_us-gaap_AccumulatedOtherComprehensiveIncomeMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:NetIncomeLoss contextRef="From2021-01-01to2021-03-31_us-gaap_AccumulatedOtherComprehensiveIncomeMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:NetIncomeLoss contextRef="From2020-01-01to2020-03-31_us-gaap_RetainedEarningsMember" unitRef="USD" decimals="0">-5056878</us-gaap:NetIncomeLoss>
    <us-gaap:NetIncomeLoss contextRef="From2021-01-01to2021-03-31_us-gaap_RetainedEarningsMember" unitRef="USD" decimals="0">-5689003</us-gaap:NetIncomeLoss>
    <us-gaap:NetIncomeLoss contextRef="From2020-01-01to2020-03-31_us-gaap_TreasuryStockMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:NetIncomeLoss contextRef="From2021-01-01to2021-03-31_us-gaap_TreasuryStockMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:AmortizationOfIntangibleAssets contextRef="From2021-01-01to2021-03-31_us-gaap_GoodwillMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:AmortizationOfIntangibleAssets contextRef="From2021-01-01to2021-03-31_custom_IPRAndDMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:AmortizationOfIntangibleAssets contextRef="From2021-01-01to2021-03-31_us-gaap_NoncompeteAgreementsMember" unitRef="USD" decimals="0">-56829</us-gaap:AmortizationOfIntangibleAssets>
    <us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights contextRef="AsOf2020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember_us-gaap_CommonStockMember" unitRef="Shares" decimals="INF">247525</us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights>
    <us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights contextRef="AsOf2018-06-27_custom_InitialHorizonCreditAgreementMember_us-gaap_CommonStockMember" unitRef="Shares" decimals="INF">190114</us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights>
    <us-gaap:Assets contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">73041035</us-gaap:Assets>
    <us-gaap:Assets contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">37527338</us-gaap:Assets>
    <us-gaap:PropertyPlantAndEquipmentNet contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">389648</us-gaap:PropertyPlantAndEquipmentNet>
    <us-gaap:PropertyPlantAndEquipmentNet contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">294551</us-gaap:PropertyPlantAndEquipmentNet>
    <us-gaap:AssetsCurrent contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">56248390</us-gaap:AssetsCurrent>
    <us-gaap:AssetsCurrent contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">18824872</us-gaap:AssetsCurrent>
    <us-gaap:CommitmentsAndContingencies contextRef="AsOf2021-03-31" unitRef="USD" xsi:nil="true" />
    <us-gaap:CommitmentsAndContingencies contextRef="AsOf2020-12-31" unitRef="USD" xsi:nil="true" />
    <us-gaap:PreferredStockValue contextRef="AsOf2021-03-31" unitRef="USD" xsi:nil="true" />
    <us-gaap:PreferredStockValue contextRef="AsOf2020-12-31" unitRef="USD" xsi:nil="true" />
    <us-gaap:WeightedAverageNumberOfShareOutstandingBasicAndDiluted contextRef="From2021-01-01to2021-03-31" unitRef="Shares" decimals="INF">66298723</us-gaap:WeightedAverageNumberOfShareOutstandingBasicAndDiluted>
    <us-gaap:WeightedAverageNumberOfShareOutstandingBasicAndDiluted contextRef="From2020-01-01to2020-03-31" unitRef="Shares" decimals="INF">25804349</us-gaap:WeightedAverageNumberOfShareOutstandingBasicAndDiluted>
    <us-gaap:EarningsPerShareBasicAndDiluted contextRef="From2021-01-01to2021-03-31" unitRef="USDPShares" decimals="INF">-0.09</us-gaap:EarningsPerShareBasicAndDiluted>
    <us-gaap:EarningsPerShareBasicAndDiluted contextRef="From2020-01-01to2020-03-31" unitRef="USDPShares" decimals="INF">-0.20</us-gaap:EarningsPerShareBasicAndDiluted>
    <us-gaap:NonoperatingIncomeExpense contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">-305659</us-gaap:NonoperatingIncomeExpense>
    <us-gaap:NonoperatingIncomeExpense contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">-290923</us-gaap:NonoperatingIncomeExpense>
    <us-gaap:OtherNonoperatingIncomeExpense contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">544</us-gaap:OtherNonoperatingIncomeExpense>
    <us-gaap:OtherNonoperatingIncomeExpense contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">1407</us-gaap:OtherNonoperatingIncomeExpense>
    <us-gaap:InterestAndDebtExpense contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">157614</us-gaap:InterestAndDebtExpense>
    <us-gaap:InterestAndDebtExpense contextRef="From2018-06-26to2018-06-27_custom_InitialHorizonCreditAgreementMember" unitRef="USD" decimals="0">175000</us-gaap:InterestAndDebtExpense>
    <us-gaap:InterestAndDebtExpense contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">339365</us-gaap:InterestAndDebtExpense>
    <us-gaap:InvestmentIncomeNonoperating contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">2411</us-gaap:InvestmentIncomeNonoperating>
    <us-gaap:InvestmentIncomeNonoperating contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">88309</us-gaap:InvestmentIncomeNonoperating>
    <us-gaap:OperatingIncomeLoss contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">-5383344</us-gaap:OperatingIncomeLoss>
    <us-gaap:OperatingIncomeLoss contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">-4765955</us-gaap:OperatingIncomeLoss>
    <us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">125000</us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax>
    <us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">125000</us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax>
    <us-gaap:ComprehensiveIncomeNetOfTax contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">-5687218</us-gaap:ComprehensiveIncomeNetOfTax>
    <us-gaap:ComprehensiveIncomeNetOfTax contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">-5095843</us-gaap:ComprehensiveIncomeNetOfTax>
    <us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax contextRef="From2021-01-01to2021-03-31" unitRef="USD" xsi:nil="true" />
    <us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">43232</us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax>
    <us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">37759327</us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations>
    <us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">17164177</us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations>
    <us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations contextRef="AsOf2020-03-31" unitRef="USD" decimals="0">5746184</us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations>
    <us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations contextRef="AsOf2019-12-31" unitRef="USD" decimals="0">6875273</us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations>
    <us-gaap:DebtInstrumentInterestRateStatedPercentage contextRef="AsOf2020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember_custom_OneMonthLondonInterbankOfferedRateLIBORExceedsTwoPeercentagePlusMember" unitRef="Percentage" decimals="INF">0.09625</us-gaap:DebtInstrumentInterestRateStatedPercentage>
    <us-gaap:DebtInstrumentInterestRateStatedPercentage contextRef="AsOf2018-06-30_custom_HorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember_us-gaap_LondonInterbankOfferedRateLIBORMember" unitRef="Percentage" decimals="INF">0.07625</us-gaap:DebtInstrumentInterestRateStatedPercentage>
    <us-gaap:RepaymentsOfNotesPayable contextRef="From2020-08-27to2020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember" unitRef="USD" decimals="0">5000000</us-gaap:RepaymentsOfNotesPayable>
    <us-gaap:DebtInstrumentFaceAmount contextRef="AsOf2020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember" unitRef="USD" decimals="0">5000000</us-gaap:DebtInstrumentFaceAmount>
    <us-gaap:DebtInstrumentFaceAmount contextRef="AsOf2020-08-28_custom_HorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember" unitRef="USD" decimals="0">10000000</us-gaap:DebtInstrumentFaceAmount>
    <us-gaap:DebtInstrumentFaceAmount contextRef="AsOf2021-01-31_custom_CapitalOnDemandTMSalesAgreementMember_custom_JonesTradingInstitutionalServicesLLCMember" unitRef="USD" decimals="0">35000000</us-gaap:DebtInstrumentFaceAmount>
    <CLSN:PaymentOfDebtEndTermCharges contextRef="From2020-08-27to2020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember" unitRef="USD" decimals="0">200000</CLSN:PaymentOfDebtEndTermCharges>
    <us-gaap:LineOfCreditFacilityMaximumBorrowingCapacity contextRef="AsOf2018-06-27_custom_InitialHorizonCreditAgreementMember" unitRef="USD" decimals="0">10000000</us-gaap:LineOfCreditFacilityMaximumBorrowingCapacity>
    <us-gaap:ProceedsFromLinesOfCredit contextRef="From2018-06-26to2018-06-27_custom_InitialHorizonCreditAgreementMember" unitRef="USD" decimals="0">10000000</us-gaap:ProceedsFromLinesOfCredit>
    <us-gaap:DebtInstrumentInterestRateTerms contextRef="From2020-08-27to2020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember">The obligations bear 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 are 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 maturity date on April 1, 2023. </us-gaap:DebtInstrumentInterestRateTerms>
    <us-gaap:DebtInstrumentFeeAmount contextRef="AsOf2020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember" unitRef="USD" decimals="0">275000</us-gaap:DebtInstrumentFeeAmount>
    <us-gaap:DebtInstrumentFeeAmount contextRef="AsOf2018-06-27_custom_InitialHorizonCreditAgreementMember" unitRef="USD" decimals="0">142605</us-gaap:DebtInstrumentFeeAmount>
    <us-gaap:DebtInstrumentRestrictiveCovenants contextRef="From2020-08-27to2020-08-28_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:LoanProcessingFee contextRef="From2018-06-26to2018-06-27_custom_InitialHorizonCreditAgreementMember" unitRef="USD" decimals="0">100000</us-gaap:LoanProcessingFee>
    <us-gaap:DebtInstrumentUnamortizedDiscount contextRef="AsOf2020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember" unitRef="USD" decimals="0">200000</us-gaap:DebtInstrumentUnamortizedDiscount>
    <us-gaap:DebtInstrumentUnamortizedDiscount contextRef="AsOf2021-03-31_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember" unitRef="USD" decimals="0">109706</us-gaap:DebtInstrumentUnamortizedDiscount>
    <us-gaap:DebtInstrumentUnamortizedDiscount contextRef="AsOf2018-06-27_custom_InitialHorizonCreditAgreementMember" unitRef="USD" decimals="0">782116</us-gaap:DebtInstrumentUnamortizedDiscount>
    <us-gaap:FairValueAdjustmentOfWarrants contextRef="From2018-06-26to2018-06-27_custom_InitialHorizonCreditAgreementMember" unitRef="USD" decimals="0">507116</us-gaap:FairValueAdjustmentOfWarrants>
    <CLSN:ClassOfWarrantOrRightWarrantsOrRightsCancelled contextRef="AsOf2020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember_us-gaap_CommonStockMember" unitRef="Shares" decimals="INF">95057</CLSN:ClassOfWarrantOrRightWarrantsOrRightsCancelled>
    <us-gaap:ClassOfWarrantOrRightOutstanding contextRef="AsOf2018-06-27_custom_InitialHorizonCreditAgreementMember_us-gaap_CommonStockMember" unitRef="Shares" decimals="INF">95057</us-gaap:ClassOfWarrantOrRightOutstanding>
    <us-gaap:PaymentsOfDebtExtinguishmentCosts contextRef="From2020-08-27to2020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember" unitRef="USD" decimals="0">5000000</us-gaap:PaymentsOfDebtExtinguishmentCosts>
    <us-gaap:DeferredFinanceCostsNet contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">88461</us-gaap:DeferredFinanceCostsNet>
    <us-gaap:DeferredFinanceCostsNet contextRef="AsOf2020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember" unitRef="USD" decimals="0">5000</us-gaap:DeferredFinanceCostsNet>
    <us-gaap:DeferredFinanceCostsNet contextRef="AsOf2018-06-27_custom_InitialHorizonCreditAgreementMember" unitRef="USD" decimals="0">400000</us-gaap:DeferredFinanceCostsNet>
    <us-gaap:WarrantsNotSettleableInCashFairValueDisclosure contextRef="AsOf2020-08-28_custom_AmendmentToHorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember" unitRef="USD" decimals="0">247548</us-gaap:WarrantsNotSettleableInCashFairValueDisclosure>
    <us-gaap:InterestExpenseDebt contextRef="From2020-01-01to2020-03-31_custom_InitialHorizonCreditAgreementAmendmentMember" unitRef="USD" decimals="0">243299</us-gaap:InterestExpenseDebt>
    <us-gaap:InterestExpenseDebt contextRef="From2021-01-01to2021-03-31_custom_InitialHorizonCreditAgreementAmendmentMember" unitRef="USD" decimals="0">120313</us-gaap:InterestExpenseDebt>
    <us-gaap:AmortizationOfFinancingCosts contextRef="From2020-01-01to2020-03-31_custom_InitialHorizonCreditAgreementAmendmentMember" unitRef="USD" decimals="0">96066</us-gaap:AmortizationOfFinancingCosts>
    <us-gaap:AmortizationOfFinancingCosts contextRef="From2021-01-01to2021-03-31_custom_InitialHorizonCreditAgreementAmendmentMember" unitRef="USD" decimals="0">37301</us-gaap:AmortizationOfFinancingCosts>
    <us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">1904760</us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths>
    <us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">2857140</us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo>
    <us-gaap:LongTermDebt contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">5088461</us-gaap:LongTermDebt>
    <CLSN:EndOfTermChargePercentage contextRef="From2018-06-26to2018-06-27_custom_InitialHorizonCreditAgreementMember" unitRef="Percentage" decimals="INF">0.040</CLSN:EndOfTermChargePercentage>
    <CLSN:EndOfTermFees contextRef="From2018-06-26to2018-06-27_custom_InitialHorizonCreditAgreementMember" unitRef="USD" decimals="0">275000</CLSN:EndOfTermFees>
    <us-gaap:OtherAssetsNoncurrent contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">16402997</us-gaap:OtherAssetsNoncurrent>
    <us-gaap:OtherAssetsNoncurrent contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">18407915</us-gaap:OtherAssetsNoncurrent>
    <dei:DocumentFiscalYearFocus contextRef="From2021-01-01to2021-03-31">2021</dei:DocumentFiscalYearFocus>
    <us-gaap:SharesOutstanding contextRef="AsOf2019-12-31_us-gaap_CommonStockMember" unitRef="Shares" decimals="INF">23255818</us-gaap:SharesOutstanding>
    <us-gaap:SharesOutstanding contextRef="AsOf2019-12-31_us-gaap_TreasuryStockMember" unitRef="Shares" decimals="INF">334</us-gaap:SharesOutstanding>
    <us-gaap:SharesOutstanding contextRef="AsOf2020-12-31_us-gaap_CommonStockMember" unitRef="Shares" decimals="INF">40701022</us-gaap:SharesOutstanding>
    <us-gaap:SharesOutstanding contextRef="AsOf2020-12-31_us-gaap_TreasuryStockMember" unitRef="Shares" decimals="INF">334</us-gaap:SharesOutstanding>
    <us-gaap:SharesOutstanding contextRef="AsOf2020-03-31_us-gaap_CommonStockMember" unitRef="Shares" decimals="INF">29257101</us-gaap:SharesOutstanding>
    <us-gaap:SharesOutstanding contextRef="AsOf2021-03-31_us-gaap_CommonStockMember" unitRef="Shares" decimals="INF">75019274</us-gaap:SharesOutstanding>
    <us-gaap:SharesOutstanding contextRef="AsOf2020-03-31_us-gaap_TreasuryStockMember" unitRef="Shares" decimals="INF">334</us-gaap:SharesOutstanding>
    <us-gaap:SharesOutstanding contextRef="AsOf2021-03-31_us-gaap_TreasuryStockMember" unitRef="Shares" decimals="INF">334</us-gaap:SharesOutstanding>
    <us-gaap:StockIssuedDuringPeriodValueRestrictedStockAwardGross contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">498632</us-gaap:StockIssuedDuringPeriodValueRestrictedStockAwardGross>
    <us-gaap:StockIssuedDuringPeriodValueRestrictedStockAwardGross contextRef="From2020-01-01to2020-03-31_us-gaap_CommonStockMember" unitRef="USD" decimals="0">4299</us-gaap:StockIssuedDuringPeriodValueRestrictedStockAwardGross>
    <us-gaap:StockIssuedDuringPeriodValueRestrictedStockAwardGross contextRef="From2020-01-01to2020-03-31_us-gaap_AdditionalPaidInCapitalMember" unitRef="USD" decimals="0">494333</us-gaap:StockIssuedDuringPeriodValueRestrictedStockAwardGross>
    <us-gaap:StockIssuedDuringPeriodValueRestrictedStockAwardGross contextRef="From2020-01-01to2020-03-31_us-gaap_AccumulatedOtherComprehensiveIncomeMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:StockIssuedDuringPeriodValueRestrictedStockAwardGross contextRef="From2020-01-01to2020-03-31_us-gaap_RetainedEarningsMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:StockIssuedDuringPeriodValueRestrictedStockAwardGross contextRef="From2020-01-01to2020-03-31_us-gaap_TreasuryStockMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:StockIssuedDuringPeriodSharesRestrictedStockAwardGross contextRef="From2020-01-01to2020-03-31_us-gaap_CommonStockMember" unitRef="Shares" decimals="INF">429855</us-gaap:StockIssuedDuringPeriodSharesRestrictedStockAwardGross>
    <us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">1785</us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent>
    <us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">-38965</us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent>
    <us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent contextRef="From2020-01-01to2020-03-31_us-gaap_CommonStockMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent contextRef="From2021-01-01to2021-03-31_us-gaap_CommonStockMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent contextRef="From2020-01-01to2020-03-31_us-gaap_AdditionalPaidInCapitalMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent contextRef="From2021-01-01to2021-03-31_us-gaap_AdditionalPaidInCapitalMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent contextRef="From2020-01-01to2020-03-31_us-gaap_AccumulatedOtherComprehensiveIncomeMember" unitRef="USD" decimals="0">-38965</us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent>
    <us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent contextRef="From2021-01-01to2021-03-31_us-gaap_AccumulatedOtherComprehensiveIncomeMember" unitRef="USD" decimals="0">1785</us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent>
    <us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent contextRef="From2020-01-01to2020-03-31_us-gaap_RetainedEarningsMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent contextRef="From2021-01-01to2021-03-31_us-gaap_RetainedEarningsMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent contextRef="From2020-01-01to2020-03-31_us-gaap_TreasuryStockMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent contextRef="From2021-01-01to2021-03-31_us-gaap_TreasuryStockMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">1579326</us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue>
    <us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">451965</us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue>
    <us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue contextRef="From2020-01-01to2020-03-31_us-gaap_CommonStockMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue contextRef="From2021-01-01to2021-03-31_us-gaap_CommonStockMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue contextRef="From2020-01-01to2020-03-31_us-gaap_AdditionalPaidInCapitalMember" unitRef="USD" decimals="0">451965</us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue>
    <us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue contextRef="From2021-01-01to2021-03-31_us-gaap_AdditionalPaidInCapitalMember" unitRef="USD" decimals="0">1579326</us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue>
    <us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue contextRef="From2020-01-01to2020-03-31_us-gaap_AccumulatedOtherComprehensiveIncomeMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue contextRef="From2021-01-01to2021-03-31_us-gaap_AccumulatedOtherComprehensiveIncomeMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue contextRef="From2020-01-01to2020-03-31_us-gaap_RetainedEarningsMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue contextRef="From2021-01-01to2021-03-31_us-gaap_RetainedEarningsMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue contextRef="From2020-01-01to2020-03-31_us-gaap_TreasuryStockMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue contextRef="From2021-01-01to2021-03-31_us-gaap_TreasuryStockMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:GrantsReceivableCurrent contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">1643195</us-gaap:GrantsReceivableCurrent>
    <us-gaap:GrantsReceivableCurrent contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">1660695</us-gaap:GrantsReceivableCurrent>
    <CLSN:ReceivableOnSaleOfNetOperatingLosses contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">1845823</CLSN:ReceivableOnSaleOfNetOperatingLosses>
    <CLSN:ReceivableOnSaleOfNetOperatingLosses contextRef="AsOf2020-12-31" unitRef="USD" xsi:nil="true" />
    <us-gaap:CashAndCashEquivalentsAtCarryingValue contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">37759327</us-gaap:CashAndCashEquivalentsAtCarryingValue>
    <us-gaap:CashAndCashEquivalentsAtCarryingValue contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">17164177</us-gaap:CashAndCashEquivalentsAtCarryingValue>
    <us-gaap:DepositsAssetsNoncurrent contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">58761</us-gaap:DepositsAssetsNoncurrent>
    <us-gaap:DepositsAssetsNoncurrent contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">58761</us-gaap:DepositsAssetsNoncurrent>
    <us-gaap:Goodwill contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">1976101</us-gaap:Goodwill>
    <us-gaap:Goodwill contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">1976101</us-gaap:Goodwill>
    <us-gaap:IndefiniteLivedIntangibleAssetsExcludingGoodwill contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">13366234</us-gaap:IndefiniteLivedIntangibleAssetsExcludingGoodwill>
    <us-gaap:IndefiniteLivedIntangibleAssetsExcludingGoodwill contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">13366234</us-gaap:IndefiniteLivedIntangibleAssetsExcludingGoodwill>
    <us-gaap:DeferredIncomeTaxAssetsNet contextRef="AsOf2021-03-31" unitRef="USD" xsi:nil="true" />
    <us-gaap:DeferredIncomeTaxAssetsNet contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">1845823</us-gaap:DeferredIncomeTaxAssetsNet>
    <us-gaap:LiabilitiesCurrent contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">6690329</us-gaap:LiabilitiesCurrent>
    <us-gaap:LiabilitiesCurrent contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">6753455</us-gaap:LiabilitiesCurrent>
    <us-gaap:ContractWithCustomerLiabilityCurrent contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">500000</us-gaap:ContractWithCustomerLiabilityCurrent>
    <us-gaap:ContractWithCustomerLiabilityCurrent contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">500000</us-gaap:ContractWithCustomerLiabilityCurrent>
    <us-gaap:OperatingLeaseLiabilityCurrent contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">445560</us-gaap:OperatingLeaseLiabilityCurrent>
    <us-gaap:OperatingLeaseLiabilityCurrent contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">433413</us-gaap:OperatingLeaseLiabilityCurrent>
    <us-gaap:NotesPayableCurrent contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">1836436</us-gaap:NotesPayableCurrent>
    <us-gaap:NotesPayableCurrent contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">1116663</us-gaap:NotesPayableCurrent>
    <us-gaap:AccruedLiabilitiesCurrent contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">1803469</us-gaap:AccruedLiabilitiesCurrent>
    <us-gaap:AccruedLiabilitiesCurrent contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">2458532</us-gaap:AccruedLiabilitiesCurrent>
    <us-gaap:AccountsPayableCurrent contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">2104864</us-gaap:AccountsPayableCurrent>
    <us-gaap:AccountsPayableCurrent contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">2244847</us-gaap:AccountsPayableCurrent>
    <us-gaap:Liabilities contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">18080977</us-gaap:Liabilities>
    <us-gaap:Liabilities contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">18916257</us-gaap:Liabilities>
    <us-gaap:DeferredRevenueNoncurrent contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">375000</us-gaap:DeferredRevenueNoncurrent>
    <us-gaap:DeferredRevenueNoncurrent contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">500000</us-gaap:DeferredRevenueNoncurrent>
    <us-gaap:OperatingLeaseLiabilityNoncurrent contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">594623</us-gaap:OperatingLeaseLiabilityNoncurrent>
    <us-gaap:OperatingLeaseLiabilityNoncurrent contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">710305</us-gaap:OperatingLeaseLiabilityNoncurrent>
    <us-gaap:LongTermNotesPayable contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">3252025</us-gaap:LongTermNotesPayable>
    <us-gaap:LongTermNotesPayable contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">3934497</us-gaap:LongTermNotesPayable>
    <us-gaap:StockholdersEquityBeforeTreasuryStock contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">55045246</us-gaap:StockholdersEquityBeforeTreasuryStock>
    <us-gaap:StockholdersEquityBeforeTreasuryStock contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">18696269</us-gaap:StockholdersEquityBeforeTreasuryStock>
    <us-gaap:RetainedEarningsAccumulatedDeficit contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">-317689344</us-gaap:RetainedEarningsAccumulatedDeficit>
    <us-gaap:RetainedEarningsAccumulatedDeficit contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">-312000341</us-gaap:RetainedEarningsAccumulatedDeficit>
    <us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">1785</us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax>
    <us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax contextRef="AsOf2020-12-31" unitRef="USD" xsi:nil="true" />
    <us-gaap:AdditionalPaidInCapital contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">371982609</us-gaap:AdditionalPaidInCapital>
    <us-gaap:AdditionalPaidInCapital contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">330289596</us-gaap:AdditionalPaidInCapital>
    <us-gaap:TreasuryStockValue contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">85188</us-gaap:TreasuryStockValue>
    <us-gaap:TreasuryStockValue contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">85188</us-gaap:TreasuryStockValue>
    <us-gaap:LiabilitiesAndStockholdersEquity contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">73041035</us-gaap:LiabilitiesAndStockholdersEquity>
    <us-gaap:LiabilitiesAndStockholdersEquity contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">37527338</us-gaap:LiabilitiesAndStockholdersEquity>
    <us-gaap:OperatingExpenses contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">5508344</us-gaap:OperatingExpenses>
    <us-gaap:OperatingExpenses contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">4890995</us-gaap:OperatingExpenses>
    <us-gaap:GeneralAndAdministrativeExpense contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">2936771</us-gaap:GeneralAndAdministrativeExpense>
    <us-gaap:GeneralAndAdministrativeExpense contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">1838906</us-gaap:GeneralAndAdministrativeExpense>
    <us-gaap:ResearchAndDevelopmentExpense contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">2571573</us-gaap:ResearchAndDevelopmentExpense>
    <us-gaap:ResearchAndDevelopmentExpense contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">3052049</us-gaap:ResearchAndDevelopmentExpense>
    <us-gaap:OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">1785</us-gaap:OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax>
    <us-gaap:OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">4267</us-gaap:OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax>
    <us-gaap:OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">1785</us-gaap:OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax>
    <us-gaap:OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">-38965</us-gaap:OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax>
    <us-gaap:NetCashProvidedByUsedInOperatingActivities contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">-4736862</us-gaap:NetCashProvidedByUsedInOperatingActivities>
    <us-gaap:NetCashProvidedByUsedInOperatingActivities contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">-4975067</us-gaap:NetCashProvidedByUsedInOperatingActivities>
    <us-gaap:IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">-17500</us-gaap:IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets>
    <us-gaap:IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">64527</us-gaap:IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets>
    <us-gaap:IncreaseDecreaseInAccruedInvestmentIncomeReceivable contextRef="From2021-01-01to2021-03-31" unitRef="USD" xsi:nil="true" />
    <us-gaap:IncreaseDecreaseInAccruedInvestmentIncomeReceivable contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">1344</us-gaap:IncreaseDecreaseInAccruedInvestmentIncomeReceivable>
    <CLSN:AmortizationOfDeferredFinanceChargesAndDebtDiscountAssociatedWithNotePayable contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">37301</CLSN:AmortizationOfDeferredFinanceChargesAndDebtDiscountAssociatedWithNotePayable>
