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<!-- Creation Date :2022-11-08T21:07:09.2142+00:00 -->
<!-- Copyright (c) 2022 Donnelly Financial Solutions, Inc. All Rights Reserved. -->
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  <xsd:element id="clsd_OperatingLeasesRentExpenseMinimumRentalsPerMonth" name="OperatingLeasesRentExpenseMinimumRentalsPerMonth" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
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  <xsd:element id="clsd_PrepaymentFeePercentageOfOriginalPrincipalAmountOfTermLoans" name="PrepaymentFeePercentageOfOriginalPrincipalAmountOfTermLoans" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="clsd_ProceedsFromIssuanceAtTheMarket" name="ProceedsFromIssuanceAtTheMarket" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
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  <xsd:element id="clsd_SecondMilestoneProceedsFromRoyaltyPurchaseAndSaleAgreement" name="SecondMilestoneProceedsFromRoyaltyPurchaseAndSaleAgreement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
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  <xsd:element id="clsd_TwoThousandSixteenEmployeeStockPurchasePlanMember" name="TwoThousandSixteenEmployeeStockPurchasePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
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  <xsd:element id="clsd_LiabilityRelatedToSalesOfFutureRoyaltiesAndNonCashInterestExpensePolicyTextBlock" name="LiabilityRelatedToSalesOfFutureRoyaltiesAndNonCashInterestExpensePolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="clsd_LicenseAndOtherAgreementsDisclosureTextBlock" name="LicenseAndOtherAgreementsDisclosureTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="clsd_RoyaltyPurchaseAndSaleAgreementTextBlock" name="RoyaltyPurchaseAndSaleAgreementTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="clsd_ScheduleOfActivityOfPurchaseAndSaleAgreementTableTextBlock" name="ScheduleOfActivityOfPurchaseAndSaleAgreementTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="clsd_StockPurchaseWarrantsDisclosureTextBlock" name="StockPurchaseWarrantsDisclosureTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
</xsd:schema>
