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  <element id="bpmc_DevelopmentMilestoneSecondLicensedProductMember" name="DevelopmentMilestoneSecondLicensedProductMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_CommercialMilestoneMember" name="CommercialMilestoneMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_ResearchAndDevelopmentCostsIncurredUnderResearchPlanCollaborativePartnerFundingPercentagePerAgreement" name="ResearchAndDevelopmentCostsIncurredUnderResearchPlanCollaborativePartnerFundingPercentagePerAgreement" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <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" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_SeriesaWarrantsMember" name="SeriesaWarrantsMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_SeriesBWarrantsMember" name="SeriesBWarrantsMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_WarrantTerm" name="WarrantTerm" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_StockIssuedDuringPeriodSharesNewIssuesUnderwriters" name="StockIssuedDuringPeriodSharesNewIssuesUnderwriters" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_TermLoan2014Member" name="TermLoan2014Member" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_SeriesAndSeriesBWarrantsMember" name="SeriesAndSeriesBWarrantsMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_NumberOfCommonSharesExercisableFromWarrants" name="NumberOfCommonSharesExercisableFromWarrants" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_NumberOfWarrantsForCommonStockCancelled" name="NumberOfWarrantsForCommonStockCancelled" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_WarrantsDisclosureTextBlock" name="WarrantsDisclosureTextBlock" nillable="true" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" 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_ReclassificationOfWarrantLiabilityToAdditionalPaidInCapital" name="ReclassificationOfWarrantLiabilityToAdditionalPaidInCapital" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" 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" 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="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_ShareBasedCompensationArrangementByShareBasedPaymentAwardForfeitureRate" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardForfeitureRate" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_ReimbursableResearchAndDevelopmentCosts" name="ReimbursableResearchAndDevelopmentCosts" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" 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_UnbilledReceivablesIncludingReimbursableCostsCurrent" name="UnbilledReceivablesIncludingReimbursableCostsCurrent" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" 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_MilestoneAchievementPaymentsReceivable" name="MilestoneAchievementPaymentsReceivable" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_LicensedProductRoyaltyTermFromFirstCommercialSaleOption1" name="LicensedProductRoyaltyTermFromFirstCommercialSaleOption1" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_LicensedProductRoyaltyTermFromFirstCommercialSaleOption2" name="LicensedProductRoyaltyTermFromFirstCommercialSaleOption2" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_ExtensionPeriodExpiredOnPriorLease" name="ExtensionPeriodExpiredOnPriorLease" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" 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_AverageMaturityOfAvailableForSaleSecurity" name="AverageMaturityOfAvailableForSaleSecurity" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_RocheCollaborationAndLicenseArrangementMember" name="RocheCollaborationAndLicenseArrangementMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_AlexionCollaborativeArrangementMember" name="AlexionCollaborativeArrangementMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" 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_NumberOfAdditionalCollaborationProgramsToSelectTargets" name="NumberOfAdditionalCollaborationProgramsToSelectTargets" 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" 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" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_RocheMember" name="RocheMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" 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_RefundProvisionsWithinCollaborationAgreement" name="RefundProvisionsWithinCollaborationAgreement" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_NumberOfCollaborationProgramsStartedInFirstHalfOfYear" name="NumberOfCollaborationProgramsStartedInFirstHalfOfYear" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
</xsd:schema>