    <CLSN:AmortizationOfDeferredFinanceChargesAndDebtDiscountAssociatedWithNotePayable contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">96066</CLSN:AmortizationOfDeferredFinanceChargesAndDebtDiscountAssociatedWithNotePayable>
    <us-gaap:ShareBasedCompensation contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">1579326</us-gaap:ShareBasedCompensation>
    <us-gaap:ShareBasedCompensation contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">451965</us-gaap:ShareBasedCompensation>
    <CLSN:FairValueOfWarrantsIssuedInConnectionWithAmendmentToModifyEarnoutMilestonePayments contextRef="From2021-01-01to2021-03-31" unitRef="USD" xsi:nil="true" />
    <CLSN:FairValueOfWarrantsIssuedInConnectionWithAmendmentToModifyEarnoutMilestonePayments contextRef="From2020-01-01to2020-03-31" unitRef="USD" xsi:nil="true" />
    <us-gaap:DepreciationDepletionAndAmortization contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">190595</us-gaap:DepreciationDepletionAndAmortization>
    <us-gaap:DepreciationDepletionAndAmortization contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">188329</us-gaap:DepreciationDepletionAndAmortization>
    <us-gaap:NetCashProvidedByUsedInInvestingActivities contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">-15124857</us-gaap:NetCashProvidedByUsedInInvestingActivities>
    <us-gaap:NetCashProvidedByUsedInInvestingActivities contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">-1948769</us-gaap:NetCashProvidedByUsedInInvestingActivities>
    <us-gaap:PaymentsToAcquirePropertyPlantAndEquipment contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">126597</us-gaap:PaymentsToAcquirePropertyPlantAndEquipment>
    <us-gaap:PaymentsToAcquirePropertyPlantAndEquipment contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">8235</us-gaap:PaymentsToAcquirePropertyPlantAndEquipment>
    <us-gaap:ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities contextRef="From2021-01-01to2021-03-31" unitRef="USD" xsi:nil="true" />
    <us-gaap:ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">8000000</us-gaap:ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities>
    <us-gaap:NetCashProvidedByUsedInFinancingActivities contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">40456869</us-gaap:NetCashProvidedByUsedInFinancingActivities>
    <us-gaap:NetCashProvidedByUsedInFinancingActivities contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">5794747</us-gaap:NetCashProvidedByUsedInFinancingActivities>
    <us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">20595150</us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect>
    <us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">-1129089</us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect>
    <us-gaap:OperatingLeasePayments contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">130595</us-gaap:OperatingLeasePayments>
    <us-gaap:OperatingLeasePayments contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">130631</us-gaap:OperatingLeasePayments>
    <us-gaap:OperatingLeasePayments contextRef="From2021-01-01to2021-03-31_custom_OperatingLeasesMember" unitRef="USD" decimals="0">131863</us-gaap:OperatingLeasePayments>
    <us-gaap:OperatingLeasePayments contextRef="From2020-01-01to2020-03-31_custom_OperatingLeasesMember" unitRef="USD" decimals="0">130631</us-gaap:OperatingLeasePayments>
    <CLSN:RealizedAndUnrealizedGainsAndLossesNetOnInvestmentInDebtSecurities contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">1785</CLSN:RealizedAndUnrealizedGainsAndLossesNetOnInvestmentInDebtSecurities>
    <CLSN:RealizedAndUnrealizedGainsAndLossesNetOnInvestmentInDebtSecurities contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">-38965</CLSN:RealizedAndUnrealizedGainsAndLossesNetOnInvestmentInDebtSecurities>
    <us-gaap:DeferredIncomeTaxExpenseBenefit contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">1845823</us-gaap:DeferredIncomeTaxExpenseBenefit>
    <us-gaap:DeferredIncomeTaxExpenseBenefit contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">1819324</us-gaap:DeferredIncomeTaxExpenseBenefit>
    <CLSN:StockIssuedUponExerciseOfCommonStockWarrants contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">1508666</CLSN:StockIssuedUponExerciseOfCommonStockWarrants>
    <CLSN:StockIssuedUponExerciseOfCommonStockWarrants contextRef="From2021-01-01to2021-03-31_us-gaap_CommonStockMember" unitRef="USD" decimals="0">12166</CLSN:StockIssuedUponExerciseOfCommonStockWarrants>
    <CLSN:StockIssuedUponExerciseOfCommonStockWarrants contextRef="From2021-01-01to2021-03-31_us-gaap_AdditionalPaidInCapitalMember" unitRef="USD" decimals="0">1496500</CLSN:StockIssuedUponExerciseOfCommonStockWarrants>
    <CLSN:StockIssuedUponExerciseOfCommonStockWarrants contextRef="From2021-01-01to2021-03-31_us-gaap_AccumulatedOtherComprehensiveIncomeMember" unitRef="USD" xsi:nil="true" />
    <CLSN:StockIssuedUponExerciseOfCommonStockWarrants contextRef="From2021-01-01to2021-03-31_us-gaap_RetainedEarningsMember" unitRef="USD" xsi:nil="true" />
    <CLSN:StockIssuedUponExerciseOfCommonStockWarrants contextRef="From2021-01-01to2021-03-31_us-gaap_TreasuryStockMember" unitRef="USD" xsi:nil="true" />
    <CLSN:StockIssuedUponExerciseOfCommonStockWarrantsShares contextRef="From2021-01-01to2021-03-31_us-gaap_CommonStockMember" unitRef="Shares" decimals="INF">1216667</CLSN:StockIssuedUponExerciseOfCommonStockWarrantsShares>
    <CLSN:LongTermDebtMaturitiesRepaymentsOfPrincipalYearFourAndThereAfter contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">238100</CLSN:LongTermDebtMaturitiesRepaymentsOfPrincipalYearFourAndThereAfter>
    <us-gaap:DebtInstrumentCarryingAmount contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">5000000</us-gaap:DebtInstrumentCarryingAmount>
    <CLSN:NetProceedsFromSaleOfNetOperatingLosses contextRef="From2018-01-01to2018-12-31_custom_NJMember" unitRef="USD" decimals="0">13000000</CLSN:NetProceedsFromSaleOfNetOperatingLosses>
    <CLSN:NetProceedsFromSaleOfNetOperatingLosses contextRef="From2019-01-01to2019-12-31_custom_NJMember" unitRef="USD" decimals="0">12200000</CLSN:NetProceedsFromSaleOfNetOperatingLosses>
    <CLSN:NetProceedsFromSaleOfNetOperatingLosses contextRef="From2020-09-01to2020-09-30_custom_NJMember" unitRef="USD" decimals="0">2000000</CLSN:NetProceedsFromSaleOfNetOperatingLosses>
    <CLSN:NetProceedsFromSaleOfNetOperatingLosses contextRef="From2021-05-09to2021-05-10_custom_NJMember_srt_MinimumMember_us-gaap_SubsequentEventMember" unitRef="USD" decimals="0">15000000</CLSN:NetProceedsFromSaleOfNetOperatingLosses>
    <CLSN:NetProceedsFromSaleOfNetOperatingLosses contextRef="From2021-05-09to2021-05-10_us-gaap_SubsequentEventMember_custom_NJMember_srt_MaximumMember" unitRef="USD" decimals="0">20000000</CLSN:NetProceedsFromSaleOfNetOperatingLosses>
    <us-gaap:ProceedsFromContributedCapital contextRef="From2018-06-01to2018-06-30_custom_HorizonCreditAgreementMember_custom_HorizonTechnologyFinanceCorporationMember" unitRef="USD" decimals="0">10000000</us-gaap:ProceedsFromContributedCapital>
    <us-gaap:ProceedsFromContributedCapital contextRef="From2021-03-17to2021-03-19_custom_CapitalOnDemandTMSalesAgreementMember_custom_JonesTradingInstitutionalServicesLLCMember" unitRef="USD" decimals="0">6900000</us-gaap:ProceedsFromContributedCapital>
    <us-gaap:ProceedsFromWarrantExercises contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">1508666</us-gaap:ProceedsFromWarrantExercises>
    <us-gaap:ProceedsFromWarrantExercises contextRef="From2020-01-01to2020-03-31" unitRef="USD" xsi:nil="true" />
    <us-gaap:ProceedsFromWarrantExercises contextRef="From2021-01-01to2021-01-31_custom_CapitalOnDemandTMSalesAgreementMember_custom_JonesTradingInstitutionalServicesLLCMember" unitRef="USD" decimals="0">1500000</us-gaap:ProceedsFromWarrantExercises>
    <us-gaap:ProceedsFromIssuanceOrSaleOfEquity contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">15000000</us-gaap:ProceedsFromIssuanceOrSaleOfEquity>
    <CLSN:NumberOfSharesOfCommonStockIssuableUponExerciseOfWarrantsAndEquityAwards contextRef="From2021-01-01to2021-03-31" unitRef="Shares" decimals="INF">9197728</CLSN:NumberOfSharesOfCommonStockIssuableUponExerciseOfWarrantsAndEquityAwards>
    <CLSN:NumberOfSharesOfCommonStockIssuableUponExerciseOfWarrantsAndEquityAwards contextRef="From2020-01-01to2020-03-31" unitRef="Shares" decimals="INF">7982990</CLSN:NumberOfSharesOfCommonStockIssuableUponExerciseOfWarrantsAndEquityAwards>
    <CLSN:NumberOfSharesOfCommonStockIssuedInCalculationBasicLossPerShare contextRef="From2020-01-01to2020-03-31" unitRef="Shares" decimals="INF">200000</CLSN:NumberOfSharesOfCommonStockIssuedInCalculationBasicLossPerShare>
    <us-gaap:ShortTermInvestments contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">14998260</us-gaap:ShortTermInvestments>
    <us-gaap:ShortTermInvestments contextRef="AsOf2020-12-31" unitRef="USD" xsi:nil="true" />
    <us-gaap:ShortTermInvestments contextRef="AsOf2021-03-31_us-gaap_CorporateDebtSecuritiesMember" unitRef="USD" decimals="0">14998260</us-gaap:ShortTermInvestments>
    <us-gaap:ShortTermInvestments contextRef="AsOf2020-12-31_us-gaap_CorporateDebtSecuritiesMember" unitRef="USD" xsi:nil="true" />
    <CLSN:DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingWithinThreeMonthsAmortizedCost contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">8998879</CLSN:DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingWithinThreeMonthsAmortizedCost>
    <CLSN:DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingWithinThreeMonthsAmortizedCost contextRef="AsOf2020-12-31" unitRef="USD" xsi:nil="true" />
    <CLSN:DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingBetweenThreeAndTwelveMonthsAmortizedCost contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">5999381</CLSN:DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingBetweenThreeAndTwelveMonthsAmortizedCost>
    <CLSN:DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingBetweenThreeAndTwelveMonthsAmortizedCost contextRef="AsOf2020-12-31" unitRef="USD" xsi:nil="true" />
    <CLSN:AvailableForSaleDebtSecuritiesAmortizedCostBasisCurrent contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">14998260</CLSN:AvailableForSaleDebtSecuritiesAmortizedCostBasisCurrent>
    <CLSN:AvailableForSaleDebtSecuritiesAmortizedCostBasisCurrent contextRef="AsOf2020-12-31" unitRef="USD" xsi:nil="true" />
    <CLSN:DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingWithinThreeMonthsFairValue contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">8999790</CLSN:DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingWithinThreeMonthsFairValue>
    <CLSN:DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingWithinThreeMonthsFairValue contextRef="AsOf2020-12-31" unitRef="USD" xsi:nil="true" />
    <CLSN:DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingBetweenThreeAndTwelveMonthsFairValue contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">6000255</CLSN:DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingBetweenThreeAndTwelveMonthsFairValue>
    <CLSN:DebtSecuritiesAvailableforsaleMaturityAllocatedAndSingleMaturityDateRollingBetweenThreeAndTwelveMonthsFairValue contextRef="AsOf2020-12-31" unitRef="USD" xsi:nil="true" />
    <us-gaap:AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">15000045</us-gaap:AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate>
    <us-gaap:AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate contextRef="AsOf2020-12-31" unitRef="USD" xsi:nil="true" />
    <CLSN:DebtSecuritiesAvailableforsaleContinuousUnrealizedGainPositionLessThan12Months contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">15000045</CLSN:DebtSecuritiesAvailableforsaleContinuousUnrealizedGainPositionLessThan12Months>
    <CLSN:DebtSecuritiesAvailableforsaleContinuousUnrealizedGainPositionLessThan12Months contextRef="AsOf2020-12-31" unitRef="USD" xsi:nil="true" />
    <CLSN:DebtSecuritiesAvailableforsaleContinuousUnrealizedGainPositionLessThan12MonthsAccumulatedGain contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">1785</CLSN:DebtSecuritiesAvailableforsaleContinuousUnrealizedGainPositionLessThan12MonthsAccumulatedGain>
    <CLSN:DebtSecuritiesAvailableforsaleContinuousUnrealizedGainPositionLessThan12MonthsAccumulatedGain contextRef="AsOf2020-12-31" unitRef="USD" xsi:nil="true" />
    <CLSN:AvailableforsaleSecuritiesDebtSecuritiesCurrentAccumulatedUnrealizedGainLoss contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">1785</CLSN:AvailableforsaleSecuritiesDebtSecuritiesCurrentAccumulatedUnrealizedGainLoss>
    <CLSN:AvailableforsaleSecuritiesDebtSecuritiesCurrentAccumulatedUnrealizedGainLoss contextRef="AsOf2020-12-31" unitRef="USD" xsi:nil="true" />
    <us-gaap:InvestmentIncomeInterestAndDividend contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">2411</us-gaap:InvestmentIncomeInterestAndDividend>
    <us-gaap:InvestmentIncomeInterestAndDividend contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">45077</us-gaap:InvestmentIncomeInterestAndDividend>
    <us-gaap:AvailableForSaleSecuritiesGrossRealizedGainLossNet contextRef="From2021-01-01to2021-03-31" unitRef="USD" xsi:nil="true" />
    <us-gaap:AvailableForSaleSecuritiesGrossRealizedGainLossNet contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">43232</us-gaap:AvailableForSaleSecuritiesGrossRealizedGainLossNet>
    <CLSN:ShelfRegistrationStatementAmount contextRef="From2018-09-01to2018-09-30" unitRef="USD" decimals="0">75000000</CLSN:ShelfRegistrationStatementAmount>
    <CLSN:ShelfRegistrationStatementAmount contextRef="From2021-03-18to2021-03-19" unitRef="USD" decimals="0">100000000</CLSN:ShelfRegistrationStatementAmount>
    <CLSN:AggregateOfferingPrices contextRef="From2018-12-02to2018-12-04_custom_CapitalOnDemandTMSalesAgreementMember" unitRef="USD" decimals="0">16000000</CLSN:AggregateOfferingPrices>
    <us-gaap:StockIssuedDuringPeriodSharesNewIssues contextRef="From2020-01-01to2020-03-31_us-gaap_CommonStockMember" unitRef="Shares" decimals="INF">5571428</us-gaap:StockIssuedDuringPeriodSharesNewIssues>
    <us-gaap:StockIssuedDuringPeriodSharesNewIssues contextRef="From2021-01-01to2021-03-31_us-gaap_CommonStockMember" unitRef="Shares" decimals="INF">33094085</us-gaap:StockIssuedDuringPeriodSharesNewIssues>
    <us-gaap:StockIssuedDuringPeriodSharesNewIssues contextRef="From2020-01-01to2020-12-31_custom_CapitalOnDemandAgreementMember" unitRef="Shares" decimals="INF">5200000</us-gaap:StockIssuedDuringPeriodSharesNewIssues>
    <us-gaap:StockIssuedDuringPeriodSharesNewIssues contextRef="From2020-02-26to2020-02-27_custom_SecuritiesPurchaseAgreementMember_us-gaap_SubsequentEventMember" unitRef="Shares" decimals="INF">4571428</us-gaap:StockIssuedDuringPeriodSharesNewIssues>
    <us-gaap:StockIssuedDuringPeriodSharesNewIssues contextRef="From2020-06-21to2020-06-22_custom_UnderwritingAgreementMember_custom_UnderwrittenOfferingMember" unitRef="Shares" decimals="INF">2666667</us-gaap:StockIssuedDuringPeriodSharesNewIssues>
    <us-gaap:StockIssuedDuringPeriodSharesNewIssues contextRef="From2020-09-07to2020-09-08_custom_LPCPurchaseAgreementMember_custom_LincolnParkCapitalFundLLCMember" unitRef="Shares" decimals="INF">26000000</us-gaap:StockIssuedDuringPeriodSharesNewIssues>
    <us-gaap:StockIssuedDuringPeriodSharesNewIssues contextRef="From2020-09-07to2020-09-08_custom_LPCPurchaseAgreementMember_custom_LincolnParkCapitalFundLLCMember_custom_LPCCommitmentSharesMember" unitRef="Shares" decimals="INF">437828</us-gaap:StockIssuedDuringPeriodSharesNewIssues>
    <us-gaap:StockIssuedDuringPeriodSharesNewIssues contextRef="From2021-01-01to2021-03-31_custom_CapitalOnDemandAgreementMember" unitRef="Shares" decimals="INF">7200000</us-gaap:StockIssuedDuringPeriodSharesNewIssues>
    <us-gaap:StockIssuedDuringPeriodSharesNewIssues contextRef="From2021-01-21to2021-01-22_custom_UnderwritingAgreementMember_custom_JanuaryRegisteredDirectOfferingMember" unitRef="Shares" decimals="INF">25925925</us-gaap:StockIssuedDuringPeriodSharesNewIssues>
    <us-gaap:StockIssuedDuringPeriodSharesNewIssues contextRef="From2021-03-30to2021-03-31_custom_UnderwritingAgreementMember_custom_MarchRegisteredDirectOfferingMember" unitRef="Shares" decimals="INF">11538462</us-gaap:StockIssuedDuringPeriodSharesNewIssues>
    <us-gaap:StockIssuedDuringPeriodSharesNewIssues contextRef="From2020-01-01to2020-12-31_custom_LPCPurchaseAgreementMember_custom_LincolnParkCapitalFundLLCMember" unitRef="Shares" decimals="INF">3300000</us-gaap:StockIssuedDuringPeriodSharesNewIssues>
    <us-gaap:SharesIssuedPricePerShare contextRef="AsOf2020-02-27_us-gaap_SubsequentEventMember_custom_SecuritiesPurchaseAgreementMember" unitRef="USDPShares" decimals="INF">1.05</us-gaap:SharesIssuedPricePerShare>
    <us-gaap:SharesIssuedPricePerShare contextRef="AsOf2020-06-22_custom_UnderwritingAgreementMember_custom_UnderwrittenOfferingMember" unitRef="USDPShares" decimals="INF">3.75</us-gaap:SharesIssuedPricePerShare>
    <us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight contextRef="AsOf2020-02-27_us-gaap_SubsequentEventMember_custom_SecuritiesPurchaseAgreementMember_custom_OriginalWarrantsMember" unitRef="Shares" decimals="INF">2971428</us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight>
    <us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight contextRef="AsOf2020-03-12_custom_ExchangeAgreementsMember_us-gaap_WarrantMember" unitRef="Shares" decimals="INF">3200000</us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight>
    <us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight contextRef="AsOf2021-03-31_srt_ScenarioForecastMember_custom_ExchangeAgreementsMember" unitRef="Shares" decimals="INF">1200000</us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight>
    <us-gaap:WarrantsAndRightsOutstandingTerm contextRef="AsOf2020-02-27_us-gaap_SubsequentEventMember_custom_SecuritiesPurchaseAgreementMember_custom_OriginalWarrantsMember">P5Y</us-gaap:WarrantsAndRightsOutstandingTerm>
    <us-gaap:WarrantsAndRightsOutstandingTerm contextRef="AsOf2020-03-12_custom_ExchangeAgreementsMember_us-gaap_WarrantMember">P5Y</us-gaap:WarrantsAndRightsOutstandingTerm>
    <us-gaap:ProceedsFromIssuanceOfWarrants contextRef="From2021-01-01to2021-03-31_srt_ScenarioForecastMember_custom_ExchangeAgreementsMember" unitRef="USD" decimals="0">1500000</us-gaap:ProceedsFromIssuanceOfWarrants>
    <us-gaap:SharePrice contextRef="AsOf2020-06-22_custom_UnderwritingAgreementMember_custom_UnderwrittenOfferingMember" unitRef="USDPShares" decimals="INF">3.4875</us-gaap:SharePrice>
    <us-gaap:SharePrice contextRef="AsOf2021-01-22_custom_UnderwritingAgreementMember_custom_JanuaryRegisteredDirectOfferingMember" unitRef="USDPShares" decimals="INF">1.35</us-gaap:SharePrice>
    <us-gaap:SharePrice contextRef="AsOf2021-03-31_custom_UnderwritingAgreementMember_custom_MarchRegisteredDirectOfferingMember" unitRef="USDPShares" decimals="INF">1.30</us-gaap:SharePrice>
    <CLSN:UnderwritingDiscountPricePerShare contextRef="From2020-06-21to2020-06-22_custom_UnderwritingAgreementMember_custom_UnderwrittenOfferingMember" unitRef="USDPShares" decimals="INF">0.2625</CLSN:UnderwritingDiscountPricePerShare>
    <CLSN:PercentageOfUnderwritingDiscountOnPublicOfferingPrice contextRef="From2020-06-21to2020-06-22_custom_UnderwritingAgreementMember_custom_UnderwrittenOfferingMember" unitRef="Percentage" decimals="INF">0.007</CLSN:PercentageOfUnderwritingDiscountOnPublicOfferingPrice>
    <CLSN:PlacementAgentFeeDescription contextRef="From2021-01-21to2021-01-22_custom_UnderwritingAgreementMember_custom_JanuaryRegisteredDirectOfferingMember">In connection with the January 2021 Offering, the Company entered into a placement agent agreement (the "January 2021 Placement Agent Agreement") with A.G.P./Alliance Global Partners (together with Brookline Capital Markets, the "January 2021 Placement Agents") 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>
    <CLSN:PlacementAgentFeeDescription contextRef="From2021-03-30to2021-03-31_custom_UnderwritingAgreementMember_custom_MarchRegisteredDirectOfferingMember">In connection with the March 2021 Offering, the Company entered into a placement agent agreement (the "March 2021 Placement Agent Agreement") with A.G.P./Alliance Global Partners, as lead placement agent ("AGP," and together with JonesTrading Institutional Services LLC and Brookline Capital Markets, a division of Arcadia Securities, LLC, serving as co-placement agents, the "March 2021 Placement Agents") 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>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized contextRef="AsOf2021-03-31_custom_TwoThousandAndEighteenStockIncentivePlanMember" unitRef="Shares" decimals="INF">2700000</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant contextRef="AsOf2021-03-31_custom_TwoThousandAndEighteenStockIncentivePlanMember_srt_MinimumMember" unitRef="Shares" decimals="INF">1200000</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant contextRef="AsOf2021-03-31_custom_TwoThousandAndEighteenStockIncentivePlanMember_srt_MaximumMember" unitRef="Shares" decimals="INF">3900000</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant contextRef="AsOf2020-06-15_custom_TwoThousandAndEighteenStockIncentivePlanMember_srt_MinimumMember" unitRef="Shares" decimals="INF">2500000</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant contextRef="AsOf2020-06-15_custom_TwoThousandAndEighteenStockIncentivePlanMember_srt_MaximumMember" unitRef="Shares" decimals="INF">6400000</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant>
    <CLSN:StockOptionsStrikePriceDescription contextRef="From2021-01-01to2021-03-31_custom_TwoThousandSevenStockIncentivePlanMember">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.</CLSN:StockOptionsStrikePriceDescription>
    <us-gaap:SharesIssued contextRef="AsOf2018-09-28_custom_InducementOptionGrantsMember_custom_FiveNewEmployeesMember_us-gaap_CommonStockMember" unitRef="Shares" decimals="INF">164004</us-gaap:SharesIssued>
    <us-gaap:SharesIssued contextRef="AsOf2019-02-19_custom_InducementOptionGrantsMember_custom_FiveNewEmployeesMember_us-gaap_CommonStockMember" unitRef="Shares" decimals="INF">140004</us-gaap:SharesIssued>
    <us-gaap:SharesIssued contextRef="AsOf2018-09-28_custom_InducementOptionGrantsMember_custom_FiveNewEmployeesMember_us-gaap_RestrictedStockMember" unitRef="Shares" decimals="INF">19000</us-gaap:SharesIssued>
    <us-gaap:SharesIssued contextRef="AsOf2019-02-19_custom_InducementOptionGrantsMember_custom_FiveNewEmployeesMember_us-gaap_RestrictedStockMember" unitRef="Shares" decimals="INF">13000</us-gaap:SharesIssued>
    <us-gaap:ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice contextRef="From2021-01-01to2021-03-31" unitRef="USDPShares" decimals="INF">2.24</us-gaap:ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice>
    <us-gaap:ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice contextRef="From2020-01-01to2020-03-31" unitRef="USDPShares" decimals="INF">1.01</us-gaap:ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice>
    <us-gaap:ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice contextRef="From2018-09-27to2018-09-28_custom_InducementOptionGrantsMember_custom_FiveNewEmployeesMember" unitRef="USDPShares" decimals="INF">2.77</us-gaap:ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice>
    <us-gaap:ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice contextRef="From2019-02-18to2019-02-19_custom_InducementOptionGrantsMember_custom_FiveNewEmployeesMember" unitRef="USDPShares" decimals="INF">2.18</us-gaap:ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice>
    <us-gaap:ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice contextRef="From2021-01-01to2021-03-31_us-gaap_EmployeeStockOptionMember" unitRef="USDPShares" decimals="INF">2.24</us-gaap:ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1 contextRef="From2018-09-27to2018-09-28_custom_InducementOptionGrantsMember_custom_FiveNewEmployeesMember">P3Y</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1 contextRef="From2019-02-18to2019-02-19_custom_InducementOptionGrantsMember_custom_FiveNewEmployeesMember">P3Y</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1>
    <us-gaap:CommonStockCapitalSharesReservedForFutureIssuance contextRef="AsOf2021-03-31_custom_EquityStockAwardsMember_custom_GrantedUnderTwoThousandEighteenPlanAndTwoThousandSevenPlanMember" unitRef="Shares" decimals="INF">6420825</us-gaap:CommonStockCapitalSharesReservedForFutureIssuance>
    <us-gaap:CommonStockCapitalSharesReservedForFutureIssuance contextRef="AsOf2020-12-31_custom_TwoThousandAndEighteenPlanMember" unitRef="Shares" decimals="INF">77599</us-gaap:CommonStockCapitalSharesReservedForFutureIssuance>
    <us-gaap:CommonStockCapitalSharesReservedForFutureIssuance contextRef="AsOf2020-12-31_custom_InducementAwardsMember" unitRef="Shares" decimals="INF">140004</us-gaap:CommonStockCapitalSharesReservedForFutureIssuance>
    <us-gaap:CommonStockCapitalSharesReservedForFutureIssuance contextRef="AsOf2021-03-31_custom_TwoThousandAndEighteenStockIncentivePlanMember" unitRef="Shares" decimals="INF">6498424</us-gaap:CommonStockCapitalSharesReservedForFutureIssuance>
    <us-gaap:AllocatedShareBasedCompensationExpense contextRef="From2021-01-01to2021-03-31_custom_EmployeeStockOptionAndRestrictedStockAwardsMember" unitRef="USD" decimals="0">1600000</us-gaap:AllocatedShareBasedCompensationExpense>
    <us-gaap:AllocatedShareBasedCompensationExpense contextRef="From2020-01-01to2020-03-31_custom_EmployeeStockOptionAndRestrictedStockAwardsMember" unitRef="USD" decimals="0">500000</us-gaap:AllocatedShareBasedCompensationExpense>
    <us-gaap:AllocatedShareBasedCompensationExpense contextRef="From2021-01-01to2021-03-31_custom_EmployeeStockOptionAndRestrictedStockAwardsMember_us-gaap_ResearchAndDevelopmentExpenseMember" unitRef="USD" decimals="0">587507</us-gaap:AllocatedShareBasedCompensationExpense>
    <us-gaap:AllocatedShareBasedCompensationExpense contextRef="From2020-01-01to2020-03-31_custom_EmployeeStockOptionAndRestrictedStockAwardsMember_us-gaap_ResearchAndDevelopmentExpenseMember" unitRef="USD" decimals="0">177936</us-gaap:AllocatedShareBasedCompensationExpense>
    <us-gaap:AllocatedShareBasedCompensationExpense contextRef="From2021-01-01to2021-03-31_custom_EmployeeStockOptionAndRestrictedStockAwardsMember_us-gaap_GeneralAndAdministrativeExpenseMember" unitRef="USD" decimals="0">991819</us-gaap:AllocatedShareBasedCompensationExpense>
    <us-gaap:AllocatedShareBasedCompensationExpense contextRef="From2020-01-01to2020-03-31_custom_EmployeeStockOptionAndRestrictedStockAwardsMember_us-gaap_GeneralAndAdministrativeExpenseMember" unitRef="USD" decimals="0">274029</us-gaap:AllocatedShareBasedCompensationExpense>
    <us-gaap:EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">4100000</us-gaap:EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized>
    <us-gaap:EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1 contextRef="From2021-01-01to2021-03-31">P1Y3M19D</us-gaap:EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1>
    <us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2 contextRef="From2021-01-01to2021-03-31_us-gaap_EmployeeStockOptionMember">P8Y</us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2>
    <us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1 contextRef="From2021-01-01to2021-03-31_us-gaap_EmployeeStockOptionMember">P7Y9M18D</us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum contextRef="From2021-01-01to2021-03-31" unitRef="Percentage" decimals="INF">0.0164</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum contextRef="From2021-01-01to2021-03-31" unitRef="Percentage" decimals="INF">0.0174</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMinimum contextRef="From2021-01-01to2021-03-31" unitRef="Percentage" decimals="INF">1.068</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMinimum>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum contextRef="From2021-01-01to2021-03-31" unitRef="Percentage" decimals="INF">1.125</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum>
    <us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1 contextRef="From2020-01-01to2020-03-31">P8Y6M</us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1>
    <us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1 contextRef="From2021-01-01to2021-03-31_srt_MinimumMember">P7Y6M</us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1>
    <us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1 contextRef="From2021-01-01to2021-03-31_srt_MaximumMember">P10Y</us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate contextRef="From2021-01-01to2021-03-31" unitRef="Percentage" decimals="INF">0.000</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate contextRef="From2020-01-01to2020-03-31" unitRef="Percentage" decimals="INF">0.000</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate contextRef="From2020-01-01to2020-03-31" unitRef="Percentage" decimals="INF">0.0133</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate contextRef="From2020-01-01to2020-03-31" unitRef="Percentage" decimals="INF">1.027</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate>
