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  <xs:element id="flks_PreFundedWarrantAndAccompanyingCommonStockWarrantsMember" abstract="true" name="PreFundedWarrantAndAccompanyingCommonStockWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="flks_ClassOfWarrantOrRightPurchasePricePerWarrantOrRight" abstract="false" name="ClassOfWarrantOrRightPurchasePricePerWarrantOrRight" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="flks_CommonStockPercentageIssued" abstract="false" name="CommonStockPercentageIssued" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="flks_HCWainwrightCoLLCWarrantsMember" abstract="true" name="HCWainwrightCoLLCWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="flks_WarrantsAndRightsExercisableTerm" abstract="false" name="WarrantsAndRightsExercisableTerm" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="flks_ClassOfWarrantOrRightExercisesInPeriod" abstract="false" name="ClassOfWarrantOrRightExercisesInPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="flks_EquityIncentivePlan2015Member" abstract="true" name="EquityIncentivePlan2015Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="flks_EffectiveIncomeTaxRateReconciliationTrueUpsPercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationTrueUpsPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="flks_ReportableSegmentMember" abstract="true" name="ReportableSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="flks_SP3164Member" abstract="true" name="SP3164Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="flks_SP2577Member" abstract="true" name="SP2577Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="flks_FacilityCostAndOther" abstract="false" name="FacilityCostAndOther" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="flks_MergerAgreementMember" abstract="true" name="MergerAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="flks_DecoyTherapeuticsInc.Member" abstract="true" name="DecoyTherapeuticsInc.Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="flks_SalariusLegacyStockholdersMember" abstract="true" name="SalariusLegacyStockholdersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="flks_DecoyStockholdersMember" abstract="true" name="DecoyStockholdersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="flks_ATMAgreementMember" abstract="true" name="ATMAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="flks_SaleOfStockPercentageOfTotalSharesOutstanding" abstract="false" name="SaleOfStockPercentageOfTotalSharesOutstanding" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="flks_BusinessCombinationEquityInterestsIssuableBaseValue" abstract="false" name="BusinessCombinationEquityInterestsIssuableBaseValue" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="flks_QualifiedFinancingCovenantProceedsFromFutureOfferings" abstract="false" name="QualifiedFinancingCovenantProceedsFromFutureOfferings" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="flks_ClassOfWarrantOrRightNumberOfSecuritiesCancelledInExchangeForCash" abstract="false" name="ClassOfWarrantOrRightNumberOfSecuritiesCancelledInExchangeForCash" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
