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  <xsd:element id="kymr_SeriesAConvertiblePreferredStockMember" name="SeriesAConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="kymr_DeferredRevenueVertexMember" name="DeferredRevenueVertexMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="kymr_PriorNoticePeriod" name="PriorNoticePeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="kymr_IncomeTaxDisclosureTable" name="IncomeTaxDisclosureTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="kymr_LesseeOperatingAndFinanceLeasesTextBlock" name="LesseeOperatingAndFinanceLeasesTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="kymr_MilestoneReceivable" name="MilestoneReceivable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="kymr_IssuanceOfCommonStockAndAccompanyingPreFundedWarrantsAtPrivatePlacementNetOfIssuanceCosts" name="IssuanceOfCommonStockAndAccompanyingPreFundedWarrantsAtPrivatePlacementNetOfIssuanceCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="kymr_AccumulatedAmortization" name="AccumulatedAmortization" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="kymr_UnbilledReceivablesSanofiMember" name="UnbilledReceivablesSanofiMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="kymr_ProceedsFromConcurrentPrivatePlacementFollowOn" name="ProceedsFromConcurrentPrivatePlacementFollowOn" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="kymr_DeferredRevenueSanofiMember" name="DeferredRevenueSanofiMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="kymr_FairValue" name="FairValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="kymr_LabAndOfficeEquipmentMember" name="LabAndOfficeEquipmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="kymr_PropertyPlantAndEquipmentNotInService" name="PropertyPlantAndEquipmentNotInService" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="kymr_FairValueAssetsLevel2ToLevel3TransfersAmount" name="FairValueAssetsLevel2ToLevel3TransfersAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="kymr_ChangesInWarrantLiabilityMeasureAtFairValueTableTextBlock" name="ChangesInWarrantLiabilityMeasureAtFairValueTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="kymr_CollaborationAgreementTransactionPrice" name="CollaborationAgreementTransactionPrice" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="kymr_CambridgeMassachusettsMember" name="CambridgeMassachusettsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="kymr_WrittenNoticePeriodToTerminateCollaborationAgreement" name="WrittenNoticePeriodToTerminateCollaborationAgreement" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="kymr_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour" name="LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="kymr_IssuanceOfClassifiedWarrants" name="IssuanceOfClassifiedWarrants" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="kymr_TenantImprovementAllowance" name="TenantImprovementAllowance" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="kymr_OperatingLeasePaymentsProceeds" name="OperatingLeasePaymentsProceeds" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="kymr_DebtSecuritiesAvailableForSaleDeclineInMarketValueForUnrealizedLossPositionNumberOfSecurities" name="DebtSecuritiesAvailableForSaleDeclineInMarketValueForUnrealizedLossPositionNumberOfSecurities" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="kymr_SeriesB1ConvertiblePreferredStockMember" name="SeriesB1ConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="kymr_BaseRentAnnualIncreaseOverTheLeaseTerm" name="BaseRentAnnualIncreaseOverTheLeaseTerm" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="kymr_ProceedsFromFollowOnOfferingNetOfUnderwritingDiscountsAndOfferingCosts" name="ProceedsFromFollowOnOfferingNetOfUnderwritingDiscountsAndOfferingCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="kymr_TemporaryEquityStockSharesVestingOfSeriesAPreferredStockInConnectionWithCollaborationArrangement" name="TemporaryEquityStockSharesVestingOfSeriesAPreferredStockInConnectionWithCollaborationArrangement" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="kymr_TwoThousandNineteenLeaseMember" name="TwoThousandNineteenLeaseMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="kymr_SeriesSeedConvertiblePreferredStockMember" name="SeriesSeedConvertiblePreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="kymr_SignificantAccountingPoliciesTable" name="SignificantAccountingPoliciesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="kymr_LeaseAdditionalTerm" name="LeaseAdditionalTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="kymr_MinimumPreFundedWarrantsExercise" name="MinimumPreFundedWarrantsExercise" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="kymr_LesseeOperatingAndFinancingLeaseLiabilityMaturityTableTextBlock" name="LesseeOperatingAndFinancingLeaseLiabilityMaturityTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="kymr_ScenarioPotentialOutcomeAxis" name="ScenarioPotentialOutcomeAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="kymr_CostReimbursementPaymentReceived" name="CostReimbursementPaymentReceived" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="kymr_SummaryOfWeightedAverageRemainingLeaseTermsAndDiscountRatesTableTextBlock" name="SummaryOfWeightedAverageRemainingLeaseTermsAndDiscountRatesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="kymr_PropertyAndEquipmentImprovements" name="PropertyAndEquipmentImprovements" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="kymr_CollaborationIncome" name="CollaborationIncome" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="kymr_SupplementalCashFlowInformationRelatingToLeasesTableTextBlock" name="SupplementalCashFlowInformationRelatingToLeasesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="kymr_IncreaseOrDecreasePreFundedWarrants" name="IncreaseOrDecreasePreFundedWarrants" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="kymr_TenantIncentiveAllowanceReceivable" name="TenantIncentiveAllowanceReceivable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="kymr_FinanceLeaseLiabilityPaymentsDueAfterYearFour" name="FinanceLeaseLiabilityPaymentsDueAfterYearFour" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="kymr_ChangeInFairValueOfWarrantOfLiability" name="ChangeInFairValueOfWarrantOfLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="kymr_CollaborationTargetOneMember" name="CollaborationTargetOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="kymr_InitialResearchTermOfCollaboration" name="InitialResearchTermOfCollaboration" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="kymr_IncreaseDecreaseInContractWithCustomerAssetRelatedParties" name="IncreaseDecreaseInContractWithCustomerAssetRelatedParties" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="kymr_ContractWithCustomerLiabilityDeductions" name="ContractWithCustomerLiabilityDeductions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="kymr_SeriesB1PreferredStockMember" name="SeriesB1PreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="kymr_FairValueOfAvailableForSaleDebtSecuritiesContractualMaturityOfLessThanTwelveMonths" name="FairValueOfAvailableForSaleDebtSecuritiesContractualMaturityOfLessThanTwelveMonths" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="kymr_IncomeTaxDisclosureLineItems" name="IncomeTaxDisclosureLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="kymr_IssuanceOfCommonStockAtPrivatePlacementNetOfIssuanceCostShares" name="IssuanceOfCommonStockAtPrivatePlacementNetOfIssuanceCostShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="kymr_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantedInPeriodIntrinsicValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantedInPeriodIntrinsicValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="kymr_RemainingResearchTermOfCollaboration" name="RemainingResearchTermOfCollaboration" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="kymr_IssuanceOfCommonStockAtPrivatePlacementNetOfIssuanceCost" name="IssuanceOfCommonStockAtPrivatePlacementNetOfIssuanceCost" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="kymr_NonRefundableUpfrontPaymentReceived" name="NonRefundableUpfrontPaymentReceived" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="kymr_LandlordMember" name="LandlordMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="kymr_LesserOfPotentialOutcomeTwoMember" name="LesserOfPotentialOutcomeTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="kymr_RestrictedCashMember" name="RestrictedCashMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="kymr_AvailableForSaleSecuritiesCreditLosses" name="AvailableForSaleSecuritiesCreditLosses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="kymr_SignificantAccountingPoliciesLineItems" name="SignificantAccountingPoliciesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="kymr_SeriesAPreferredUnitsMember" name="SeriesAPreferredUnitsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="kymr_LeaseTerminationDate" name="LeaseTerminationDate" type="xbrli:dateItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="kymr_FairValueMeasurementsAbstract" name="FairValueMeasurementsAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="kymr_SignificantAccountingPoliciesPolicyTextBlock" name="SignificantAccountingPoliciesPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="kymr_NoncancelableFacilityLeaseAgreementMember" name="NoncancelableFacilityLeaseAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="kymr_PotentialReceivableMilestonePayments" name="PotentialReceivableMilestonePayments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="kymr_CommonStockPurchaseWarrants" name="CommonStockPurchaseWarrants" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="kymr_PrivateInvestmentInPublicEquityPipeMember" name="PrivateInvestmentInPublicEquityPipeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="kymr_CompoundCollaborationAgreementMember" name="CompoundCollaborationAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="kymr_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeitedInPeriodIntrinsicValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeitedInPeriodIntrinsicValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
</xsd:schema>