    <us-gaap:BusinessCombinationConsiderationTransferredLiabilitiesIncurred contextRef="From2021-01-01to2021-03-31_custom_EGWCMember_custom_FairValueEarnoutMilestoneLiabilityMember" unitRef="USD" decimals="0">7200000</us-gaap:BusinessCombinationConsiderationTransferredLiabilitiesIncurred>
    <us-gaap:BusinessCombinationConsiderationTransferredLiabilitiesIncurred contextRef="From2020-01-01to2020-12-31_custom_EGWCMember_custom_FairValueEarnoutMilestoneLiabilityMember" unitRef="USD" decimals="0">7000000</us-gaap:BusinessCombinationConsiderationTransferredLiabilitiesIncurred>
    <us-gaap:BusinessCombinationConsiderationTransferredLiabilitiesIncurred contextRef="From2020-01-01to2020-03-31_custom_EGWCMember_custom_FairValueEarnoutMilestoneLiabilityMember" unitRef="USD" decimals="0">5800000</us-gaap:BusinessCombinationConsiderationTransferredLiabilitiesIncurred>
    <us-gaap:BusinessCombinationConsiderationTransferredLiabilitiesIncurred contextRef="From2019-01-01to2019-12-31_custom_EGWCMember_custom_FairValueEarnoutMilestoneLiabilityMember" unitRef="USD" decimals="0">5700000</us-gaap:BusinessCombinationConsiderationTransferredLiabilitiesIncurred>
    <CLSN:EarnoutMilestoneLiability1 contextRef="AsOf2019-03-28_custom_EGENIncMember_custom_AmendedAssetPurchaseAgreementMember_custom_AchievingMilestoneWithInOneYearMember" unitRef="USD" decimals="0">12400000</CLSN:EarnoutMilestoneLiability1>
    <CLSN:EarnoutMilestoneLiability1 contextRef="AsOf2019-03-28_custom_EGENIncMember_custom_AmendedAssetPurchaseAgreementMember_custom_CertainBusinessDaysOfAchievingMilestoneMember" unitRef="USD" decimals="0">7000000</CLSN:EarnoutMilestoneLiability1>
    <CLSN:EarnoutMilestoneLiability1 contextRef="AsOf2019-03-28_custom_EGENIncMember_custom_AmendedAssetPurchaseAgreementMember" unitRef="USD" decimals="0">12400000</CLSN:EarnoutMilestoneLiability1>
    <CLSN:GainLossFromChangeInFairValueOfEarnOutMilestoneLiability contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">-151000</CLSN:GainLossFromChangeInFairValueOfEarnOutMilestoneLiability>
    <CLSN:EarnoutMilestoneLiability contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">-7169000</CLSN:EarnoutMilestoneLiability>
    <CLSN:EarnoutMilestoneLiability contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">-7018000</CLSN:EarnoutMilestoneLiability>
    <CLSN:EarnoutPaymentOptionsDescription contextRef="From2021-01-01to2021-03-31_custom_EGWCMember">In assessing the earnout milestone liability at March 31, 2021, the Company fair valued each of the two payment options per the Amended Asset Purchase Agreement and weighted them at 50% and 50% probability for the $7.0 million and the $12.4 million payments, respectively.</CLSN:EarnoutPaymentOptionsDescription>
    <CLSN:EarnoutPaymentOptionsDescription contextRef="From2020-01-01to2020-03-31_custom_EGWCMember">In assessing the earnout milestone liability at March 31, 2020, the Company fair valued each of the two payment options per the Amended Asset Purchase Agreement and weighted them at 80% and 20% probability for the $7.0 million and the $12.4 million payments, respectively.</CLSN:EarnoutPaymentOptionsDescription>
    <CLSN:NoncashChargeOnEarnourMilestoneLiability contextRef="From2021-01-01to2021-03-31_custom_EGWCMember" unitRef="USD" decimals="0">200000</CLSN:NoncashChargeOnEarnourMilestoneLiability>
    <CLSN:NoncashChargeOnEarnourMilestoneLiability contextRef="From2020-01-01to2020-03-31_custom_EGWCMember" unitRef="USD" decimals="0">100000</CLSN:NoncashChargeOnEarnourMilestoneLiability>
    <CLSN:EstimatedTimeToAchieveMileStone contextRef="From2020-01-01to2020-12-31_srt_MinimumMember">P0Y6M14D</CLSN:EstimatedTimeToAchieveMileStone>
    <CLSN:EstimatedTimeToAchieveMileStone contextRef="From2020-01-01to2020-12-31_srt_MaximumMember">P1Y6M14D</CLSN:EstimatedTimeToAchieveMileStone>
    <CLSN:EstimatedTimeToAchieveMileStone contextRef="From2019-01-01to2019-12-31_srt_MinimumMember">P1Y1M13D</CLSN:EstimatedTimeToAchieveMileStone>
    <CLSN:EstimatedTimeToAchieveMileStone contextRef="From2019-01-01to2019-12-31_srt_MaximumMember">P2Y1M13D</CLSN:EstimatedTimeToAchieveMileStone>
    <CLSN:EstimatedTimeToAchieveMileStone contextRef="From2021-01-01to2021-03-31_srt_MinimumMember">P0Y3M15D</CLSN:EstimatedTimeToAchieveMileStone>
    <CLSN:EstimatedTimeToAchieveMileStone contextRef="From2021-01-01to2021-03-31_srt_MaximumMember">P1Y3M15D</CLSN:EstimatedTimeToAchieveMileStone>
    <CLSN:EstimatedTimeToAchieveMileStone contextRef="From2020-01-01to2020-03-31_srt_MinimumMember">P1Y0M15D</CLSN:EstimatedTimeToAchieveMileStone>
    <CLSN:EstimatedTimeToAchieveMileStone contextRef="From2020-01-01to2020-03-31_srt_MaximumMember">P2Y0M15D</CLSN:EstimatedTimeToAchieveMileStone>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber contextRef="AsOf2021-03-31" unitRef="Shares" decimals="INF">2636899</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber contextRef="AsOf2020-12-31" unitRef="Shares" decimals="INF">3853566</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExercised contextRef="From2021-01-01to2021-03-31" unitRef="Shares" decimals="INF">1216667</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExercised>
    <CLSN:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingWeightedAverageExercisePrice contextRef="AsOf2021-03-31" unitRef="USDPShares" decimals="INF">1.40</CLSN:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingWeightedAverageExercisePrice>
    <CLSN:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingWeightedAverageExercisePrice contextRef="AsOf2020-12-31" unitRef="USDPShares" decimals="INF">1.35</CLSN:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingWeightedAverageExercisePrice>
    <CLSN:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExerciseInPeriodWeightedAverageExercisePrice contextRef="From2021-01-01to2021-03-31" unitRef="USDPShares" decimals="INF">1.24</CLSN:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExerciseInPeriodWeightedAverageExercisePrice>
    <CLSN:SharebasedCompensationArrangementBySharebasedPaymentAwardNonOptionsOutstandingWeightedAverageRemainingContractualTerm2 contextRef="From2021-01-01to2021-03-31">P4Y7M6D</CLSN:SharebasedCompensationArrangementBySharebasedPaymentAwardNonOptionsOutstandingWeightedAverageRemainingContractualTerm2>
    <CLSN:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionsOutstandingIntrinsicValue contextRef="AsOf2020-12-31" unitRef="USD" decimals="0">413500</CLSN:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionsOutstandingIntrinsicValue>
    <us-gaap:AreaOfLand contextRef="AsOf2011-07-31" unitRef="Sqft" decimals="INF">10870</us-gaap:AreaOfLand>
    <us-gaap:AreaOfLand contextRef="AsOf2020-12-31_custom_HuntsvilleAlabamaMember" unitRef="Sqft" decimals="INF">11500</us-gaap:AreaOfLand>
    <us-gaap:LeaseExpirationDate1 contextRef="From2011-07-01to2011-07-31">2017-04-30</us-gaap:LeaseExpirationDate1>
    <us-gaap:LesseeOperatingLeaseTermOfContract contextRef="AsOf2011-07-31">P66M</us-gaap:LesseeOperatingLeaseTermOfContract>
    <us-gaap:LesseeOperatingLeaseRenewalTerm contextRef="AsOf2011-07-31">P64M</us-gaap:LesseeOperatingLeaseRenewalTerm>
    <us-gaap:LesseeOperatingLeaseOptionToExtend contextRef="From2011-07-01to2011-07-31">The 1st 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 $18,900 in the first year to approximately $20,500 in the final year of the 1st Lease Amendment. The Company also had a one-time option to cancel the lease as of the 40th month after the commencement date of the 1st Lease Amendment and must provide the landlord notice by the 28th month of the lease. Effective January 9, 2019, the Company amended the current terms of the 1st 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. In conjunction with this 2nd Lease Amendment, we agreed to modify our one-time option to cancel the lease as of the end of August 2021 and we must provide notice to the landlord by the end of August 2020. The monthly rent will range from approximately $25,035 in the first year to approximately $27,088 in the final year of the 2nd Lease Amendment.</us-gaap:LesseeOperatingLeaseOptionToExtend>
    <us-gaap:PaymentsForRent contextRef="From2021-01-01to2021-03-31_custom_FirstLeaseAmendmentMember_custom_FirstYearMember" unitRef="USD" decimals="0">18900</us-gaap:PaymentsForRent>
    <us-gaap:PaymentsForRent contextRef="From2021-01-01to2021-03-31_custom_FirstLeaseAmendmentMember_custom_FinalYearMember" unitRef="USD" decimals="0">20500</us-gaap:PaymentsForRent>
    <us-gaap:PaymentsForRent contextRef="From2021-01-01to2021-03-31_custom_SecondLeaseAmendmentMember_custom_FirstYearMember" unitRef="USD" decimals="0">25035</us-gaap:PaymentsForRent>
    <us-gaap:PaymentsForRent contextRef="From2021-01-01to2021-03-31_custom_SecondLeaseAmendmentMember_custom_FinalYearMember" unitRef="USD" decimals="0">27088</us-gaap:PaymentsForRent>
    <us-gaap:PaymentsForRent contextRef="From2018-01-01to2018-01-31_custom_EGENAssetPurchaseAgreementMember" unitRef="USD" decimals="0">18100</us-gaap:PaymentsForRent>
    <us-gaap:LesseeOperatingLeaseDescription contextRef="From2011-07-01to2011-07-31">In 2011, the Company executed a lease (the "Lease") with Brandywine Operating Partnership, L.P. (Brandywine), a Delaware limited partnership for a 10,870 square foot premises located in Lawrenceville, New Jersey and relocated its offices to Lawrenceville, New Jersey from Columbia, Maryland.</us-gaap:LesseeOperatingLeaseDescription>
    <us-gaap:LesseeOperatingLeaseDescription contextRef="From2018-01-01to2018-01-31_custom_EGENAssetPurchaseAgreementMember">In connection with the EGEN Asset Purchase Agreement in June 2014, the Company assumed the existing lease with another landlord for an 11,500 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 $18,100 per month.</us-gaap:LesseeOperatingLeaseDescription>
    <us-gaap:OperatingLeaseLiability contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">1040183</us-gaap:OperatingLeaseLiability>
    <us-gaap:OperatingLeaseLiability contextRef="AsOf2019-01-02" unitRef="USD" decimals="0">1900000</us-gaap:OperatingLeaseLiability>
    <us-gaap:OperatingLeaseLiability contextRef="AsOf2019-01-02_us-gaap_AccountingStandardsUpdate201602Member" unitRef="USD" decimals="0">1500000</us-gaap:OperatingLeaseLiability>
    <us-gaap:OtherLiabilities contextRef="AsOf2019-01-02_us-gaap_AccountingStandardsUpdate201602Member" unitRef="USD" decimals="0">100000</us-gaap:OtherLiabilities>
    <us-gaap:RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability contextRef="From2018-12-30to2019-01-02" unitRef="USD" decimals="0">1800000</us-gaap:RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability>
    <us-gaap:OperatingLeaseCost contextRef="From2021-01-01to2021-03-31_custom_OperatingLeasesMember" unitRef="USD" decimals="0">130595</us-gaap:OperatingLeaseCost>
    <us-gaap:OperatingLeaseCost contextRef="From2020-01-01to2020-03-31_custom_OperatingLeasesMember" unitRef="USD" decimals="0">130595</us-gaap:OperatingLeaseCost>
    <us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">398872</us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths>
    <us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">535579</us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo>
    <us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">1167567</us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue>
    <us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">127384</us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount>
    <us-gaap:OperatingLeaseWeightedAverageRemainingLeaseTerm1 contextRef="AsOf2021-03-31">P2Y2M12D</us-gaap:OperatingLeaseWeightedAverageRemainingLeaseTerm1>
    <us-gaap:OperatingLeaseWeightedAverageDiscountRatePercent contextRef="AsOf2021-03-31" unitRef="Percentage" decimals="INF">0.0998</us-gaap:OperatingLeaseWeightedAverageDiscountRatePercent>
    <us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">233116</us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree>
    <CLSN:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearThreeAndThereAfter contextRef="AsOf2021-03-31" unitRef="USD" xsi:nil="true" />
    <us-gaap:ProceedsFromLicenseFeesReceived contextRef="From2013-01-17to2013-01-18_custom_HisunMember" unitRef="USD" decimals="0">5000000</us-gaap:ProceedsFromLicenseFeesReceived>
    <us-gaap:DeferredRevenue contextRef="AsOf2013-01-18_custom_HisunMember" unitRef="USD" decimals="0">5000000</us-gaap:DeferredRevenue>
    <CLSN:DeferredRevenueAmortizationPeriod contextRef="From2013-01-17to2013-01-18_custom_HisunMember">P10Y</CLSN:DeferredRevenueAmortizationPeriod>
    <CLSN:UpfrontPaymentBeingRecognized contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">5000000</CLSN:UpfrontPaymentBeingRecognized>
    <us-gaap:LitigationSettlementExpense contextRef="From2020-04-22to2020-04-24" unitRef="USD" decimals="0">187500</us-gaap:LitigationSettlementExpense>
    <us-gaap:PaymentsForLegalSettlements contextRef="From2020-10-01to2020-10-02_us-gaap_SubsequentEventMember" unitRef="USD" decimals="0">187500</us-gaap:PaymentsForLegalSettlements>
    <us-gaap:SaleOfStockNumberOfSharesIssuedInTransaction contextRef="From2021-04-04to2021-04-05_us-gaap_SubsequentEventMember" unitRef="Shares" decimals="INF">11500000</us-gaap:SaleOfStockNumberOfSharesIssuedInTransaction>
    <us-gaap:SaleOfStockConsiderationReceivedOnTransaction contextRef="From2021-04-04to2021-04-05_us-gaap_SubsequentEventMember" unitRef="USD" decimals="0">15000000</us-gaap:SaleOfStockConsiderationReceivedOnTransaction>
    <CLSN:RiskadjustmentAssessmentOfAchievingMilestone contextRef="From2021-01-01to2021-03-31" unitRef="Percentage" decimals="INF">0.80</CLSN:RiskadjustmentAssessmentOfAchievingMilestone>
    <CLSN:RiskadjustmentAssessmentOfAchievingMilestone contextRef="From2020-01-01to2020-03-31" unitRef="Percentage" decimals="INF">0.80</CLSN:RiskadjustmentAssessmentOfAchievingMilestone>
    <CLSN:RiskadjustmentAssessmentOfAchievingMilestone contextRef="From2019-01-01to2019-12-31" unitRef="Percentage" decimals="INF">0.80</CLSN:RiskadjustmentAssessmentOfAchievingMilestone>
    <CLSN:RiskadjustmentAssessmentOfAchievingMilestone contextRef="From2020-01-01to2020-12-31" unitRef="Percentage" decimals="INF">0.80</CLSN:RiskadjustmentAssessmentOfAchievingMilestone>
    <CLSN:DiscountRatesOnMileStoneLiabilities contextRef="From2021-01-01to2021-03-31" unitRef="Percentage" decimals="INF">0.09</CLSN:DiscountRatesOnMileStoneLiabilities>
    <CLSN:DiscountRatesOnMileStoneLiabilities contextRef="From2020-01-01to2020-03-31" unitRef="Percentage" decimals="INF">0.09</CLSN:DiscountRatesOnMileStoneLiabilities>
    <CLSN:DiscountRatesOnMileStoneLiabilities contextRef="From2019-01-01to2019-12-31" unitRef="Percentage" decimals="INF">0.09</CLSN:DiscountRatesOnMileStoneLiabilities>
    <CLSN:DiscountRatesOnMileStoneLiabilities contextRef="From2020-01-01to2020-12-31" unitRef="Percentage" decimals="INF">0.09</CLSN:DiscountRatesOnMileStoneLiabilities>
    <us-gaap:InterestPaidNet contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">120313</us-gaap:InterestPaidNet>
    <us-gaap:InterestPaidNet contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">243299</us-gaap:InterestPaidNet>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber contextRef="AsOf2020-12-31_us-gaap_EmployeeStockOptionMember" unitRef="Shares" decimals="INF">4624725</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber contextRef="AsOf2021-03-31_us-gaap_EmployeeStockOptionMember" unitRef="Shares" decimals="INF">6557079</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod contextRef="From2021-01-01to2021-03-31_us-gaap_EmployeeStockOptionMember" unitRef="Shares" decimals="INF">2032500</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod>
    <us-gaap:StockIssuedDuringPeriodSharesStockOptionsExercised contextRef="From2021-01-01to2021-03-31_us-gaap_CommonStockMember" unitRef="Shares" decimals="INF">7500</us-gaap:StockIssuedDuringPeriodSharesStockOptionsExercised>
    <us-gaap:StockIssuedDuringPeriodSharesStockOptionsExercised contextRef="From2021-01-01to2021-03-31_us-gaap_EmployeeStockOptionMember" unitRef="Shares" decimals="INF">7500</us-gaap:StockIssuedDuringPeriodSharesStockOptionsExercised>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod contextRef="From2021-01-01to2021-03-31_us-gaap_EmployeeStockOptionMember" unitRef="Shares" decimals="INF">92646</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber contextRef="AsOf2021-03-31_us-gaap_EmployeeStockOptionMember" unitRef="Shares" decimals="INF">4063706</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice contextRef="AsOf2020-12-31_us-gaap_EmployeeStockOptionMember" unitRef="USDPShares" decimals="INF">2.77</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice contextRef="AsOf2021-03-31_us-gaap_EmployeeStockOptionMember" unitRef="USDPShares" decimals="INF">2.65</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice>
    <us-gaap:ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice contextRef="From2021-01-01to2021-03-31_us-gaap_EmployeeStockOptionMember" unitRef="USDPShares" decimals="INF">0.63</us-gaap:ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice contextRef="From2021-01-01to2021-03-31_us-gaap_EmployeeStockOptionMember" unitRef="USDPShares" decimals="INF">2.69</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice contextRef="AsOf2021-03-31_us-gaap_EmployeeStockOptionMember" unitRef="USDPShares" decimals="INF">2.70</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue contextRef="AsOf2021-03-31_us-gaap_EmployeeStockOptionMember" unitRef="USD" decimals="0">13163</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue>
    <us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1 contextRef="AsOf2021-03-31_us-gaap_EmployeeStockOptionMember" unitRef="USD" decimals="0">3300</us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber contextRef="AsOf2020-12-31_us-gaap_RestrictedStockMember" unitRef="Shares" decimals="INF">2750</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber contextRef="AsOf2021-03-31_us-gaap_RestrictedStockMember" unitRef="Shares" decimals="INF">3750</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod contextRef="From2021-01-01to2021-03-31_us-gaap_RestrictedStockMember" unitRef="Shares" decimals="INF">1000</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod contextRef="From2021-01-01to2021-03-31_us-gaap_RestrictedStockMember" unitRef="Shares" xsi:nil="true" />
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod contextRef="From2021-01-01to2021-03-31_us-gaap_RestrictedStockMember" unitRef="Shares" xsi:nil="true" />
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue contextRef="AsOf2020-12-31_us-gaap_RestrictedStockMember" unitRef="USDPShares" decimals="INF">0.89</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue contextRef="AsOf2021-03-31_us-gaap_RestrictedStockMember" unitRef="USDPShares" decimals="INF">1.31</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue contextRef="From2021-01-01to2021-03-31_us-gaap_RestrictedStockMember" unitRef="USDPShares" decimals="INF">2.22</us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue>
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue contextRef="From2021-01-01to2021-03-31_us-gaap_RestrictedStockMember" unitRef="USDPShares" xsi:nil="true" />
    <us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue contextRef="From2021-01-01to2021-03-31_us-gaap_RestrictedStockMember" unitRef="USDPShares" xsi:nil="true" />
    <us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueOutstanding contextRef="AsOf2021-03-31_us-gaap_RestrictedStockMember" unitRef="USD" decimals="0">7875</us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueOutstanding>
    <us-gaap:ScheduleOfStockholdersEquityNoteWarrantsOrRightsTextBlock contextRef="From2021-01-01to2021-03-31">&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Following is a summary of all warrant activity for&#13;the three months ended March 31, 2021:&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="font: 12pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&lt;font style="font-size: 10pt"&gt;Warrants&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Number of&lt;br /&gt;&#13;    Warrants&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Issued&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Weighted&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Average&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Exercise Price&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="width: 58%"&gt;&lt;font style="font-size: 10pt"&gt;Warrants outstanding at December 31, 2020&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 18%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;3,853,566&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 18%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1.35&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Warrants exercised during the three months ended March 31, 2021 (see Note 11)&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;(1,216,667&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;)&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1.24&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Warrants outstanding at March 31, 2021&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;2,636,899&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1.40&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Aggregate intrinsic value of outstanding warrants at March 31, 2021&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;413,500&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Weighted average remaining contractual terms at March 31, 2021&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;4.6 years&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;</us-gaap:ScheduleOfStockholdersEquityNoteWarrantsOrRightsTextBlock>
    <CLSN:SummaryOfStockOptionAndRestrictedStockAwardsTableTextBlock contextRef="From2021-01-01to2021-03-31">&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;A summary of stock option awards and restricted stock&#13;grants for the three-months ended March 31, 2021 is presented below:&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="font: 12pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="6" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Stock Options&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="6" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Restricted Stock Awards&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Weighted&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Average&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Options&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Outstanding&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Weighted&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Average&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Exercise&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Price&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Non-vested&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Restricted&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Stock&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Outstanding&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Weighted&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Average&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Grant&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Date&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Fair Value&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Contractual&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Terms of&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Equity&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Awards&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;(in years)&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="width: 40%"&gt;&lt;font style="font-size: 10pt"&gt;Equity awards outstanding at January 1, 2021&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 9%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;4,624,725&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 9%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;2.77&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 9%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;2,750&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 9%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;0.89&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 9%; text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Equity awards granted&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;2,032,500&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;2.24&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1,000&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;2.22&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Equity awards exercised or vested and issued&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;(7,500&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;)&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;0.63&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Equity awards forfeited, cancelled or expired&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;(92,646&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;)&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;2.69&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Equity awards outstanding at March 31, 2021&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;6,557,079&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;2.65&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;3,750&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1.31&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;8.0&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Aggregate intrinsic value of outstanding equity awards at March 31, 2021&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;13,163&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;7,875&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Equity awards exercisable at March 31, 2021&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;4,063,706&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;2.70&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;7.8&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Aggregate intrinsic value of equity awards exercisable at March 31, 2021&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;3,300&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;</CLSN:SummaryOfStockOptionAndRestrictedStockAwardsTableTextBlock>
    <us-gaap:ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock contextRef="From2021-01-01to2021-03-31">&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;The Company used the following assumptions for determining&#13;the fair value of options granted under the Black-Scholes option pricing model:&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="font: 12pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="6" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Three Months Ended March 31,&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;2021&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;2020&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="width: 58%"&gt;&lt;font style="font-size: 10pt"&gt;Risk-free interest rate&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 18%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1.64 to 1.74&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;%&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 18%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1.33&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;%&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Expected volatility&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;106.8 to 112.5&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;%&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;102.7&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;%&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Expected life (in years)&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;7.5 to 10.0&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;8.5&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Expected dividend yield&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;%&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;%&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;</us-gaap:ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock>
