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  <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_AdditionalSubleasePaymentsShareOfProfitsLandlord." name="AdditionalSubleasePaymentsShareOfProfitsLandlord." nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_IncreaseDecreaseInOperatingLeaseLiabilities" name="IncreaseDecreaseInOperatingLeaseLiabilities" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_OfficeAndLaboratorySpaceInCambridgeMassachusetts45SidneyStreetExpansionPremisesMember" name="OfficeAndLaboratorySpaceInCambridgeMassachusetts45SidneyStreetExpansionPremisesMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_ProceedsFromIssuanceOfCommonStockNetOfUnderwritingDiscountsCommissionsAndOfferingExpenses" name="ProceedsFromIssuanceOfCommonStockNetOfUnderwritingDiscountsCommissionsAndOfferingExpenses" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_DebtSecuritiesAvailableForSaleNumberOfPositions" name="DebtSecuritiesAvailableForSaleNumberOfPositions" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_DevelopmentClinicalSupplyMember" name="DevelopmentClinicalSupplyMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" xmlns="http://www.w3.org/2001/XMLSchema" />
  <element id="bpmc_NetProceedsFromStockOptionExercisesAndEmployeeStockPurchasePlan" name="NetProceedsFromStockOptionExercisesAndEmployeeStockPurchasePlan" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" xmlns="http://www.w3.org/2001/XMLSchema" />
</xsd:schema>
