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  <xs:element id="flks_UniversityOfUtahResearchFoundationMember" abstract="true" name="UniversityOfUtahResearchFoundationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="flks_StockIssuedDuringPeriodForInProcessResearchAndDevelopmentTechnologyValueNewIssues" abstract="false" name="StockIssuedDuringPeriodForInProcessResearchAndDevelopmentTechnologyValueNewIssues" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="flks_RevenueFromGrantsRevenueSharingPaymentsContinuedPaymentsPercentOfNetSales" abstract="false" name="RevenueFromGrantsRevenueSharingPaymentsContinuedPaymentsPercentOfNetSales" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
</xs:schema>