    <us-gaap:ScheduleOfAccruedLiabilitiesTableTextBlock contextRef="From2021-01-01to2021-03-31">&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Other accrued liabilities at March 31, 2021 and December&#13;31, 2020 include the following:&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="font: 12pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td style="text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;March 31, 2021&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;December 31, 2020&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td style="text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="width: 62%"&gt;&lt;font style="font-size: 10pt"&gt;Amounts due to contract research organizations and other contractual agreements&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 16%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;855,517&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 16%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;636,000&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Accrued payroll and related benefits&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;790,111&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1,736,271&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Accrued professional fees&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;138,430&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;66,850&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Other&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;19,411&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;19,411&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Total&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1,803,469&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;2,458,532&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;</us-gaap:ScheduleOfAccruedLiabilitiesTableTextBlock>
    <us-gaap:ScheduleofFiniteLivedIntangibleAssetsFutureAmortizationExpenseTableTextBlock contextRef="From2021-01-01to2021-03-31">&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Following is a schedule of future amortization amounts&#13;during the remaining life of the Covenant Not to Compete.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="font: 12pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Year Ended&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;March 31, 2021&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="width: 79%"&gt;&lt;font style="font-size: 10pt"&gt;2022&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 18%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;56,831&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;2023 and thereafter&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; padding-left: 10pt"&gt;&lt;font style="font-size: 10pt"&gt;Total&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;56,831&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;</us-gaap:ScheduleofFiniteLivedIntangibleAssetsFutureAmortizationExpenseTableTextBlock>
    <us-gaap:FiniteLivedAndIndefiniteLivedIntangibleAssetsAcquiredAsPartOfBusinessCombinationTableTextBlock contextRef="From2021-01-01to2021-03-31">&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Following is a summary of the net fair value of the&#13;assets acquired in the EGEN asset acquisition for the three-month period ended March 31, 2021:&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="font: 12pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td style="text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;IPR&amp;#38;D&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;Goodwill&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;Covenant Not To Compete&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;For the three-months ended March 31, 2021&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="width: 51%"&gt;&lt;font style="font-size: 10pt"&gt;Balance at January 1, 2021, net&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 13%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;13,366,234&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 13%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1,976,101&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 14%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;113,660&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Amortization&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;(56,829&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;)&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Balance at March 31, 2021, net&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;13,366,234&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1,976,101&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;56,831&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;</us-gaap:FiniteLivedAndIndefiniteLivedIntangibleAssetsAcquiredAsPartOfBusinessCombinationTableTextBlock>
    <us-gaap:ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock contextRef="From2021-01-01to2021-03-31">&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Assets and liabilities measured at fair value are&#13;summarized below:&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="font: 12pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td style="text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Total Fair Value&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1)&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Significant Other Observable Inputs&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;(Level 2)&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Significant Unobservable Inputs&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;(Level 3)&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Assets:&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Recurring items as of March 31, 2021&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="width: 46%; padding-left: 10pt"&gt;&lt;font style="font-size: 10pt"&gt;Corporate debt securities, available for sale&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 11%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;15,000,045&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 10%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;&amp;#8211;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 10%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;15,000,045&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 11%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;&amp;#8211;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Non-recurring items as of March 31, 2021&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-left: 10pt"&gt;&lt;font style="font-size: 10pt"&gt;In-process R&amp;#38;D (Note 8)&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;13,366,234&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;&amp;#8211;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;&amp;#8211;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;13,366,234&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Non-recurring items as of December 31, 2020&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="padding-left: 10pt"&gt;&lt;font style="font-size: 10pt"&gt;In-process R&amp;#38;D (Note 8)&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;13,366,234&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;&amp;#8211;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;&amp;#8211;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;13,366,234&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Liabilities:&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Recurring items as of March 31, 2021&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-left: 10pt"&gt;&lt;font style="font-size: 10pt"&gt;Earn-out milestone liability (Note 13)&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;7,169,000&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;&amp;#8211;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;&amp;#8211;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;7,169,000&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Recurring items as of December 31, 2020&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="padding-left: 10pt"&gt;&lt;font style="font-size: 10pt"&gt;Earn-out milestone liability (Note 13)&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;7,018,000&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;&amp;#8211;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;&amp;#8211;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;7,018,000&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;</us-gaap:ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock>
    <us-gaap:ScheduleOfUnrealizedLossOnInvestmentsTableTextBlock contextRef="From2021-01-01to2021-03-31">&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;The following table shows the Company&amp;#8217;s investment&#13;in debt securities available for sale gross unrealized gains (losses) and fair value by investment category and length of time that individual&#13;securities have been in a continuous unrealized loss position at March 31, 2021 and December 31, 2020. The Company has reviewed individual&#13;securities to determine whether a decline in fair value below the amortizable cost basis is other than temporary.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="font: 12pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td style="text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="6" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;March 31, 2021&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="6" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;December 31, 2020&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Available for sale securities (all unrealized holding gains and losses are less than 12 months at date of measurement)&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Fair Value&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Unrealized Holding&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Gains (Losses)&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Fair Value&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Unrealized Holding&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Gains (Losses)&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="width: 44%; padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Investments in debt securities with unrealized gains&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%; padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; width: 11%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;15,000,045&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%; padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%; padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; width: 11%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1,785&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%; padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%; padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; width: 11%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%; padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%; padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; width: 11%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%; padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; padding-left: 10pt"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Total&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;15,000,045&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1,785&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;</us-gaap:ScheduleOfUnrealizedLossOnInvestmentsTableTextBlock>
    <us-gaap:InvestmentIncomeTextBlock contextRef="From2021-01-01to2021-03-31">&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Investment income, which includes net realized losses&#13;on sales of available for sale securities and investment income interest and dividends, is summarized as follows:&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="font: 12pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td style="text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="6" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Three Months Ended &lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;March 31,&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td style="text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;2021&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;2020&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="width: 62%"&gt;&lt;font style="font-size: 10pt"&gt;Interest and dividends accrued and paid&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 16%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;2,411&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 16%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;45,077&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Realized gains&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;&amp;#8211;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;43,232&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Investment income net&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;2,411&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;88,309&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;</us-gaap:InvestmentIncomeTextBlock>
    <us-gaap:SubsequentEventsTextBlock contextRef="From2021-01-01to2021-03-31">&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;b&gt;Note 18. Subsequent Events&lt;/b&gt;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;As more fully discussed in Note 11, the Company completed&#13;the sale of 11.5 million shares of common stock for gross proceeds of $15 million on April 5, 2021.&lt;/p&gt;</us-gaap:SubsequentEventsTextBlock>
    <CLSN:LicensingTransactionTextBlock contextRef="From2021-01-01to2021-03-31">&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;b&gt;Note 16. Technology Development and Licensing Agreements&lt;/b&gt;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;On May 7, 2012, the Company entered into a long-term&#13;commercial supply agreement with Zhejiang Hisun Pharmaceutical Co. Ltd. (Hisun) for the production of ThermoDox&lt;sup&gt;&amp;#174;&lt;/sup&gt; in the&#13;China territory. In accordance with the terms of the agreement, Hisun will be responsible for providing all of the technical and regulatory&#13;support services, including the costs of all technical transfer, registration and bioequivalence studies, technical transfer costs, Celsion&#13;consultative support costs and the purchase of any necessary equipment and additional facility costs necessary to support capacity requirements&#13;for the manufacture of ThermoDox&lt;sup&gt;&amp;#174;&lt;/sup&gt;. Celsion will repay Hisun for the aggregate amount of these development costs and fees&#13;commencing on the successful completion of three registration batches of ThermoDox&lt;sup&gt;&amp;#174;&lt;/sup&gt;. Hisun is also obligated to certain&#13;performance requirements under the agreement. The agreement will initially be limited to a percentage of the production requirements of&#13;ThermoDox&lt;sup&gt;&amp;#174;&lt;/sup&gt; in the China territory with Hisun retaining an option for additional global supply after local regulatory approval&#13;in the China territory. In addition, Hisun will collaborate with Celsion around the regulatory approval activities for ThermoDox&lt;sup&gt;&amp;#174;&#13;&lt;/sup&gt;with the China State Food and Drug Administration (CHINA FDA). During the first quarter of 2015, Hisun completed the successful&#13;manufacture of three registration batches of ThermoDox&lt;sup&gt;&amp;#174;&lt;/sup&gt;.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;On January 18, 2013, we entered into a technology&#13;development contract with Hisun, pursuant to which Hisun paid us a non-refundable research and development fee of $5 million to support&#13;our development of ThermoDox&lt;sup&gt;&amp;#174;&lt;/sup&gt; in mainland China, Hong Kong and Macau (the China territory). Following our announcement&#13;on January 31, 2013 that the HEAT study failed to meet its primary endpoint, Celsion and Hisun have agreed that the Technology Development&#13;Contract entered into on January 18, 2013 will remain in effect while the parties continue to collaborate and are evaluating the next&#13;steps in relation to ThermoDox&lt;sup&gt;&amp;#174;&lt;/sup&gt;, which include the sub-group analysis of patients in the Phase III HEAT Study for the&#13;hepatocellular carcinoma clinical indication and other activities to further the development of ThermoDox&lt;sup&gt;&amp;#174; &lt;/sup&gt;for the Greater&#13;China market. The $5.0 million received as a non-refundable payment from Hisun in the first quarter 2013 has been recorded to deferred&#13;revenue and will continue to be amortized over the 10 -year term of the agreement, until such time as the parties find a mutually acceptable&#13;path forward on the development of ThermoDox&lt;sup&gt;&amp;#174;&lt;/sup&gt; based on findings of the ongoing post-study analysis of the HEAT Study data.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;On July 19, 2013, the Company and Hisun entered into&#13;a Memorandum of Understanding to pursue ongoing cooperation for the continued clinical development of ThermoDox&lt;sup&gt;&amp;#174;&lt;/sup&gt; as well&#13;as the technology transfer relating to the commercial manufacture of ThermoDox&lt;sup&gt;&amp;#174; &lt;/sup&gt;for the China territory. This expanded&#13;level of cooperation includes development of the next generation liposomal formulation with the goal of creating safer, more efficacious&#13;versions of marketed cancer chemotherapeutics.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Among the key provisions of the Celsion-Hisun Memorandum&#13;of Understanding are:&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="font: 12pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: top"&gt;&#13;    &lt;td style="width: 48px; text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;&amp;#9679;&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;Hisun will provide the Company with internal resources necessary to complete the technology transfer of the Company&amp;#8217;s proprietary manufacturing process and the production of registration batches for the China territory;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: top"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: justify"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: top"&gt;&#13;    &lt;td style="text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;&amp;#9679;&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;Hisun will coordinate with the Company around the clinical and regulatory approval activities for ThermoDox&lt;sup&gt;&amp;#174;&lt;/sup&gt; as well as other liposomal formations with the CHINA FDA; and&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: top"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: justify"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: top"&gt;&#13;    &lt;td style="text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;&amp;#9679;&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: justify"&gt;&lt;font style="font-size: 10pt"&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;&amp;#174;&lt;/sup&gt; for the sale and distribution of ThermoDox&lt;sup&gt;&amp;#174; &lt;/sup&gt;in the China territory.&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;On August 8, 2016, we signed a Technology Transfer,&#13;Manufacturing and Commercial Supply Agreement (&amp;#8220;GEN-1 Agreement&amp;#8221;) with Hisun to pursue an expanded partnership for the technology&#13;transfer relating to the clinical and commercial manufacture and supply of GEN-1, Celsion&amp;#8217;s proprietary gene mediated, IL-12 immunotherapy,&#13;for the greater China territory, with the option to expand into other countries in the rest of the world after all necessary regulatory&#13;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&#13;for potential future studies of GEN-1 in China. GEN-1 is currently being evaluated by Celsion in first line ovarian cancer patients.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Key provisions of the GEN-1 Agreement are as follows:&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0 0 0 9.9pt"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="font: 12pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: top"&gt;&#13;    &lt;td style="width: 48px"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;&amp;#9679;&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;the GEN-1 Agreement has targeted unit costs for clinical supplies of GEN-1 that are substantially competitive with the Company&amp;#8217;s current suppliers;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: top"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: justify"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: top"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;&amp;#9679;&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;once approved, the cost structure for GEN-1 will support rapid market adoption and significant gross margins across global markets;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: top"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: justify"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: top"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;&amp;#9679;&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;Celsion will provide Hisun a certain percentage of China&amp;#8217;s commercial unit demand, and separately of global commercial unit demand, subject to regulatory approval;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: top"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: justify"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: top"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;&amp;#9679;&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: justify"&gt;&lt;font style="font-size: 10pt"&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;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: top"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: justify"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: top"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;&amp;#9679;&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: justify"&gt;&lt;font style="font-size: 10pt"&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;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;The Company evaluated the Hisun arrangement in accordance&#13;with ASC 606 and determined that its performance obligations under the agreement include the non-exclusive, royalty-free license, research&#13;and development services to be provided by the Company, and its obligation to serve on a joint committee. The Company concluded that the&#13;license was not distinct since its value is closely tied to the ongoing research and development activities. As such, the license and&#13;the research and development services are bundled as a single performance obligation. Since the provision of the license and research&#13;and development services are considered a single performance obligation, the $5,000,000 upfront payment is being recognized as revenue&#13;ratably through 2022.&lt;/p&gt;</CLSN:LicensingTransactionTextBlock>
    <CLSN:WarrantsTextBlock contextRef="From2021-01-01to2021-03-31">&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;b&gt;Note 14. Warrants&lt;/b&gt;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Following is a summary of all warrant activity for&#13;the three months ended March 31, 2021:&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="font: 12pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&lt;font style="font-size: 10pt"&gt;Warrants&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Number of&lt;br /&gt;&#13;    Warrants&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Issued&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Weighted&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Average&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Exercise Price&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="width: 58%"&gt;&lt;font style="font-size: 10pt"&gt;Warrants outstanding at December 31, 2020&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 18%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;3,853,566&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 18%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1.35&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Warrants exercised during the three months ended March 31, 2021 (see Note 11)&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;(1,216,667&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;)&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1.24&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Warrants outstanding at March 31, 2021&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;2,636,899&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1.40&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Aggregate intrinsic value of outstanding warrants at March 31, 2021&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;413,500&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Weighted average remaining contractual terms at March 31, 2021&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;4.6 years&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;</CLSN:WarrantsTextBlock>
    <CLSN:EarnoutMilestoneLiabilityDisclosureTextBlock contextRef="From2021-01-01to2021-03-31">&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;b&gt;Note 13. Earn-Out Milestone Liability&lt;/b&gt;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;On March 28, 2019, the Company and EGWU, Inc, entered&#13;into an amendment to its purchase agreement (&amp;#8220;Amended Asset Purchase Agreement&amp;#8221;), whereby payment of the earnout milestone&#13;liability related to the Ovarian Cancer Indication of $12.4 million had been modified. The Company has the option to make the payment&#13;as follows:&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: top"&gt;&#13;    &lt;td style="font: 12pt Times New Roman, Times, Serif; width: 24px; text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;a)&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="font: 12pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;$7.0 million in cash within 10 business days of achieving the milestone; or&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: top"&gt;&#13;    &lt;td style="font: 12pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;b)&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="font: 12pt Times New Roman, Times, Serif; text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;$12.4 million in cash, common stock of the Company, or a combination of either, within one year of achieving the milestone.&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;As of March 31, 2021, and December 31, 2020, the Company&#13;fair valued the earn-out milestone liability at $7.2 million and $7.0 million, respectively, and recognized a non-cash charge of $0.2&#13;million for the three-months ended March 31, 2021. In assessing the earnout milestone liability at March 31, 2021, the Company fair valued&#13;each of the two payment options per the Amended Asset Purchase Agreement and weighted them at 50% and 50% probability for the $7.0 million&#13;and the $12.4 million payments, respectively.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;As of March 31, 2020, and December 31, 2019, the Company&#13;fair valued the earn-out milestone liability at $5.8 million and $5.7 million, respectively and recognized a non-cash charge of $0.1 million&#13;for the three-months ended March 31, 2020. In assessing the earnout milestone liability at March 31, 2020, the Company fair valued each&#13;of the two payment options per the Amended Asset Purchase Agreement and weighted them at 80% and 20% probability for the $7.0 million&#13;and the $12.4 million payments, respectively.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;The following is a summary of the changes in the earn-out&#13;milestone liability for the three-month period ended March 31, 2021:&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="font: 12pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="width: 77%"&gt;&lt;font style="font-size: 10pt"&gt;Balance at January 1, 2021&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 20%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;(7,018,000&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;)&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Non-cash loss from the change in fair value&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;(151,000&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;)&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Balance at March 31, 2021&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;(7,169,000&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;)&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;The following is a schedule of the Company&amp;#8217;s&#13;risk-adjustment assessment of each milestone:&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="font: 12pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;Date&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Risk-adjustment Assessment&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;of Achieving Each Milestone&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;Discount Rate&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Estimated Time&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;to Achieve&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td style="text-align: justify"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="width: 42%; text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;March 31, 2021&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 2%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 13%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;80&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;%&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 2%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 13%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;9&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;%&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 2%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 20%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;0.29 to 1.29 years&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;December 31, 2020&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;80&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;%&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;9&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;%&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;0.54 to 1.54 years&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="text-align: justify"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;March 31, 2020&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;80&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;%&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;9&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;%&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1.04 to 2.04 years&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;December 31, 2019&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;80&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;%&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;9&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;%&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1.12 to 2.12 years&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;</CLSN:EarnoutMilestoneLiabilityDisclosureTextBlock>
