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      <link:roleType roleURI="http://www.blueprintmedicines.com/role/DisclosureRestrictedCashDetails" id="DisclosureRestrictedCashDetails">
        <link:definition>40501 - Disclosure - Restricted Cash (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.blueprintmedicines.com/role/DisclosureTermLoanFutureMinimumPaymentsDetails" id="DisclosureTermLoanFutureMinimumPaymentsDetails">
        <link:definition>40802 - Disclosure - Term Loan - Future Minimum Payments (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.blueprintmedicines.com/role/DisclosureCommitmentsRentExpenseDetails" id="DisclosureCommitmentsRentExpenseDetails">
        <link:definition>41102 - Disclosure - Commitments - Rent Expense (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:linkbaseRef xlink:type="simple" xlink:href="bpmc-20180930_pre.xml" xlink:role="http://www.xbrl.org/2003/role/presentationLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" />
      <link:linkbaseRef xlink:type="simple" xlink:href="bpmc-20180930_def.xml" xlink:role="http://www.xbrl.org/2003/role/definitionLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" />
      <link:linkbaseRef xlink:type="simple" xlink:href="bpmc-20180930_lab.xml" xlink:role="http://www.xbrl.org/2003/role/labelLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" />
      <link:linkbaseRef xlink:type="simple" xlink:href="bpmc-20180930_cal.xml" xlink:role="http://www.xbrl.org/2003/role/calculationLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:title="Calculation Links, all" />
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  </xsd:annotation>
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  <xsd:import namespace="http://www.xbrl.org/dtr/type/non-numeric" schemaLocation="http://www.xbrl.org/dtr/type/nonNumeric-2009-12-16.xsd" />
  <xsd:import namespace="http://www.xbrl.org/2009/role/negated" schemaLocation="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd" />
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  <xsd:import namespace="http://www.xbrl.org/2003/instance" schemaLocation="http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd" />
  <xsd:import namespace="http://xbrl.org/2005/xbrldt" schemaLocation="http://www.xbrl.org/2005/xbrldt-2005.xsd" />
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  <element id="bpmc_AccruedCostsExternalResearchAndPreclinicalDevelopment" name="AccruedCostsExternalResearchAndPreclinicalDevelopment" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
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  <element id="bpmc_NonrefundableUpfrontPaymentReceived" name="NonrefundableUpfrontPaymentReceived" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_CollaborativeArrangementPeriodOfPriorNoticeToTerminateAgreement" name="CollaborativeArrangementPeriodOfPriorNoticeToTerminateAgreement" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_CollaborativeAgreementNumberOfDeliverables" name="CollaborativeAgreementNumberOfDeliverables" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_EmployeeStockPurchasePlan2015Member" name="EmployeeStockPurchasePlan2015Member" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_TermLoan2014Member" name="TermLoan2014Member" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_LeaseIncentivePayableNoncurrent" name="LeaseIncentivePayableNoncurrent" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfAdditionalSharesAuthorized" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfAdditionalSharesAuthorized" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_StockOptionAndIncentivePlan2015Member" name="StockOptionAndIncentivePlan2015Member" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_OfficeAndLaboratorySpaceInCambridgeMassachusettsMember" name="OfficeAndLaboratorySpaceInCambridgeMassachusettsMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_OperatingLeasesBaseAnnualRentInitial" name="OperatingLeasesBaseAnnualRentInitial" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_OperatingLeasesBaseAnnualRentMaximum" name="OperatingLeasesBaseAnnualRentMaximum" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_OperatingLeasesAllowanceForLeaseholdImprovements" name="OperatingLeasesAllowanceForLeaseholdImprovements" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_AccruedPropertyAndEquipmentCostsCurrent" name="AccruedPropertyAndEquipmentCostsCurrent" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_DebtInstrumentNumberOfTranches" name="DebtInstrumentNumberOfTranches" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_AnnualCumulativeIncreasePercentageOfNumberOfShareOfCommonStockIssuedAndOutstanding" name="AnnualCumulativeIncreasePercentageOfNumberOfShareOfCommonStockIssuedAndOutstanding" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_CommonStockIncreaseCapitalSharesReservedForFutureIssuance" name="CommonStockIncreaseCapitalSharesReservedForFutureIssuance" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_AccretionOfPremiumsAndDiscountsOnInvestments" name="AccretionOfPremiumsAndDiscountsOnInvestments" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_CashEquivalentAndAvailableForSaleDebtSecuritiesAmortizedCostBasis" name="CashEquivalentAndAvailableForSaleDebtSecuritiesAmortizedCostBasis" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_CashEquivalentsAndAvailableForSaleSecuritiesDebtSecuritiesFairValue" name="CashEquivalentsAndAvailableForSaleSecuritiesDebtSecuritiesFairValue" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_NumberOfCollaborationPrograms" name="NumberOfCollaborationPrograms" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_NumberOfCollaborationProgramsWithSelectedTargets" name="NumberOfCollaborationProgramsWithSelectedTargets" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_PriorToExerciseLicenseRightOptionMember" name="PriorToExerciseLicenseRightOptionMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_ExerciseOfLicenseOptionProductNotCommerciallySoldMember" name="ExerciseOfLicenseOptionProductNotCommerciallySoldMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_NumberOfLicenseOptionRights" name="NumberOfLicenseOptionRights" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_ExerciseOfLicenseRightOptionMember" name="ExerciseOfLicenseRightOptionMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_RocheMember" name="RocheMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_NumberOfCollaborationProgramsWithExclusiveCommercializationRights" name="NumberOfCollaborationProgramsWithExclusiveCommercializationRights" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_NumberOfCollaborationProgramsWithSpecifiedCommercializationRights" name="NumberOfCollaborationProgramsWithSpecifiedCommercializationRights" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_CollaborativeArrangementEligibleContingentOptionFeesAndMilestonePayments" name="CollaborativeArrangementEligibleContingentOptionFeesAndMilestonePayments" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_CollaborativeArrangementEligibleOptionFeesAndMilestonePaymentsPriorToLicensingAcrossAllPrograms" name="CollaborativeArrangementEligibleOptionFeesAndMilestonePaymentsPriorToLicensingAcrossAllPrograms" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_ExerciseOfLicenseOptionProductCommerciallySoldMember" name="ExerciseOfLicenseOptionProductCommerciallySoldMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_StockIssuanceCostsIncurredButNotYetPaidNoncashOrPartialNoncashTransaction" name="StockIssuanceCostsIncurredButNotYetPaidNoncashOrPartialNoncashTransaction" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_AchievedMilestonePaymentReceivedToBeRecognizedOverPerformancePeriod" name="AchievedMilestonePaymentReceivedToBeRecognizedOverPerformancePeriod" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_IncreaseDecreaseInDeferredRent" name="IncreaseDecreaseInDeferredRent" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_ReimbursableResearchAndDevelopmentCostsRecognized" name="ReimbursableResearchAndDevelopmentCostsRecognized" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
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  <element id="bpmc_SignificantAccountingPolicyPolicyTextBlock" name="SignificantAccountingPolicyPolicyTextBlock" nillable="true" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_FollowOnOfferingMember" name="FollowOnOfferingMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_OfficeAndLaboratorySpaceInCambridgeMassachusetts45SidneyStreetMember" name="OfficeAndLaboratorySpaceInCambridgeMassachusetts45SidneyStreetMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_OperatingLeasesRenewalTermExtensionsNumber" name="OperatingLeasesRenewalTermExtensionsNumber" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_OperatingLeasesSecurityDepositReductionSubjectToSatisfactionOfSpecifiedTermsAndConditions" name="OperatingLeasesSecurityDepositReductionSubjectToSatisfactionOfSpecifiedTermsAndConditions" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_OperatingLeasesTenantImprovementAllowance" name="OperatingLeasesTenantImprovementAllowance" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_OfficeAndLaboratorySpaceInCambridgeMassachusetts38SidneyStreetAnd45SidneyStreetMember" name="OfficeAndLaboratorySpaceInCambridgeMassachusetts38SidneyStreetAnd45SidneyStreetMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_DebtInstrumentFeePayableOnTotalLoanAdvancesPercentage" name="DebtInstrumentFeePayableOnTotalLoanAdvancesPercentage" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_DebtInstrumentPrepaymentFeePercentageLowEndOfRange" name="DebtInstrumentPrepaymentFeePercentageLowEndOfRange" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_DebtInstrumentPrepaymentFeePercentageHighEndOfRange" name="DebtInstrumentPrepaymentFeePercentageHighEndOfRange" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_LesseeOperatingLeaseTermOfContractSublease" name="LesseeOperatingLeaseTermOfContractSublease" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_MilestoneAxis" name="MilestoneAxis" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_MilestoneDomain" name="MilestoneDomain" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_InitialCashPaymentPerCollaborationAgreement" name="InitialCashPaymentPerCollaborationAgreement" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_OperatingLeasesSubleaseRentalPayableToLandLord" name="OperatingLeasesSubleaseRentalPayableToLandLord" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_IncreaseDecreaseInCustomerAssets" name="IncreaseDecreaseInCustomerAssets" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_NonrefundableUpfrontAndMilestonePaymentReceived" name="NonrefundableUpfrontAndMilestonePaymentReceived" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_NonrefundableMilestonePaymentReceived" name="NonrefundableMilestonePaymentReceived" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_CashEquivalentsAndAvailableForSaleAccumulatedGrossUnrealizedLossBeforeTax" name="CashEquivalentsAndAvailableForSaleAccumulatedGrossUnrealizedLossBeforeTax" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_CStoneMember" name="CStoneMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_DevelopmentAndRegulatoryMilestonesMember" name="DevelopmentAndRegulatoryMilestonesMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_SalesBasedMilestonesMember" name="SalesBasedMilestonesMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_CollaborativeArrangementEligibleMilestonePayments" name="CollaborativeArrangementEligibleMilestonePayments" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_LicensedProductTermFromFirstCommercialSale" name="LicensedProductTermFromFirstCommercialSale" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_ReversalOfCumulativeMilestoneRevenueNotOccurForDevelopmentalMilestone" name="ReversalOfCumulativeMilestoneRevenueNotOccurForDevelopmentalMilestone" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_CumulativeCatchUpOfRevenueForDevelopmentalMilestoneRecognized" name="CumulativeCatchUpOfRevenueForDevelopmentalMilestoneRecognized" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_NumberOfMaterialsComponents" name="NumberOfMaterialsComponents" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_NumberOfMaterialPromises" name="NumberOfMaterialPromises" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_NumberOfPerformanceObligation" name="NumberOfPerformanceObligation" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_EmployeeStockPurchasePlanMember" name="EmployeeStockPurchasePlanMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_ScheduleOfCompensationCostForShareBasedPaymentArrangementsAllocationOfShareBasedCompensationCostsByTypeOfAwardsTableTextBlock" name="ScheduleOfCompensationCostForShareBasedPaymentArrangementsAllocationOfShareBasedCompensationCostsByTypeOfAwardsTableTextBlock" nillable="true" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_AlexionMember" name="AlexionMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_RevenueCollaborativeArrangementsUpfrontPayment" name="RevenueCollaborativeArrangementsUpfrontPayment" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_RevenueCollaborativeArrangementsNonSubstantiveMilestonePayment" name="RevenueCollaborativeArrangementsNonSubstantiveMilestonePayment" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_RevenueCollaborativeArrangementsSubstantiveMilestonePayment" name="RevenueCollaborativeArrangementsSubstantiveMilestonePayment" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_SecurityDepositReleased" name="SecurityDepositReleased" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_CollaborativeArrangementReductionFromTotalOperatingExpenses" name="CollaborativeArrangementReductionFromTotalOperatingExpenses" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_PreCommercialAccrualCurrent" name="PreCommercialAccrualCurrent" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
</xsd:schema>
