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  <xs:element id="kros_ShareBasedCompensationArrangementByShareBasedPaymentAwardAnnualIncreasePercentOfSharesOutstanding" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAnnualIncreasePercentOfSharesOutstanding" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="kros_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValueAbstract" abstract="true" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValueAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="kros_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseExecutiveCompensationAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationNondeductibleExpenseExecutiveCompensationAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="kros_EffectiveIncomeTaxRateReconciliationForeignWithholdingTaxesPercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationForeignWithholdingTaxesPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="kros_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseExecutiveCompensationPercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationNondeductibleExpenseExecutiveCompensationPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="kros_DeferredTaxAssetsDeferredExpenseCapitalizedResearchAndDevelopmentCost" abstract="false" name="DeferredTaxAssetsDeferredExpenseCapitalizedResearchAndDevelopmentCost" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="kros_DeferredTaxAssetsOperatingLeaseLiability" abstract="false" name="DeferredTaxAssetsOperatingLeaseLiability" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="kros_DeferredTaxLiabilitiesOperatingLeaseRightOfUseAsset" abstract="false" name="DeferredTaxLiabilitiesOperatingLeaseRightOfUseAsset" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="kros_OperatingLossCarryforwardWriteOff" abstract="false" name="OperatingLossCarryforwardWriteOff" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="kros_PhaseAPremisesMember" abstract="true" name="PhaseAPremisesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kros_WalthamLeaseMember" abstract="true" name="WalthamLeaseMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kros_AccentTherapeuticsIncMember" abstract="true" name="AccentTherapeuticsIncMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kros_LesseeAreaOfSublease" abstract="false" name="LesseeAreaOfSublease" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:areaItemType"/>
  <xs:element id="kros_LesseeOperatingLeaseMonthlyBaseRent" abstract="false" name="LesseeOperatingLeaseMonthlyBaseRent" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="kros_LesseeOperatingLeasePeriodForImprovement" abstract="false" name="LesseeOperatingLeasePeriodForImprovement" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="kros_LesseeOperatingLeaseAnnualIncreaseInMonthlyBasePaymentPercentage" abstract="false" name="LesseeOperatingLeaseAnnualIncreaseInMonthlyBasePaymentPercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="kros_LesseeOperatingLeaseMonthlyBaseRentPerSquareFoot" abstract="false" name="LesseeOperatingLeaseMonthlyBaseRentPerSquareFoot" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:areaItemType"/>
  <xs:element id="kros_LesseeOperatingLeaseAreaOfRentalSpace" abstract="false" name="LesseeOperatingLeaseAreaOfRentalSpace" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:areaItemType"/>
  <xs:element id="kros_LesseeLeaseOtherInformationAbstract" abstract="true" name="LesseeLeaseOtherInformationAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="kros_LesseeOperatingLeaseLiabilityToBePaidYearSix" abstract="false" name="LesseeOperatingLeaseLiabilityToBePaidYearSix" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="kros_TakedaPharmaceuticalsU.S.A.Inc.Member" abstract="true" name="TakedaPharmaceuticalsU.S.A.Inc.Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kros_LicensesAgreementPlannedStockholderDistributionFromProceedsPercentage" abstract="false" name="LicensesAgreementPlannedStockholderDistributionFromProceedsPercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="kros_HansohAgreementMember" abstract="true" name="HansohAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kros_TechTransferAgreementMember" abstract="true" name="TechTransferAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kros_SupplyAgreementMember" abstract="true" name="SupplyAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kros_HansohShanghaiHealthtechCoLtdMember" abstract="true" name="HansohShanghaiHealthtechCoLtdMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kros_ManufacturingTechnologyTransferAgreementMember" abstract="true" name="ManufacturingTechnologyTransferAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kros_ClinicalProductSupplyAgreementMember" abstract="true" name="ClinicalProductSupplyAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kros_LicenseAndKnowHowMember" abstract="true" name="LicenseAndKnowHowMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kros_TransitionServicesMember" abstract="true" name="TransitionServicesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kros_RevenueRemainingPerformanceObligationDevelopmentMilestonesVariableConsideration" abstract="false" name="RevenueRemainingPerformanceObligationDevelopmentMilestonesVariableConsideration" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="kros_RevenueRemainingPerformanceObligationSalesMilestonesVariableConsideration" abstract="false" name="RevenueRemainingPerformanceObligationSalesMilestonesVariableConsideration" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="kros_RevenueFromContractWithCustomerWithholdingTaxes" abstract="false" name="RevenueFromContractWithCustomerWithholdingTaxes" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="kros_ServiceAndOtherRevenue" abstract="false" name="ServiceAndOtherRevenue" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="kros_LicenseAgreementUpfrontFee" abstract="false" name="LicenseAgreementUpfrontFee" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="kros_PotentialMilestonePaymentsDevelopmentBasedMilestones" abstract="false" name="PotentialMilestonePaymentsDevelopmentBasedMilestones" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="kros_PotentialMilestonePaymentsCommercialBasedMilestones" abstract="false" name="PotentialMilestonePaymentsCommercialBasedMilestones" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="kros_PotentialMilestonePaymentsSalesBasedMilestones" abstract="false" name="PotentialMilestonePaymentsSalesBasedMilestones" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="kros_NumberOfPerformanceObligations" abstract="false" name="NumberOfPerformanceObligations" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="kros_LicenseRevenueMember" abstract="true" name="LicenseRevenueMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kros_ReportableSegmentMember" abstract="true" name="ReportableSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kros_RinvaterceptProgramExpensesMember" abstract="true" name="RinvaterceptProgramExpensesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kros_ElriterceptProgramExpensesMember" abstract="true" name="ElriterceptProgramExpensesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kros_CiboterceptProgramExpensesMember" abstract="true" name="CiboterceptProgramExpensesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kros_PreclinicalDevelopmentExpensesMember" abstract="true" name="PreclinicalDevelopmentExpensesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kros_OtherExternalCostsMember" abstract="true" name="OtherExternalCostsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kros_A2025RestructuringMember" abstract="true" name="A2025RestructuringMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kros_RestructuringIncurredCostStatementOfIncomeOrComprehensiveIncomeExtensibleEnumerationNotDisclosedFlag" abstract="false" name="RestructuringIncurredCostStatementOfIncomeOrComprehensiveIncomeExtensibleEnumerationNotDisclosedFlag" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="kros_KeithRegnanteMember" abstract="true" name="KeithRegnanteMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kros_LorenaLernerMember" abstract="true" name="LorenaLernerMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kros_NimaFarzanMember" abstract="true" name="NimaFarzanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kros_JuliusKnowlesMember" abstract="true" name="JuliusKnowlesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kros_AlpnaSethMember" abstract="true" name="AlpnaSethMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="kros_JeanJacquesBienaimeMember" abstract="true" name="JeanJacquesBienaimeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