    <us-gaap:DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock contextRef="From2021-01-01to2021-03-31">&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;b&gt;Note 12. Stock-Based Compensation&lt;/b&gt;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;The Company has long-term compensation plans that&#13;permit the granting of equity-based awards in the form of stock options, restricted stock, restricted stock units, stock appreciation&#13;rights, other stock awards, and performance awards.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;At the 2018 Annual Stockholders Meeting of the Company&#13;held on May 15, 2018, stockholders approved the Celsion Corporation 2018 Stock Incentive Plan (the &amp;#8220;2018 Plan&amp;#8221;). The 2018&#13;Plan, as adopted, permits the granting of 2,700,000 shares of Celsion common stock as equity awards in the form of incentive stock options,&#13;nonqualified stock options, restricted stock, restricted stock units, stock appreciation rights, other stock awards, performance awards,&#13;or in any combination of the foregoing. At the 2019 Annual Stockholders Meeting of the Company held on May 14, 2019, stockholders approved&#13;an amendment to the 2018 Plan whereby the Company increased the number of common stock shares available by 1,200,000 to a total of 3,900,000&#13;under the 2018 Plan, as amended. Prior to the adoption of the 2018 Plan, the Company had maintained the Celsion Corporation 2007 Stock&#13;Incentive Plan (the &amp;#8220;2007 Plan&amp;#8221;). At the 2020 Annual Stockholders Meeting of the Company held on June 15, 2020, stockholders&#13;approved an amendment to the 2018 Plan, as previously amended, whereby the Company increased the number of shares of common stock available&#13;by 2,500,000 to a total of 6,400,000 under the 2018 Plan, as amended.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;The Company has issued stock awards to employees and&#13;directors in the form of stock options and restricted stock. Options are generally granted with strike prices equal to the fair market&#13;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&#13;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&#13;of any incentive stock option granted to an eligible employee owning more than 10% of the outstanding stock of Celsion must be at least&#13;110% of such fair market value on the date of grant. Only officers and key employees may receive incentive stock options.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Option and restricted stock awards vest upon terms&#13;determined by the Compensation Committee of the Board of Directors and are subject to accelerated vesting in the event of a change of&#13;control or certain terminations of employment. The Company issues new shares to satisfy its obligations from the exercise of options or&#13;the grant of restricted stock awards.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;On September 28, 2018, and again on February 19, 2019,&#13;the Compensation Committee of the Board of Directors approved the grant of (i) inducement stock options (the &amp;#8220;Inducement Option&#13;Grants&amp;#8221;) to purchase a total of 164,004 and 140,004 shares of Celsion common stock, respectively and (ii) inducement restricted&#13;stock awards (the &amp;#8220;Inducement Stock Grants&amp;#8221;) totaling 19,000 and 13,000 shares of Celsion common stock to five new employees&#13;collectively. Each award has a grant date of the date of grant. Each Inducement Option Grant has an exercise price per share equal to&#13;$2.77 and $2.18 which represents the closing price of Celsion&amp;#8217;s common stock as reported by Nasdaq on September 28, 2018 and February&#13;19, 2019, respectively. Each Inducement Option Grant will vest over three years, with one-third vesting on the one-year anniversary of&#13;the employee&amp;#8217;s first day of employment with the Company and one-third vesting on the second and third anniversaries thereafter,&#13;subject to the new employee&amp;#8217;s continued service relationship with the Company on each such date. Each Inducement Option Grant has&#13;a ten-year term and is subject to the terms and conditions of the applicable stock option agreement. Each of Inducement Stock Grant vested&#13;on the one-year anniversary of the employee&amp;#8217;s first day of employment with the Company is subject to the new employee&amp;#8217;s continued&#13;service relationship with the Company through such date and is subject to the terms and conditions of the applicable restricted stock&#13;agreement.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;As of March 31, 2021, there were a total of 6,498,424&#13;shares of Celsion common stock reserved for issuance under the 2018 Plan, which were comprised of 6,420,825 shares of Celsion common stock&#13;subject to equity awards previously granted under the 2018 Plan and 2007 Plan and 77,599 shares of Celsion common stock available for&#13;future issuance under the 2018 Plan. As of December 31, 2020, there were a total of 140,004 shares of Celsion common stock subject to&#13;outstanding inducement awards.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Total compensation cost related to stock options and&#13;restricted stock awards amounted to $1.6 million and $0.5 million for the three-month periods ended March 31, 2021 and 2020, respectively.&#13;Of these amounts, $587,507 and $177,936 was charged to research and development during the three-month periods ended March 31, 2021 and&#13;2020, respectively, and $991,819 and $274,029 was charged to general and administrative expenses during the three-month periods ended&#13;March 31, 2021 and 2020, respectively.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;As of March 31, 2021, there was $4.1 million of total&#13;unrecognized compensation cost related to non-vested stock-based compensation arrangements. That cost is expected to be recognized over&#13;a weighted-average period of 1.3 years. The weighted average grant date fair values of the stock options granted was $2.24 and $1.01 during&#13;the three-month periods ended March 31, 2021 and 2020, respectively. A summary of stock option awards and restricted stock grants for&#13;the three-months ended March 31, 2021 is presented below:&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="font: 12pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="6" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Stock Options&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="6" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Restricted Stock Awards&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Weighted&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Average&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Options&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Outstanding&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Weighted&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Average&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Exercise&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Price&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Non-vested&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Restricted&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Stock&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Outstanding&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Weighted&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Average&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Grant&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Date&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Fair Value&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Contractual&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Terms of&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Equity&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Awards&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;(in years)&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="width: 40%"&gt;&lt;font style="font-size: 10pt"&gt;Equity awards outstanding at January 1, 2021&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 9%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;4,624,725&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 9%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;2.77&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 9%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;2,750&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 9%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;0.89&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 9%; text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Equity awards granted&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;2,032,500&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;2.24&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1,000&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;2.22&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Equity awards exercised or vested and issued&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;(7,500&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;)&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;0.63&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Equity awards forfeited, cancelled or expired&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;(92,646&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;)&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;2.69&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Equity awards outstanding at March 31, 2021&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;6,557,079&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;2.65&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;3,750&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1.31&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;8.0&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Aggregate intrinsic value of outstanding equity awards at March 31, 2021&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;13,163&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;7,875&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Equity awards exercisable at March 31, 2021&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;4,063,706&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;2.70&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;7.8&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Aggregate intrinsic value of equity awards exercisable at March 31, 2021&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;3,300&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;The fair values of stock options granted were estimated&#13;at the date of grant using the Black-Scholes option pricing model. The Black-Scholes model was originally developed for use in estimating&#13;the fair value of traded options, which have different characteristics from Celsion&amp;#8217;s stock options. The model is also sensitive&#13;to changes in assumptions, which can materially affect the fair value estimate. The Company used the following assumptions for determining&#13;the fair value of options granted under the Black-Scholes option pricing model:&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="font: 12pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="6" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Three Months Ended March 31,&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;2021&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;2020&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="width: 58%"&gt;&lt;font style="font-size: 10pt"&gt;Risk-free interest rate&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 18%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1.64 to 1.74&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;%&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 18%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1.33&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;%&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Expected volatility&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;106.8 to 112.5&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;%&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;102.7&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;%&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Expected life (in years)&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;7.5 to 10.0&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;8.5&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Expected dividend yield&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;%&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;%&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Expected volatilities utilized in the model are based&#13;on historical volatility of the Company&amp;#8217;s stock price. The risk-free interest rate is derived from values assigned to U.S. Treasury&#13;bonds with terms that approximate the expected option lives in effect at the time of grant.&lt;/p&gt;</us-gaap:DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock>
    <us-gaap:AccountsPayableAndAccruedLiabilitiesDisclosureTextBlock contextRef="From2021-01-01to2021-03-31">&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;b&gt;Note 9. Accrued Liabilities&lt;/b&gt;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Other accrued liabilities at March 31, 2021 and December&#13;31, 2020 include the following:&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="font: 12pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td style="text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;March 31, 2021&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;December 31, 2020&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td style="text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="width: 62%"&gt;&lt;font style="font-size: 10pt"&gt;Amounts due to contract research organizations and other contractual agreements&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 16%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;855,517&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 16%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;636,000&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Accrued payroll and related benefits&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;790,111&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1,736,271&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Accrued professional fees&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;138,430&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;66,850&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Other&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;19,411&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;19,411&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Total&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1,803,469&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;2,458,532&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;</us-gaap:AccountsPayableAndAccruedLiabilitiesDisclosureTextBlock>
    <us-gaap:IntangibleAssetsDisclosureTextBlock contextRef="From2021-01-01to2021-03-31">&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;b&gt;Note 8. Intangible Assets&lt;/b&gt;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;In June 2014, we completed the acquisition of substantially&#13;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&#13;(&amp;#8220;EGEN&amp;#8221;). We acquired all of EGEN&amp;#8217;s right, title and interest in and to substantially all of the assets of EGEN, including&#13;cash and cash equivalents, patents, trademarks and other intellectual property rights, clinical data, certain contracts, licenses and&#13;permits, equipment, furniture, office equipment, furnishings, supplies and other tangible personal property. In addition, CLSN Laboratories&#13;assumed certain specified liabilities of EGEN, including the liabilities arising out of the acquired contracts and other assets relating&#13;to periods after the closing date.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;i&gt;Acquired In-process Research and Development&lt;/i&gt;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Acquired in-process research and development (IPR&amp;#38;D)&#13;consists of EGEN&amp;#8217;s drug technology platforms: TheraPlas and TheraSilence. The fair value of the IPR&amp;#38;D drug technology platforms&#13;was estimated to be $24.2 million as of the acquisition date. As of the closing of the acquisition, the IPR&amp;#38;D was considered indefinite&#13;lived intangible assets and will not be amortized. IPR&amp;#38;D is reviewed for impairment at least annually as of our third quarter ended&#13;September 30, and whenever events or changes in circumstances indicate that the carrying value of the assets might not be recoverable.&#13;The Company&amp;#8217;s IPR&amp;#38;D consisted of three core elements, its RNA delivery system, its glioblastoma multiforme cancer (GBM) product&#13;candidate and its ovarian cancer indication.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;The Company&amp;#8217;s ovarian cancer indication, with&#13;original value of $13.3 million has not been impaired since its acquisition. At September 30, 2020, the Company evaluated its IPR&amp;#38;D&#13;of the ovarian cancer indication and concluded that it is not more likely than not that the asset is impaired. As no other indicators&#13;of impairment existed during the fourth quarter of 2020 or first quarter of 2021, no impairment charges were recorded during the three&#13;months ended March 31, 2021 and 2020.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;The Company&amp;#8217;s GBM candidate, with original value&#13;of $9.4 million had cumulative impairments through 2018 of $7 million, with remaining carrying value of $2.4 million at December 31, 2019.&#13;On September 30, 2020, the Company evaluated its IPR&amp;#38;D for the (GBM) product candidate and concluded that it is more likely than not&#13;that the asset is further impaired. After this assessment on September 30, 2020, the Company wrote off the remaining $2.4 million of this&#13;asset, thereby recognizing a non-cash charge of $2.4 million in the third quarter of 2020.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;i&gt;Covenants Not to Compete&lt;/i&gt;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Pursuant to the EGEN Purchase Agreement, EGEN provided&#13;certain covenants (&amp;#8220;Covenant Not To Compete&amp;#8221;) to the Company whereby EGEN agreed, during the period ending on the seventh&#13;anniversary of the closing date of the acquisition on June 20, 2014, not to enter into any business, directly or indirectly, which competes&#13;with the business of the Company nor will it contact, solicit or approach any of the employees of the Company for purposes of offering&#13;employment. The Covenant Not to Compete which was valued at approximately $1.6 million at the date of the EGEN acquisition has a definitive&#13;life and is amortized on a straight-line basis over its life of 7 years. The Company recognized amortization expense of $56,829 in each&#13;of the three-month periods ended March 31, 2021 and 2020. The carrying value of the Covenant Not to Compete was $56,831, net of $1,534,383&#13;accumulated amortization as of March 31, 2021 and $113,660, net of $1,477,554 accumulated amortization, as of December 31, 2020.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Following is a schedule of future amortization amounts&#13;during the remaining life of the Covenant Not to Compete.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="font: 12pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Year Ended&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;March 31, 2021&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="width: 79%"&gt;&lt;font style="font-size: 10pt"&gt;2022&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 18%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;56,831&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;2023 and thereafter&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; padding-left: 10pt"&gt;&lt;font style="font-size: 10pt"&gt;Total&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;56,831&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;i&gt;Goodwill&lt;/i&gt;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;The purchase price exceeded the estimated fair value&#13;of the net assets acquired by approximately $2.0 million which was recorded as Goodwill. Goodwill represents the difference between the&#13;total purchase price for the net assets purchased from EGEN and the aggregate fair values of tangible and intangible assets acquired,&#13;less liabilities assumed. Goodwill is reviewed for impairment at least annually as of our third quarter ended September 30 or sooner if&#13;we believe indicators of impairment exist. As of March 31, 2021, we concluded that the Company&amp;#8217;s fair value exceeded its carrying&#13;value therefore &amp;#8220;it is not more likely than not&amp;#8221; that the Goodwill was impaired.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Following is a summary of the net fair value of the&#13;assets acquired in the EGEN asset acquisition for the three-month period ended March 31, 2021:&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="font: 12pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td style="text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;IPR&amp;#38;D&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;Goodwill&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;Covenant Not To Compete&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;For the three-months ended March 31, 2021&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="width: 51%"&gt;&lt;font style="font-size: 10pt"&gt;Balance at January 1, 2021, net&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 13%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;13,366,234&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 13%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1,976,101&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 14%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;113,660&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Amortization&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;(56,829&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;)&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Balance at March 31, 2021, net&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;13,366,234&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1,976,101&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;56,831&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;</us-gaap:IntangibleAssetsDisclosureTextBlock>
    <us-gaap:DerivativesAndFairValueTextBlock contextRef="From2021-01-01to2021-03-31">&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;b&gt;Note 7. Fair Value Measurements&lt;/b&gt;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;FASB ASC Section 820, &lt;i&gt;Fair Value Measurements and&#13;Disclosures&lt;/i&gt; establishes a three-level hierarchy for fair value measurements which requires an entity to maximize the use of observable&#13;inputs and minimize the use of unobservable inputs when measuring fair value. The three levels of inputs that may be used to measure fair&#13;value are as follows:&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0 0 0 0.5in; text-align: justify"&gt;Level 1: Quoted prices (unadjusted) or identical&#13;assets or liabilities in active markets that the entity has the ability to access as of the measurement date;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0 0 0 0.5in; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0 0 0 0.5in; text-align: justify"&gt;Level 2: Significant other observable inputs&#13;other than Level 1 prices such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other&#13;inputs that are observable or can be corroborated by observable market data; and&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0 0 0 0.5in; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0 0 0 0.5in; text-align: justify"&gt;Level 3: Significant unobservable inputs&#13;that reflect a reporting entity&amp;#8217;s own assumptions that market participants would use in pricing an asset or liability.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Cash and cash equivalents, other current assets, accounts&#13;payable and other accrued liabilities are reflected in the condensed consolidated balance sheet at their approximate estimated fair values&#13;primarily due to their short-term nature. The fair values of securities available for sale is determined by relying on the securities&amp;#8217;&#13;relationship to other benchmark quoted securities and classified its investments as Level 2 items in both 2021 and 2020. There were no&#13;transfers of assets or liabilities between Level 1 and Level 2 and no transfers in or out of Level 3 during the three months ended March&#13;31, 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&#13;the earn-out milestone liability included in earnings and in-process R&amp;#38;D. The earnout milestone liability is valued using a risk-adjusted&#13;assessment of the probability of payment of each milestone, discounted to present value using an estimated time to achieve the milestone&#13;(see Note 13).&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Assets and liabilities measured at fair value are&#13;summarized below:&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="font: 12pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td style="text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Total Fair Value&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1)&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Significant Other Observable Inputs&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;(Level 2)&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Significant Unobservable Inputs&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;(Level 3)&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Assets:&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Recurring items as of March 31, 2021&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="width: 46%; padding-left: 10pt"&gt;&lt;font style="font-size: 10pt"&gt;Corporate debt securities, available for sale&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 11%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;15,000,045&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 10%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;&amp;#8211;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 10%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;15,000,045&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 11%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;&amp;#8211;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Non-recurring items as of March 31, 2021&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-left: 10pt"&gt;&lt;font style="font-size: 10pt"&gt;In-process R&amp;#38;D (Note 8)&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;13,366,234&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;&amp;#8211;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;&amp;#8211;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;13,366,234&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Non-recurring items as of December 31, 2020&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="padding-left: 10pt"&gt;&lt;font style="font-size: 10pt"&gt;In-process R&amp;#38;D (Note 8)&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;13,366,234&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;&amp;#8211;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;&amp;#8211;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;13,366,234&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Liabilities:&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Recurring items as of March 31, 2021&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-left: 10pt"&gt;&lt;font style="font-size: 10pt"&gt;Earn-out milestone liability (Note 13)&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;7,169,000&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;&amp;#8211;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;&amp;#8211;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;7,169,000&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Recurring items as of December 31, 2020&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="padding-left: 10pt"&gt;&lt;font style="font-size: 10pt"&gt;Earn-out milestone liability (Note 13)&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;7,018,000&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;&amp;#8211;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;&amp;#8211;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;7,018,000&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;</us-gaap:DerivativesAndFairValueTextBlock>
    <us-gaap:InvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock contextRef="From2021-01-01to2021-03-31">&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;b&gt;Note 6. Investment in Debt Securities Available&#13;for Sale&lt;/b&gt;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Investments in debt securities available for sale&#13;with a fair value of $15,000,045 as of March 31, 2021 consisted of government backed debt securities. These investments are valued at&#13;estimated fair value, with unrealized gains and losses reported as a separate component of stockholders&amp;#8217; equity in accumulated other&#13;comprehensive loss. The Company only had investments in cash and cash equivalents at December 31, 2020.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Investments in debt securities available for sale&#13;are evaluated periodically to determine whether a decline in their value is other than temporary. The term &amp;#8220;other than temporary&amp;#8221;&#13;is not intended to indicate a permanent decline in value. Rather, it means that the prospects for near term recovery of value are not&#13;necessarily favorable, or that there is a lack of evidence to support fair values equal to, or greater than, the carrying value of the&#13;security. Management reviews criteria such as the magnitude and duration of the decline, as well as the reasons for the decline, to predict&#13;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&#13;security is reduced and a corresponding charge to earnings is recognized.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;A summary of the cost, fair value and maturities of&#13;the Company&amp;#8217;s short-term investments is as follows:&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="font: 12pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td style="text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="6" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;March 31, 2021&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="6" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;December 31, 2020&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td style="text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Cost&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Fair Value&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Cost&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Fair Value&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Short-term investments&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="width: 44%; padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Corporate debt securities&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%; padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; width: 11%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;14,998,260&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%; padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%; padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; width: 11%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;15,000,045&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%; padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%; padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; width: 11%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%; padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%; padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; width: 11%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%; padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Total&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;14,998,260&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;15,000,045&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="font: 12pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="6" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;March 31, 2021&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="6" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;December 31, 2020&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td style="text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Cost&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Fair Value&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Cost&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Fair Value&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Short-term investment maturities&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="width: 44%"&gt;&lt;font style="font-size: 10pt"&gt;Within 3 months&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 11%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;8,998,879&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 11%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;8,999,790&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 11%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 11%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Between 3-12 months&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;5,999,381&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;6,000,255&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Total&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;14,998,260&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;15,000,045&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;The following table shows the Company&amp;#8217;s investment&#13;in debt securities available for sale gross unrealized gains (losses) and fair value by investment category and length of time that individual&#13;securities have been in a continuous unrealized loss position at March 31, 2021 and December 31, 2020. The Company has reviewed individual&#13;securities to determine whether a decline in fair value below the amortizable cost basis is other than temporary.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="font: 12pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td style="text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="6" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;March 31, 2021&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="6" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;December 31, 2020&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Available for sale securities (all unrealized holding gains and losses are less than 12 months at date of measurement)&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Fair Value&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Unrealized Holding&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Gains (Losses)&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Fair Value&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Unrealized Holding&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Gains (Losses)&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="width: 44%; padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Investments in debt securities with unrealized gains&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%; padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; width: 11%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;15,000,045&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%; padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%; padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; width: 11%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1,785&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%; padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%; padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; width: 11%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%; padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%; padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; width: 11%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%; padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; padding-left: 10pt"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Total&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;15,000,045&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1,785&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Investment income, which includes net realized losses&#13;on sales of available for sale securities and investment income interest and dividends, is summarized as follows:&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="font: 12pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td style="text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="6" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Three Months Ended &lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;March 31,&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td style="text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;2021&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;2020&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="width: 62%"&gt;&lt;font style="font-size: 10pt"&gt;Interest and dividends accrued and paid&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 16%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;2,411&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 16%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;45,077&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Realized gains&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;&amp;#8211;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;43,232&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Investment income net&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;2,411&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;88,309&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;</us-gaap:InvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock>
    <us-gaap:EarningsPerShareTextBlock contextRef="From2021-01-01to2021-03-31">&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;b&gt;Note 5. Net Loss per Common Share&lt;/b&gt;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Basic loss per share is calculated based upon the&#13;net loss available to common shareholders divided by the weighted average number of common shares outstanding during the period. Diluted&#13;loss per share is calculated after adjusting the denominator of the basic earnings per share computation for the effects of all dilutive&#13;potential common shares outstanding during the period. The dilutive effects of preferred stock, options and warrants and their equivalents&#13;are computed using the treasury stock method.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;The total number of shares of common stock issuable&#13;upon exercise of warrants, stock option grants and equity awards were 9,197,728 and 7,982,990 shares for the three-month periods ended&#13;March 31, 2021 and 2020, respectively. Warrants with an exercise price of $0.01 exercisable for 200,000 shares of common stock were considered&#13;issued in calculating basic loss per share during the first quarter of 2020. These warrants were exercised in October 2020. For the three-month&#13;periods ended March 31, 2021 and 2020, diluted loss per common share was the same as basic loss per common share as the other warrants&#13;and equity awards that were convertible into shares of the Company&amp;#8217;s common stock were excluded from the calculation of diluted&#13;loss per common share as their effect would have been anti-dilutive. The Company did not pay any dividends during the three-month periods&#13;ended March 31, 2021 and 2020.&lt;/p&gt;</us-gaap:EarningsPerShareTextBlock>
    <us-gaap:NewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock contextRef="From2021-01-01to2021-03-31">&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;b&gt;Note 4. New Accounting Pronouncements&lt;/b&gt;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;From time to time, new accounting pronouncements are&#13;issued by the Financial Accounting Standards Board (FASB) and are adopted by us as of the specified effective date. Unless otherwise discussed,&#13;we believe that the impact of recently issued accounting pronouncements will not have a material impact on the Company&amp;#8217;s condensed&#13;consolidated financial position, results of operations, and cash flows, or do not apply to our operations.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;In June 2016, the FASB issued ASU No. 2016-13, &amp;#8220;Financial&#13;Instruments &amp;#8211; Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments&amp;#8221;, which modifies the measurement&#13;of expected credit losses on certain financial instruments. The Company adopted ASU 2016-13 in the first quarter of 2021 utilizing the&#13;modified retrospective transition method. Based on the composition of the Company&amp;#8217;s investment portfolio and current market conditions,&#13;the adoption of ASU 2016-13 did not have a material impact on its consolidated financial statements.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;In December 2019, the FASB issued ASU No. 2019-12,&#13;Income Taxes (Topic 740). The standard simplifies the accounting for incomes taxes by removing certain exceptions to the general principles&#13;in Topic 740 related to the approach for intra-period tax allocation and the recognition of deferred tax liabilities for outside basis&#13;differences. The standard also clarifies the accounting for transactions that result in a step-up in the tax basis of goodwill. The standard&#13;also improves consistent application of and simplifies GAAP for other areas of Topic 740 by clarifying and amending existing guidance.&#13;The amendment is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2020. The Company&#13;adopted this standard during the first quarter of 2021. The adoption of ASU 2019-12 did not have a material impact on its consolidated&#13;financial statements.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;In connection with the upcoming elimination of the&#13;London Inter-bank Offered Rate, (&amp;#8220;LIBOR&amp;#8221;) and other reference interest rates, the FASB issued ASU 2020-04, Reference Rate&#13;Reform (Topic 848) Facilitation of the Effects of Reference Reform on Financial Reporting. ASU 2020-04, which is available for contract&#13;modifications and hedging relationship modifications entered into or evaluated before December 31, 2022, provides certain practical expedients&#13;related to simplifying the accounting for contract modifications resulting from the change in terms from LIBOR to a new required interest&#13;rate benchmark. The Company is currently evaluating the effects of adopting this accounting standards update.&lt;/p&gt;</us-gaap:NewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock>
    <us-gaap:BusinessDescriptionAndAccountingPoliciesTextBlock contextRef="From2021-01-01to2021-03-31">&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;b&gt;Note 1. Business Description&lt;/b&gt;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Celsion Corporation (&amp;#8220;Celsion&amp;#8221; and the&#13;&amp;#8220;Company&amp;#8221;) is a fully integrated, clinical stage biotechnology company focused on advancing a portfolio of innovative treatments&#13;including DNA-based immunotherapies, next generation vaccines and directed chemotherapies through clinical trials and eventual commercialization.&#13;The Company&amp;#8217;s product pipeline includes GEN-1, a DNA-based immunotherapy for the localized treatment of ovarian cancer and ThermoDox&lt;sup&gt;&amp;#174;&lt;/sup&gt;,&#13;a proprietary heat-activated liposomal encapsulation of doxorubicin, currently under investigator-sponsored development for several cancer&#13;indications. Celsion has two feasibility stage platform technologies for the development of novel nucleic acid-based immunotherapies and&#13;next generation vaccines and other anti-cancer DNA or RNA therapies. Both are novel synthetic, non-viral vectors with demonstrated capability&#13;in nucleic acid cellular transfection.&lt;/p&gt;</us-gaap:BusinessDescriptionAndAccountingPoliciesTextBlock>
    <us-gaap:AvailableForSaleSecuritiesTextBlock contextRef="From2021-01-01to2021-03-31">&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;A summary of the cost, fair value and maturities of&#13;the Company&amp;#8217;s short-term investments is as follows:&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="font: 12pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td style="text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="6" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;March 31, 2021&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="6" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;December 31, 2020&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td style="text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Cost&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Fair Value&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Cost&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Fair Value&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Short-term investments&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="width: 44%; padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Corporate debt securities&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%; padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; width: 11%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;14,998,260&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%; padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%; padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; width: 11%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;15,000,045&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%; padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%; padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; width: 11%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%; padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%; padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; width: 11%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%; padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Total&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;14,998,260&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;15,000,045&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="font: 12pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="6" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;March 31, 2021&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="6" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;December 31, 2020&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td style="text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Cost&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Fair Value&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Cost&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Fair Value&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Short-term investment maturities&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="width: 44%"&gt;&lt;font style="font-size: 10pt"&gt;Within 3 months&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 11%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;8,998,879&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 11%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;8,999,790&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 11%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 11%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Between 3-12 months&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;5,999,381&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;6,000,255&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;Total&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;14,998,260&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;15,000,045&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;</us-gaap:AvailableForSaleSecuritiesTextBlock>
    <CLSN:ScheduleOfChangesInEarnOutMilestoneLiabilitiesTableTextBlock contextRef="From2021-01-01to2021-03-31">&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;The following is a summary of the changes in the earn-out&#13;milestone liability for the three-month period ended March 31, 2021:&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="font: 12pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="width: 77%"&gt;&lt;font style="font-size: 10pt"&gt;Balance at January 1, 2021&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 20%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;(7,018,000&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;)&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Non-cash loss from the change in fair value&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;(151,000&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;)&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Balance at March 31, 2021&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;(7,169,000&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;)&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;</CLSN:ScheduleOfChangesInEarnOutMilestoneLiabilitiesTableTextBlock>
    <CLSN:ScheduleOfRiskadjustmentAssessmentTableTextBlock contextRef="From2021-01-01to2021-03-31">&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;The following is a schedule of the Company&amp;#8217;s&#13;risk-adjustment assessment of each milestone:&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="font: 12pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;Date&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Risk-adjustment Assessment&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;of Achieving Each Milestone&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;Discount Rate&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;Estimated Time&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;to Achieve&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td style="text-align: justify"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="text-align: center"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="width: 42%; text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;March 31, 2021&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 2%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 13%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;80&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;%&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 2%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 13%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;9&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;%&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 2%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 20%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;0.29 to 1.29 years&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;December 31, 2020&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;80&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;%&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;9&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;%&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;0.54 to 1.54 years&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="text-align: justify"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;March 31, 2020&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;80&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;%&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;9&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;%&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1.04 to 2.04 years&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;December 31, 2019&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;80&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;%&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;9&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;%&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1.12 to 2.12 years&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;</CLSN:ScheduleOfRiskadjustmentAssessmentTableTextBlock>
    <us-gaap:PaymentsToAcquireAvailableForSaleSecuritiesDebt contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">14998260</us-gaap:PaymentsToAcquireAvailableForSaleSecuritiesDebt>
    <us-gaap:PaymentsToAcquireAvailableForSaleSecuritiesDebt contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">9940534</us-gaap:PaymentsToAcquireAvailableForSaleSecuritiesDebt>
    <us-gaap:ProceedsFromStockOptionsExercised contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">4725</us-gaap:ProceedsFromStockOptionsExercised>
    <us-gaap:ProceedsFromStockOptionsExercised contextRef="From2020-01-01to2020-03-31" unitRef="USD" xsi:nil="true" />
    <us-gaap:StockIssued1 contextRef="From2021-01-01to2021-03-31" unitRef="USD" xsi:nil="true" />
    <us-gaap:StockIssued1 contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">498632</us-gaap:StockIssued1>
    <us-gaap:IncreaseDecreaseInAccountsPayableAndAccruedLiabilities contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">-898581</us-gaap:IncreaseDecreaseInAccountsPayableAndAccruedLiabilities>
    <us-gaap:IncreaseDecreaseInAccountsPayableAndAccruedLiabilities contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">-504952</us-gaap:IncreaseDecreaseInAccountsPayableAndAccruedLiabilities>
    <CLSN:IncreaseDecreaseInReceivableOnSaleOfNetOperatingLosses contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">1845823</CLSN:IncreaseDecreaseInReceivableOnSaleOfNetOperatingLosses>
    <CLSN:IncreaseDecreaseInReceivableOnSaleOfNetOperatingLosses contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">1819324</CLSN:IncreaseDecreaseInReceivableOnSaleOfNetOperatingLosses>
    <us-gaap:ContractWithCustomerLiabilityRevenueRecognized contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">125000</us-gaap:ContractWithCustomerLiabilityRevenueRecognized>
    <us-gaap:ContractWithCustomerLiabilityRevenueRecognized contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">125000</us-gaap:ContractWithCustomerLiabilityRevenueRecognized>
    <us-gaap:StockIssuedDuringPeriodValueStockOptionsExercised contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">4725</us-gaap:StockIssuedDuringPeriodValueStockOptionsExercised>
    <us-gaap:StockIssuedDuringPeriodValueStockOptionsExercised contextRef="From2021-01-01to2021-03-31_us-gaap_CommonStockMember" unitRef="USD" decimals="0">75</us-gaap:StockIssuedDuringPeriodValueStockOptionsExercised>
    <us-gaap:StockIssuedDuringPeriodValueStockOptionsExercised contextRef="From2021-01-01to2021-03-31_us-gaap_AdditionalPaidInCapitalMember" unitRef="USD" decimals="0">4650</us-gaap:StockIssuedDuringPeriodValueStockOptionsExercised>
    <us-gaap:StockIssuedDuringPeriodValueStockOptionsExercised contextRef="From2021-01-01to2021-03-31_us-gaap_AccumulatedOtherComprehensiveIncomeMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:StockIssuedDuringPeriodValueStockOptionsExercised contextRef="From2021-01-01to2021-03-31_us-gaap_RetainedEarningsMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:StockIssuedDuringPeriodValueStockOptionsExercised contextRef="From2021-01-01to2021-03-31_us-gaap_TreasuryStockMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:StockIssuedDuringPeriodValueNewIssues contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">38943478</us-gaap:StockIssuedDuringPeriodValueNewIssues>
    <us-gaap:StockIssuedDuringPeriodValueNewIssues contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">5794747</us-gaap:StockIssuedDuringPeriodValueNewIssues>
    <us-gaap:StockIssuedDuringPeriodValueNewIssues contextRef="From2020-01-01to2020-03-31_us-gaap_CommonStockMember" unitRef="USD" decimals="0">55713</us-gaap:StockIssuedDuringPeriodValueNewIssues>
    <us-gaap:StockIssuedDuringPeriodValueNewIssues contextRef="From2021-01-01to2021-03-31_us-gaap_CommonStockMember" unitRef="USD" decimals="0">330941</us-gaap:StockIssuedDuringPeriodValueNewIssues>
    <us-gaap:StockIssuedDuringPeriodValueNewIssues contextRef="From2020-01-01to2020-03-31_us-gaap_AdditionalPaidInCapitalMember" unitRef="USD" decimals="0">5739034</us-gaap:StockIssuedDuringPeriodValueNewIssues>
    <us-gaap:StockIssuedDuringPeriodValueNewIssues contextRef="From2021-01-01to2021-03-31_us-gaap_AdditionalPaidInCapitalMember" unitRef="USD" decimals="0">38612537</us-gaap:StockIssuedDuringPeriodValueNewIssues>
    <us-gaap:StockIssuedDuringPeriodValueNewIssues contextRef="From2020-01-01to2020-03-31_us-gaap_AccumulatedOtherComprehensiveIncomeMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:StockIssuedDuringPeriodValueNewIssues contextRef="From2021-01-01to2021-03-31_us-gaap_AccumulatedOtherComprehensiveIncomeMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:StockIssuedDuringPeriodValueNewIssues contextRef="From2020-01-01to2020-03-31_us-gaap_RetainedEarningsMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:StockIssuedDuringPeriodValueNewIssues contextRef="From2021-01-01to2021-03-31_us-gaap_RetainedEarningsMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:StockIssuedDuringPeriodValueNewIssues contextRef="From2020-01-01to2020-03-31_us-gaap_TreasuryStockMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:StockIssuedDuringPeriodValueNewIssues contextRef="From2021-01-01to2021-03-31_us-gaap_TreasuryStockMember" unitRef="USD" xsi:nil="true" />
    <us-gaap:BasisOfAccounting contextRef="From2021-01-01to2021-03-31">&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;b&gt;Note 2. Basis of Presentation&lt;/b&gt;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;The accompanying unaudited condensed consolidated&#13;financial statements, which include the accounts of the Company and its wholly owned subsidiary, CLSN Laboratories, Inc, have been prepared&#13;in accordance with generally accepted accounting principles in the United States (GAAP) for interim financial information and with the&#13;instructions to Form 10-Q and Article 10 of Regulation S-X. All significant intercompany balances and transactions have been eliminated&#13;in consolidation. Certain information and disclosures normally included in financial statements prepared in accordance with GAAP have&#13;been condensed or omitted pursuant to such rules and regulations.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;In the opinion of management, all adjustments, consisting&#13;only of normal recurring accruals considered necessary for a fair presentation, have been included in the accompanying unaudited condensed&#13;consolidated financial statements. Operating results for the three-month period March 31, 2021 and 2020 are not necessarily indicative&#13;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&#13;statements and notes thereto included in the Company&amp;#8217;s Annual Report on Form 10-K for the fiscal year ended December 31, 2020 filed&#13;with the Securities and Exchange Commission (SEC) on March 19, 2021.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;The preparation of financial statements in conformity&#13;with GAAP requires management to make judgments, estimates, and assumptions that affect the amount reported in the Company&amp;#8217;s financial&#13;statements and accompanying notes. Actual results could differ materially from those estimates. Events and conditions arising subsequent&#13;to the most recent balance sheet date have been evaluated for their possible impact on the financial statements and accompanying notes.&#13;The Company continues to monitor the impact of the COVID-19 pandemic on its financial condition and results of operations, along with&#13;the valuation of its long-term assets, intangible assets, and goodwill. The effect of this matter could potentially have an impact on&#13;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;/p&gt;</us-gaap:BasisOfAccounting>
    <us-gaap:CommitmentsAndContingenciesDisclosureTextBlock contextRef="From2021-01-01to2021-03-31">&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;b&gt;Note 17. Commitments and Contingencies&lt;/b&gt;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;On September 20, 2019, a purported stockholder of&#13;the Company filed a derivative and putative class action lawsuit against the Company and certain officers and directors (the &amp;#8220;Shareholder&#13;Action&amp;#8221;). The Company was a defendant in this derivative and putative class action lawsuit in the Superior Court of New Jersey,&#13;Chancery Division, filed by a shareholder against the Company (as both a class action defendant and nominal defendant), and certain of&#13;its officers and directors (the &amp;#8220;Individual Defendants&amp;#8221;), with the caption &lt;i&gt;O&amp;#8217;Connor v. Braun et al., Docket No. MER-C-000068-19&lt;/i&gt;&#13;(the &amp;#8220;Shareholder Action&amp;#8221;). The Shareholder Action alleged breaches of the defendants&amp;#8217; fiduciary duties based on allegations&#13;that the defendants omitted or made improper statements when seeking shareholder approval of the 2018 Stock Incentive Plan. The Shareholder&#13;Action sought, among other things, any damages sustained by the Company as a result of the defendants&amp;#8217; alleged wrongdoing, a declaratory&#13;judgment against all defendants invalidating the 2018 Stock Incentive Plan and declaring any awards made under the Plan invalid, rescinded,&#13;and subject to disgorgement, an order disgorging the equity awards granted to the Individual Defendants under the 2018 Stock Incentive&#13;Plan, and attorneys&amp;#8217; fees and costs.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;On April 24, 2020, the Company, the Individual Defendants,&#13;and the plaintiff (the &amp;#8220;Parties&amp;#8221;) entered into a Settlement Agreement and Release (the &amp;#8220;Settlement Agreement&amp;#8221;),&#13;which memorializes the terms of the Parties&amp;#8217; settlement of the Shareholder Action (the &amp;#8220;Settlement&amp;#8221;). The Settlement&#13;calls for repricing of certain stock options and payment of plaintiff legal fees of $187,500. On July 24, 2020, the Court issued an order&#13;approving the Parties&amp;#8217; proposed form of notice to shareholders regarding the Settlement. A hearing was held on September 8, 2020&#13;whereby the Court issued a final approval approving the Settlement. Pursuant to the Settlement, the Company paid $187,500 on October 1,&#13;2020. Without admitting the validity of any of the claims asserted in the Shareholder Action, or any liability with respect thereto, and&#13;expressly denying all allegations of wrongdoing, fault, liability, or damage against the Company and the Individual Defendants arising&#13;out of any of the conduct, statements, acts or omissions alleged, or that could have been alleged, in the Shareholder Action, the Company&#13;and the Individual Defendants concluded that it was desirable that the claims be settled on the terms and subject to the conditions set&#13;forth in the Settlement Agreement. The Company and the Individual Defendants entered into the Settlement Agreement for settlement purposes&#13;only and solely to avoid the cost and disruption of further litigation.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;On October 29, 2020, a putative securities class action&#13;was filed against the Company and certain of its officers and directors (the &amp;#8220;Spar Individual Defendants&amp;#8221;) in the U.S. District&#13;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&#13;that the Company and Individual Defendants made false and misleading statements regarding one of the Company&amp;#8217;s product candidates,&#13;ThermoDox&lt;sup&gt;&amp;#174;&lt;/sup&gt;, and brings claims for damages under Section 10(b) of the Exchange Act and Rule 10b-5 promulgated thereunder&#13;against all Defendants, and under Section 20(a) of the Exchange Act of 1934 against the Spar Individual Defendants. The Company believes&#13;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,&#13;if any, will be realized, nor an estimate of possible loss or range of loss, if any, can be determined.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;In February 2021, a derivative shareholder lawsuit&#13;was filed against the Company, as the nominal defendant, and certain of its directors and officers as defendants in the U.S. District&#13;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&#13;breach of fiduciary duty and other claims arising out of alleged statements made by certain of the Company&amp;#8217;s directors and/or officers&#13;regarding ThermoDox&lt;sup&gt;&amp;#174;.&lt;/sup&gt; The Company believes it has meritorious defenses to these claims and intends to vigorously contest&#13;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&#13;loss or range of loss, if any, can be determined.&lt;/p&gt;</us-gaap:CommitmentsAndContingenciesDisclosureTextBlock>
    <CLSN:CashAndCashEquivalentsShorttermInvestmentsAndReceivableOnSaleOfNetOperatingLosses contextRef="AsOf2021-03-31" unitRef="USD" decimals="0">54600000</CLSN:CashAndCashEquivalentsShorttermInvestmentsAndReceivableOnSaleOfNetOperatingLosses>
    <CLSN:NoncashCharge contextRef="From2020-07-01to2020-09-30_custom_EGENIncMember_custom_GlioblastomaMultiformeBrainCancerMember" unitRef="USD" decimals="0">2400000</CLSN:NoncashCharge>
    <us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths contextRef="AsOf2021-03-31_us-gaap_NoncompeteAgreementsMember" unitRef="USD" decimals="0">56831</us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths>
    <CLSN:FiniteLivedIntangibleAssetsAmortizationExpenseYearTwoAndAfter contextRef="AsOf2021-03-31_us-gaap_NoncompeteAgreementsMember" unitRef="USD" xsi:nil="true" />
    <CLSN:GainLossFromChangeInEarnoutMilestoneLiability contextRef="From2021-01-01to2021-03-31" unitRef="USD" decimals="0">-151000</CLSN:GainLossFromChangeInEarnoutMilestoneLiability>
    <CLSN:GainLossFromChangeInEarnoutMilestoneLiability contextRef="From2020-01-01to2020-03-31" unitRef="USD" decimals="0">-41274</CLSN:GainLossFromChangeInEarnoutMilestoneLiability>
    <us-gaap:SubstantialDoubtAboutGoingConcernTextBlock contextRef="From2021-01-01to2021-03-31">&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;b&gt;Note 3. Financial Condition and Business Plan&lt;/b&gt;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Since inception, the Company has incurred substantial&#13;operating losses, principally from expenses associated with the Company&amp;#8217;s research and development programs, clinical trials conducted&#13;in connection with the Company&amp;#8217;s product candidates, and applications and submissions to the U.S. Food and Drug Administration.&#13;The Company has not generated significant revenue and has incurred significant net losses in each year since our inception. As of March&#13;31, 2021, the Company has incurred approximately $318 million of cumulative net losses and had approximately $54.6 million in cash and&#13;cash equivalents, short-term investments and receivable on sale of net operating losses. We have substantial future capital requirements&#13;to continue our research and development activities and advance our product candidates through various development stages. The Company&#13;believes these expenditures are essential for the commercialization of its technologies.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;The Company expects its operating losses to continue&#13;for the foreseeable future as it continues its product development efforts, and when it undertakes marketing and sales activities. The&#13;Company&amp;#8217;s ability to achieve profitability is dependent upon its ability to obtain governmental approvals, manufacture, and market&#13;and sell its product candidates. There can be no assurance that the Company will be able to commercialize its technology successfully&#13;or that profitability will ever be achieved. The operating results of the Company have fluctuated significantly in the past.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;In January 2020, the WHO declared an outbreak of coronavirus,&#13;COVID-19, to be a &amp;#8220;Public Health Emergency of International Concern,&amp;#8221; and the U.S. Department of Health and Human Services&#13;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,&#13;including the U.S. Governments and businesses around the world have taken unprecedented actions to mitigate the spread of COVID-19, including,&#13;but not limited to, shelter-in-place orders, quarantines, significant restrictions on travel, as well as restrictions that prohibit many&#13;employees from going to work. Uncertainty with respect to the economic impacts of the pandemic has introduced significant volatility in&#13;the financial markets. The Company did not observe significant impacts on its business or results of operations during 2020 and into 2021&#13;due to COVID-19. While the extent to which COVID-19 impacts the Company&amp;#8217;s future results will depend on future developments, the&#13;pandemic and associated economic impacts could result in a material impact to the Company&amp;#8217;s future financial condition, results&#13;of operations and cash flows. The Company&amp;#8217;s ability to raise additional capital may be adversely impacted by potential worsening&#13;global economic conditions and the recent disruptions to, and volatility in, financial markets in the U.S. and worldwide resulting from&#13;the ongoing COVID-19 pandemic. The disruptions caused by COVID-19 may also disrupt the clinical trials process and enrolment of patients.&#13;This may delay commercialization efforts. The Company continues to monitor its operating activities in light of these events. The specific&#13;impact, if any, is not readily determinable as of the date of these financial statements.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;The actual amount of funds the Company will need to&#13;operate is subject to many factors, some of which are beyond the Company&amp;#8217;s control. These factors include the following:&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="font: 12pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: top"&gt;&#13;    &lt;td style="width: 48px; text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;&amp;#9679;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;the progress of research activities;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: top"&gt;&#13;    &lt;td style="text-align: justify"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: justify"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: top"&gt;&#13;    &lt;td style="text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;&amp;#9679;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;the number and scope of research programs;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: top"&gt;&#13;    &lt;td style="text-align: justify"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: justify"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: top"&gt;&#13;    &lt;td style="text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;&amp;#9679;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;the progress of preclinical and clinical development activities;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: top"&gt;&#13;    &lt;td style="text-align: justify"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: justify"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: top"&gt;&#13;    &lt;td style="text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;&amp;#9679;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;the progress of the development efforts of parties with whom the Company has entered into research and development agreements;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: top"&gt;&#13;    &lt;td style="text-align: justify"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: justify"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: top"&gt;&#13;    &lt;td style="text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;&amp;#9679;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;the costs associated with additional clinical trials of product candidates;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: top"&gt;&#13;    &lt;td style="text-align: justify"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: justify"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: top"&gt;&#13;    &lt;td style="text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;&amp;#9679;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;the ability to maintain current research and development licensing arrangements and to establish new research and development and licensing arrangements;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: top"&gt;&#13;    &lt;td style="text-align: justify"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: justify"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: top"&gt;&#13;    &lt;td style="text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;&amp;#9679;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;the ability to achieve milestones under licensing arrangements;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: top"&gt;&#13;    &lt;td style="text-align: justify"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: justify"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: top"&gt;&#13;    &lt;td style="text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;&amp;#9679;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;the costs involved in prosecuting and enforcing patent claims and other intellectual property rights; and&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: top"&gt;&#13;    &lt;td style="text-align: justify"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: justify"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: top"&gt;&#13;    &lt;td style="text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;&amp;#9679;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="text-align: justify"&gt;&lt;font style="font-size: 10pt"&gt;the costs and timing of regulatory approvals.&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;On July 13, 2020, the Company announced that it has&#13;received a recommendation from the independent DMC to consider stopping the global Phase III OPTIMA Study of ThermoDox&lt;sup&gt;&amp;#174; &lt;/sup&gt;in&#13;combination with RFA for the treatment of HCC, or primary liver cancer. The recommendation was made following the second pre-planned interim&#13;safety and efficacy analysis by the DMC on July 9, 2020. The DMC&amp;#8217;s analysis found that the pre-specified boundary for stopping the&#13;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&#13;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.&#13;On February 11, 2021, the Company issued a letter to shareholders stating that the Company was notifying all clinical sites to discontinue&#13;following patients in the OPTIMA Study.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;During 2020, 2019 and 2018, the Company submitted&#13;applications to sell a portion of the Company&amp;#8217;s State of New Jersey net operating losses as part of the Technology Business Tax&#13;Certificate Program sponsored by The New Jersey Economic Development Authority. Under the program, emerging biotechnology companies with&#13;unused NOLs and unused research and development credits are allowed to sell these benefits to other New Jersey-based companies. In 2018&#13;and 2019, the Company sold NOLs totaling $13 million receiving net proceeds of $12.2 million. In June 2020 and as updated in September&#13;2020, the Company filed an application with the New Jersey Economic Development Authority to sell substantially all of its remaining State&#13;of New Jersey net operating losses totaling $2.0 million available under the program. On February 12, 2021, the New Jersey Economic Development&#13;Authority approved the full amount of the Company&amp;#8217;s application. In February of 2021, the Company entered into an agreement to sell&#13;the net operating losses from the 2020 application and the Company received net proceeds of approximately $1.85 million on May 10, 2021.&#13;During 2021, the New Jersey State Legislature increased the maximum lifetime benefit per company from $15 million to $20 million, which&#13;will allow the Company to participate in this innovative funding program in future years.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;In June 2018, the Company entered into a Credit Agreement&#13;with Horizon Technology Finance Corporation (&amp;#8220;Horizon&amp;#8221;) that provided $10 million in capital (the &amp;#8220;Horizon Credit Agreement&amp;#8221;).&#13;The obligations under the Horizon Credit Agreement are secured by a first-priority security interest in substantially all assets of Celsion&#13;other than intellectual property assets. Payments under the loan agreement are interest only (calculated based on one-month LIBOR plus&#13;7.625%) for the first 24 months through July 2020, followed by a 21-month amortization period of principal and interest starting on August&#13;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&#13;Credit Agreement, Celsion repaid $5 million of the $10 million loan and $0.2 million in related end of term charges, and the remaining&#13;$5 million in obligations were restructured as more fully discussed in Note 10 to these financial statements.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;As more fully discussed in Note 11, during 2021 through&#13;the date of the filing of this Quarterly Report on Form 10-Q, the Company has raised approximately $6.9 million in gross proceeds from&#13;the use of its JonesTrading Capital on Demand&lt;sup&gt;TM&lt;/sup&gt; financing facility, $35 million from a registered direct financing completed&#13;in January 2021, $15 million from a registered direct financing completed on April 5, 2021, and $1.5 million from warrant exercises. With&#13;$54.6 million in cash and cash equivalents, short-term investments and income tax receivable from the sale of its New Jersey net operating&#13;loss at March 31, 2021, coupled with $15 million of gross proceeds received from the sale of equity from a registered direct offering&#13;it completed on April 5, 2021, the Company believes it has sufficient capital resources to fund its operations through the end of 2024.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;The Company has based its estimates on assumptions&#13;that may prove to be wrong. The Company may need to obtain additional funds sooner or in greater amounts than it currently anticipates.&#13;Potential sources of financing include strategic relationships, public or private sales of the Company&amp;#8217;s shares or debt, the sale&#13;of the Company&amp;#8217;s State of New Jersey net operating losses and other sources. If the Company raises funds by selling additional shares&#13;of common stock or other securities convertible into common stock, the ownership interest of existing stockholders may be diluted.&lt;/p&gt;</us-gaap:SubstantialDoubtAboutGoingConcernTextBlock>
    <us-gaap:DebtDisclosureTextBlock contextRef="From2021-01-01to2021-03-31">&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;b&gt;Note 10. Note Payable&lt;/b&gt;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;i&gt;Horizon Credit Agreement&lt;/i&gt;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;On June 27, 2018, the Company entered into a loan&#13;agreement with Horizon Technology Finance Corporation (&amp;#8220;Horizon&amp;#8221;) that provided $10 million in new capital (the &amp;#8220;Horizon&#13;Credit Agreement&amp;#8221;). The Company drew down $10 million upon closing of the Horizon Credit Agreement on June 27, 2018. On August 28,&#13;2020, Horizon and the Company amended the Horizon Credit Agreement (the &amp;#8220;Amendment&amp;#8221;) whereby Celsion repaid $5 million of&#13;the $10 million loan and $0.2 million in related end of term charges, and the remaining $5 million in obligations were restructured as&#13;set forth below.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Pursuant to the Amendment, the remaining $5 million&#13;in obligations of Celsion under the Horizon Credit Agreement are secured by a first-priority security interest in substantially all assets&#13;of Celsion other than intellectual property assets. The obligations bear interest at a rate calculated based an amount by which the one-month&#13;LIBOR exceeds 2% plus 7.625%. In no event shall the interest rate be less than 9.625%. Payments pursuant to the Amendment are interest&#13;only for the first twelve (12) months after August 1, 2020, followed by a 21-month amortization period of principal and interest through&#13;the scheduled maturity date on April 1, 2023. In addition, the remaining $5 million in obligations is subject to an end of term fee equal,&#13;in the aggregate, to $275,000, which amount shall be payable upon the maturity of the obligations or upon the date of final payment or&#13;default, as applicable. In connection with the Amendment, Celsion agreed to a liquidity covenant which provides that, at all times, Celsion&#13;shall maintain unrestricted cash and/or cash equivalents on deposit in accounts over which the applicable Lenders maintain an account&#13;control agreement in an amount not less than $2.5 million. In addition, pursuant to the Amendment, Celsion agreed to provide evidence&#13;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,&#13;debt, its New Jersey net operating losses, or a combination thereof, subsequent to the date of the Amendment. The Company met this requirement&#13;during the fourth quarter of 2020.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;In connection with the Horizon Credit Agreement, the&#13;Company incurred financing fees and expenses totaling $175,000 which were recorded and classified as debt discount. In addition, the Company&#13;paid loan origination fees of $100,000 which were recorded and classified as debt discount. These debt discount amounts totaling $782,116&#13;were being amortized as interest expense using the effective interest method over the life of the loan. Also, in connection with each&#13;of the Horizon Credit Agreement, the Company is required to pay an end of term charge equal to 4.0% of the original loan amount at time&#13;of maturity. Therefore, these amounts totaling $400,000 were being amortized as interest expense using the effective interest method over&#13;the life of the loan.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;As a fee in connection with the Horizon Credit Agreement,&#13;Celsion issued Horizon warrants exercisable for a total of 190,114 shares of Celsion&amp;#8217;s common stock (the &amp;#8220;Existing Warrants&amp;#8221;)&#13;at a per share exercise price of $2.63. The Horizon Warrants were immediately exercisable for cash or by net exercise from the date of&#13;grant and will expire after ten years from the date of grant. The Company valued the Horizon Warrants issued using the Black-Scholes option&#13;pricing model and recorded a total of $507,116 as a direct deduction from the debt liability, consistent with the presentation of debt&#13;discounts, and are being amortized as interest expense using the effective interest method over the life of the loan. Pursuant to the&#13;Amendment, one-half of the aggregate Existing Warrants, exercisable for a total of 95,057 shares of Celsion&amp;#8217;s common stock, have&#13;been canceled, and, in connection with the Amendment, Celsion issued Horizon new warrants exercisable at a per share exercise price equal&#13;to $1.01 for a total of 247,525 shares of Celsion&amp;#8217;s common stock (the &amp;#8220;New Warrants&amp;#8221; and, together with the Existing&#13;Warrants, the &amp;#8220;Warrants&amp;#8221;). The remaining 95,057 Existing Warrants issued in connection with the Horizon Credit Agreement remain&#13;outstanding at a per share exercise price of $2.63.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;The New Warrants are immediately exercisable for cash&#13;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&#13;Credit Agreement contains customary representations, warranties and affirmative and negative covenants including, among other things,&#13;covenants that limit or restrict Celsion&amp;#8217;s ability to grant liens, incur indebtedness, make certain restricted payments, merge,&#13;or consolidate and make dispositions of assets.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;The Amendment was evaluated in accordance with FASB&#13;ASC 470-50, &lt;i&gt;Debt-Modifications and Extinguishments&lt;/i&gt;, for debt modification and extinguishment accounting. We accounted for the $5&#13;million we repaid as a debt extinguishment thereby reducing the principal obligations accordingly. Also, in connection with the $5 million&#13;repayment, we recognized as interest expense, approximately $0.2 million of unamortized debt discount, deferred financing and end of term&#13;fees related to the repaid obligation in August 2020.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;We accounted for the remaining $5 million of obligation&#13;under the Amendment as a debt modification to the initial agreement with respect to the minor changes in cash flows. Also, in connection&#13;with the $5 million remaining obligations, we recorded $5,000 of financing fees and the New Warrant fair value of $247,548 as additional&#13;debt discount on the $5 million remaining obligation. Therefore, approximately $109,706 of unamortized debt discount will be amortized&#13;over the remaining life of the new obligations. The $275,000 of end of term fees, net of previously amortized end of term fees totaling&#13;$142,605 previously accrued on the original note associated with the $5 million remaining obligation, will be amortized as interest expense&#13;over the remaining life of the new obligations.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;During the three-month period ended March 31, 2021,&#13;the Company incurred $120,313 in interest expense and amortized $37,301 as interest expense for debt discounts and end of term charges&#13;in connection with the Horizon Credit Agreement. During the three-month period ended March 31, 2020, the Company incurred $243,299 in&#13;interest expense and amortized $96,066 as interest expense for debt discounts and end of term charges in connection with the Horizon Credit&#13;Agreement.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Following is a schedule of future principal payments,&#13;net of unamortized debt discounts and amortized end of term charges, due on the Horizon Credit Agreement, as amended:&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="font: 12pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;As of March 31,&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="width: 77%"&gt;&lt;font style="font-size: 10pt"&gt;2022&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 20%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1,904,760&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;2023&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;2,857,140&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;2024 and thereafter&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;238,100&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Subtotal of future principal payments&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;5,000,000&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Unamortized debt premium, net&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;88,461&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; padding-left: 10pt"&gt;&lt;font style="font-size: 10pt"&gt;Total&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;5,088,461&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;</us-gaap:DebtDisclosureTextBlock>
    <us-gaap:ScheduleOfMaturitiesOfLongTermDebtTableTextBlock contextRef="From2021-01-01to2021-03-31">&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Following is a schedule of future principal payments,&#13;net of unamortized debt discounts and amortized end of term charges, due on the Horizon Credit Agreement, as amended:&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="font: 12pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid; text-align: center"&gt;&lt;font style="font-size: 10pt"&gt;&lt;b&gt;As of March 31,&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="width: 77%"&gt;&lt;font style="font-size: 10pt"&gt;2022&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 20%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1,904,760&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;2023&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;2,857,140&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;2024 and thereafter&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;238,100&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Subtotal of future principal payments&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;5,000,000&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Unamortized debt premium, net&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;88,461&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="padding-bottom: 2.5pt; padding-left: 10pt"&gt;&lt;font style="font-size: 10pt"&gt;Total&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;5,088,461&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;</us-gaap:ScheduleOfMaturitiesOfLongTermDebtTableTextBlock>
    <us-gaap:StockholdersEquityNoteDisclosureTextBlock contextRef="From2021-01-01to2021-03-31">&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;b&gt;Note 11. Stockholders&amp;#8217; Equity&lt;/b&gt;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;In September 2018, the Company filed with the SEC&#13;a $75 million shelf registration statement on Form S-3 (the 2018 Shelf Registration Statement) that allows the Company to issue any combination&#13;of common stock, preferred stock or warrants to purchase common stock or preferred stock. This shelf registration was declared effective&#13;on October 12, 2018 and during January 2021, had been fully utilized by the end of January 2021.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;On March 19, 2021, the Company filed with the SEC&#13;a $100 million shelf registration statement on Form S-3 (the &amp;#8220;2021 Registration Statement&amp;#8221;) that allows the Company to issue&#13;any combination of common stock, preferred stock or warrants to purchase common stock or preferred stock. This shelf registration was&#13;declared effective on March 30, 2021.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;i&gt;&lt;u&gt;Capital on Demand&lt;sup&gt;TM&lt;/sup&gt; Sales Agreement&lt;/u&gt;&lt;/i&gt;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;On December 4, 2018, the Company entered into the&#13;Capital on Demand Agreement with JonesTrading, pursuant to which the Company may offer and sell, from time to time, through JonesTrading&#13;shares of Common Stock having an aggregate offering price of up to $16.0 million.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;During 2020, the Company sold and issued an aggregate&#13;of 5.2 million shares under the Capital on Demand Agreement, receiving approximately $6.2 million in gross proceeds none of which were&#13;sold during the first quarter of 2020. During the first quarter of 2021, the Company sold 7.2 million shares under the Capital on Demand&#13;Agreement, receiving approximately $6.9 million in gross proceeds under the Capital on Demand Agreement.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;i&gt;&lt;u&gt;Registered Direct Offering&lt;/u&gt;&lt;/i&gt;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;On February 27, 2020, we entered into a Securities&#13;Purchase Agreement (the &amp;#8220;February 2020 Purchase Agreement&amp;#8221;) with several institutional investors, pursuant to which we agreed&#13;to issue and sell, in a registered direct offering (the &amp;#8220;February 2020 Offering&amp;#8221;), an aggregate of 4,571,428 shares of our&#13;common stock at an offering price of $1.05 per Share for gross proceeds of approximately $4.8 million before the deduction of the Placement&#13;Agent fees and offering expenses. In a concurrent private placement (the &amp;#8220;Private Placement&amp;#8221;), the Company issued to the investors&#13;that participated in the February 2020 Offering, for no additional consideration, warrants to purchase up to 2,971,428 shares of common&#13;stock (the &amp;#8220;Original Warrants&amp;#8221;). The Original Warrants were initially exercisable six months following their date of issue&#13;and were set to expire on the five-year anniversary of such initial exercise date. The Original Warrants had an exercise price of $1.15&#13;per share subject to adjustment as provided therein. On March 12, 2020, the Company entered into private exchange agreements (the &amp;#8220;Exchange&#13;Agreements&amp;#8221;) with holders of the Original Warrants. Pursuant to the Exchange Agreements, in return for a higher exercise price of&#13;$1.24 per share of common stock, the Company issued new warrants to the Investors to purchase up to 3,200,000 shares of common stock (the&#13;&amp;#8220;Exchange Warrants&amp;#8221;) in exchange for the Original Warrants. The Exchange Warrants, like the Original Warrants, are initially&#13;exercisable six months following their issuance (the &amp;#8220;Initial Exercise Date&amp;#8221;) and expire on the five-year anniversary of their&#13;Initial Exercise Date. Other than having a higher exercise price, different issue date, Initial Exercise Date and expiration date, the&#13;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&#13;Statement to register the shares of common stock issuable under the Exchange Warrants; the Registration Statement was declared effective&#13;by the SEC on August 13, 2020. No Exchange Warrants were exercised during 2020. During 2021 through the date of this Quarterly Report&#13;on Form 10-Q, the Company issued 1.2 million shares pursuant to investors exercising Exchange Warrants, receiving approximately $1.5 million.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;b&gt;&amp;#160;&lt;/b&gt;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;i&gt;&lt;u&gt;Underwritten Offering&lt;/u&gt;&lt;/i&gt;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;On June 22, 2020, the Company entered into an underwriting&#13;agreement (the &amp;#8220;Underwriting Agreement&amp;#8221;) with Oppenheimer &amp;#38; Co. Inc. (the &amp;#8220;Underwriter&amp;#8221;), relating to the&#13;issuance and sale (the &amp;#8220;Underwritten Offering&amp;#8221;) of 2,666,667 shares of the Company&amp;#8217;s common stock. Pursuant to the terms&#13;of the Underwriting Agreement, the Underwriter agreed to purchase the shares at a price of $3.4875 per share. The Underwriter offered&#13;the shares at a public offering price of $3.75 per share, reflecting an underwriting discount equal to $0.2625, or 7.0% of the public&#13;offering price. The net proceeds to the Company from the Underwritten Offering, after deducting the underwriting discount and estimated&#13;offering expenses payable by the Company, were approximately $9.1 million.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Pursuant to the Underwriting Agreement, until December&#13;31, 2020, the Underwriter had a right of first refusal to act as sole underwriter, initial purchaser, placement/selling agent, or arranger,&#13;as the case may be, on any new financing for the Company (excluding equipment lease financings, loans or grants from governmental authorities&#13;or in connection with government programs and financings relating to or sales of tax attributes) during such period. The Underwriter common&#13;stock the sole right to determine whether or not any other broker dealer shall have the right to participate in any such offering and&#13;the economic terms of any such participation.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;i&gt;&lt;u&gt;January 2021 Registered Direct Offering&lt;/u&gt;&lt;/i&gt;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;On January 22, 2021, the Company entered into a Securities&#13;Purchase Agreement (the &amp;#8220;January 2021 Purchase Agreement&amp;#8221;) with several institutional investors, pursuant to which the Company&#13;agreed to issue and sell, in a registered direct offering (the &amp;#8220;January 2021 Offering&amp;#8221;), an aggregate of 25,925,925 shares&#13;of the Company&amp;#8217;s common stock at an offering price of $1.35 per share for gross proceeds of approximately $35 million before the&#13;deduction of the January 2021 Placement Agents (as defined below) fee and offering expenses. The January 2021 Purchase Agreement contains&#13;customary representations, warranties and agreements by the Company and customary conditions to closing. The closing of the January 2021&#13;Offering occurred on January 26, 2021.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;In connection with the January 2021 Offering, the&#13;Company entered into a placement agent agreement (the &amp;#8220;January 2021 Placement Agent Agreement&amp;#8221;) with A.G.P./Alliance Global&#13;Partners (together with Brookline Capital Markets, the &amp;#8220;January 2021 Placement Agents&amp;#8221;) pursuant to which the Company agreed&#13;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&#13;sold in the January 2021 Offering and reimburse the January 2021 Placement Agents for certain of their expenses in an amount not to exceed&#13;$82,500.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;i&gt;&lt;u&gt;March 2021 Registered Direct Offering&lt;/u&gt;&lt;/i&gt;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;On March 31, 2021, the Company entered into a Securities&#13;Purchase Agreement (the &amp;#8220;March 2021 Purchase Agreement&amp;#8221;) with several institutional investors, pursuant to which the Company&#13;agreed to issue and sell, in a registered direct offering (the &amp;#8220;March 2021 Offering&amp;#8221;), an aggregate of 11,538,462 shares of&#13;the Company&amp;#8217;s common stock, at an offering price of $1.30 per share for gross proceeds of approximately $15 million before the deduction&#13;of the placement agents fee and offering expenses. The shares were offered by the Company pursuant to the 2021 Registration Statement.&#13;The closing of the Offering occurred on April 5, 2021. The Company will account for the March 2021 Offering in the second quarter of 2021.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;In connection with the March 2021 Offering, the Company&#13;entered into a placement agent agreement (the &amp;#8220;March 2021 Placement Agent Agreement&amp;#8221;) with A.G.P./Alliance Global Partners,&#13;as lead placement agent (&amp;#8220;AGP,&amp;#8221; and together with JonesTrading Institutional Services LLC and Brookline Capital Markets, a&#13;division of Arcadia Securities, LLC, serving as co-placement agents, the &amp;#8220;March 2021 Placement Agents&amp;#8221;) pursuant to which&#13;the Company agreed to pay the March 2021 Placement Agents an aggregate cash fee equal to 7% of the aggregate gross proceeds raised from&#13;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&#13;$82,500.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Under the March 2021 Purchase Agreement and March&#13;2021 Placement Agent Agreement, the Company and its subsidiaries are prohibited, for a period of 90 days after the closing, from entering&#13;into any agreement to issue or announcing any issuance or proposed issuance of common stock or any other securities that are at any time&#13;convertible into, or exercisable or exchangeable for, or otherwise entitle the holder thereof to receive common stock without the prior&#13;written consent of AGP or the investors participating in the offering. For purposes of this offering, AGP and the investors from the Company&amp;#8217;s&#13;January 2021 Offering waived a similar 90-day restriction in the placement agent agreement and purchase agreement for that transaction.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;i&gt;&lt;u&gt;LPC Purchase Agreement&lt;/u&gt;&lt;/i&gt;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;On September 8, 2020, the Company entered into a purchase&#13;agreement (the &amp;#8220;LPC Purchase Agreement&amp;#8221;) and a Registration Rights Agreement (the &amp;#8220;Registration Rights Agreement&amp;#8221;)&#13;with Lincoln Park Capital Fund, LLC (&amp;#8220;Lincoln Park&amp;#8221;), pursuant to which, upon the terms and subject to the conditions and&#13;limitations set forth therein, the Company has the right to sell to Lincoln Park up to $26.0 million of shares of the Company&amp;#8217;s&#13;common stock at the Company&amp;#8217;s discretion as described below (the &amp;#8220;LPC Offering&amp;#8221;). During 2020, the Company sold and&#13;issued an aggregate of 3.3 million shares, including the 437,828 commitment shares, under the LPC Purchase Agreement, receiving approximately&#13;$2.2 million in gross proceeds. The Company sent a letter to Lincoln Park terminating the LPC Offering effective January 21, 2021. The&#13;Company did not sell any shares under the LPC Purchase Agreement in 2021.&lt;/p&gt;</us-gaap:StockholdersEquityNoteDisclosureTextBlock>
    <us-gaap:LesseeOperatingLeasesTextBlock contextRef="From2021-01-01to2021-03-31">&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;b&gt;Note 15. Leases&lt;/b&gt;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;In 2011, the Company executed a lease (the &amp;#8220;Lease&amp;#8221;)&#13;with Brandywine Operating Partnership, L.P. (Brandywine), a Delaware limited partnership, for a 10,870 square foot premises located in&#13;Lawrenceville, New Jersey and relocated its offices to Lawrenceville, New Jersey from Columbia, Maryland. The Lease had an initial term&#13;of 66 months. In late 2015, Lenox Drive Office Park LLC purchased the real estate and office building and assumed the Lease. This Lease&#13;was set to expire on April 30, 2017. In April 2017, the Company and the landlord amended the Lease effective May 1, 2017. The 1&lt;sup&gt;st&lt;/sup&gt;&#13;Lease Amendment extended the term of the agreement for an additional 64 months, reduced the premises to 7,565 square feet, reduced the&#13;monthly rent and provided four months free rent. The monthly rent ranged from approximately $18,900 in the first year to approximately&#13;$20,500 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&#13;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&#13;term by one year to September 1, 2023. The monthly rent ranges from approximately $25,035 in the first year to approximately $27,088 in&#13;the final year of the 2&lt;sup&gt;nd&lt;/sup&gt; Lease Amendment.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;In connection with the EGEN Asset Purchase Agreement&#13;in June 2014, the Company assumed the existing lease with another landlord for an 11,500 square foot premises located in Huntsville Alabama.&#13;In January 2018, the Company and the Huntsville landlord entered into a new 60-month lease which reduced the premises to 9,049 square&#13;feet with rent payments of approximately $18,100 per month.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;We adopted ASC Topic 842 on January 1, 2019 using&#13;the modified retrospective transition method for all lease arrangements at the beginning of the period of adoption. Results for reporting&#13;periods beginning January 1, 2019 are presented under ASC 842, while prior period amounts were not adjusted and continue to be reported&#13;in accordance with our historic accounting under Topic 840, Leases. The standard had a material impact on our Condensed Consolidated Balance&#13;Sheet but had no impact on our condensed consolidated net earnings and cash flows. The most significant impact of adopting ASC Topic 842&#13;was the recognition of the right-of-use (ROU) asset and lease liabilities for operating leases, which are presented in the following three-line&#13;items on the Consolidated Condensed Balance Sheet: (i) operating lease right-of-use asset; (ii) current operating lease liabilities; and&#13;(iii) operating lease liabilities. Therefore, on date of adoption of ASC Topic 842, the Company recognized a ROU asset of $1.4 million,&#13;operating lease liabilities, current and non-current collectively, of $1.5 million and reduced other liabilities by approximately $0.1&#13;million. We elected the package of practical expedients for leases that commenced before the effective date of ASC Topic 842 whereby we&#13;elected to not reassess the following: (i) whether any expired or existing contracts contain leases; (ii) the lease classification for&#13;any expired or existing leases; and (iii) initial direct costs for any existing leases. In addition, we have lease agreements with lease&#13;and non-lease components, and we have elected the practical expedient for all underlying asset classes and account for them as a single&#13;lease component. We have no finance leases. We determine if an arrangement is a lease at inception. We have operating leases for office&#13;space and research and development facilities. Neither of our leases include options to renew, however, one contains an option for early&#13;termination. We considered the option of early termination in measurement of right-of-use assets and lease liabilities and we determined&#13;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&#13;January 2019, the Company considered this as one modified lease and not as two separate leases. Therefore, in January 2019, the Company&#13;determined this lease was an operating lease and remeasured the ROU asset and lease liability. Therefore, the Company increased the ROU&#13;asset and operating lease liabilities by $0.4 million to $1.8 million and $1.9 million, respectively.&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Following is a table of the lease payments and maturity&#13;of our operating lease liabilities as of March 31, 2021:&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="font: 12pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;For the&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;year ending&lt;br /&gt;&#13;    March 31,&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="width: 77%"&gt;&lt;font style="font-size: 10pt"&gt;Remainder of 2021&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 20%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;398,872&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="background-color: white"&gt;&#13;    &lt;td style="vertical-align: top"&gt;&lt;font style="font-size: 10pt"&gt;2022&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="vertical-align: bottom"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="vertical-align: bottom"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="vertical-align: bottom; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;535,579&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="vertical-align: bottom"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="background-color: #CCEEFF"&gt;&#13;    &lt;td style="vertical-align: top"&gt;&lt;font style="font-size: 10pt"&gt;2023&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="vertical-align: bottom"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="vertical-align: bottom"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="vertical-align: bottom; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;233,116&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="vertical-align: bottom"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;2024 and thereafter&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Subtotal future lease payments&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1,167,567&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; padding-left: 10pt"&gt;&lt;font style="font-size: 10pt"&gt;Less imputed interest&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;(127,384&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;)&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Total lease liabilities&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1,040,183&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Weighted average remaining life&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;2.2 years&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Weighted average discount rate&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;9.98&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;%&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;For the three-month period ending March 31, 2021,&#13;operating lease expense was $130,595 and cash paid for operating leases included in operating cash flows was $131,863. For the three-month&#13;period ending March 31, 2020, operating lease expense was $130,595 and cash paid for operating leases included in operating cash flows&#13;was $130,631.&lt;/p&gt;</us-gaap:LesseeOperatingLeasesTextBlock>
    <us-gaap:LesseeOperatingLeaseLiabilityMaturityTableTextBlock contextRef="From2021-01-01to2021-03-31">&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Following is a table of the lease payments and maturity&#13;of our operating lease liabilities as of March 31, 2021:&lt;/p&gt;&#13;&#13;&lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;&#13;&#13;&lt;table cellspacing="0" cellpadding="0" style="font: 12pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse"&gt;&#13;  &lt;tr style="vertical-align: bottom"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td colspan="2" style="border-bottom: black 1.5pt solid"&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;For the&lt;/b&gt;&lt;/p&gt;&#13;    &lt;p style="font: 10pt Times New Roman, Times, Serif; margin: 0; text-align: center"&gt;&lt;b&gt;year ending&lt;br /&gt;&#13;    March 31,&lt;/b&gt;&lt;/p&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="width: 77%"&gt;&lt;font style="font-size: 10pt"&gt;Remainder of 2021&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 20%; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;398,872&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="width: 1%"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="background-color: white"&gt;&#13;    &lt;td style="vertical-align: top"&gt;&lt;font style="font-size: 10pt"&gt;2022&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="vertical-align: bottom"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="vertical-align: bottom"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="vertical-align: bottom; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;535,579&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="vertical-align: bottom"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="background-color: #CCEEFF"&gt;&#13;    &lt;td style="vertical-align: top"&gt;&lt;font style="font-size: 10pt"&gt;2023&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="vertical-align: bottom"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="vertical-align: bottom"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="vertical-align: bottom; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;233,116&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="vertical-align: bottom"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;2024 and thereafter&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;-&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td&gt;&lt;font style="font-size: 10pt"&gt;Subtotal future lease payments&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1,167,567&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt; padding-left: 10pt"&gt;&lt;font style="font-size: 10pt"&gt;Less imputed interest&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;(127,384&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;)&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Total lease liabilities&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&lt;font style="font-size: 10pt"&gt;$&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;1,040,183&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Weighted average remaining life&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 1.5pt solid; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;2.2 years&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 1.5pt"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: white"&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="text-align: right"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;Weighted average discount rate&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double"&gt;&amp;#160;&lt;/td&gt;&#13;    &lt;td style="border-bottom: black 2.25pt double; text-align: right"&gt;&lt;font style="font-size: 10pt"&gt;9.98&lt;/font&gt;&lt;/td&gt;&#13;    &lt;td style="padding-bottom: 2.5pt"&gt;&lt;font style="font-size: 10pt"&gt;%&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&#13;  &lt;/table&gt;</us-gaap:LesseeOperatingLeaseLiabilityMaturityTableTextBlock>
</xbrli:xbrl>
