content: <?xml version="1.0" encoding="UTF-8"?><edgarSubmission xmlns="http://www.sec.gov/edgar/ownership" xmlns:com="http://www.sec.gov/edgar/common">
    <!-- Generated by Workiva -->
    <headerData>
      <submissionType>144</submissionType>
      <filerInfo>
        <filer>
          <filerCredentials>
            <cik>0001802970</cik>
            <ccc>XXXXXXXX</ccc>
          </filerCredentials>
        </filer>
        <liveTestFlag>LIVE</liveTestFlag>
  
  
  
      </filerInfo>
    </headerData>
    <formData>
      <issuerInfo>
        <issuerCik>0001597264</issuerCik>
        <issuerName>BLUEPRINT MEDICINES CORPORATION</issuerName>
        <secFileNumber>001-37359</secFileNumber>
        <issuerAddress>
          <com:street1>45 Sidney Street</com:street1>
          <com:city>Cambridge</com:city>
          <com:stateOrCountry>MA</com:stateOrCountry>
          <com:zipCode>02139</com:zipCode>
        </issuerAddress>
        <issuerContactPhone>6173747580</issuerContactPhone>
        <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>Debra Bumpus</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
        <relationshipsToIssuer>
          <relationshipToIssuer>Officer</relationshipToIssuer>
        </relationshipsToIssuer>
      </issuerInfo>
      <securitiesInformation>
        <securitiesClassTitle>Common Stock</securitiesClassTitle>
        <brokerOrMarketmakerDetails>
          <name>J.P. Morgan Securities LLC</name>
          <address>
            <com:street1>390 Madison Avenue - 6th Floor</com:street1>
            <com:city>New York</com:city>
            <com:stateOrCountry>NY</com:stateOrCountry>
            <com:zipCode>10017</com:zipCode>
          </address>
        </brokerOrMarketmakerDetails>
        <noOfUnitsSold>87034</noOfUnitsSold>
        <aggregateMarketValue>9228215</aggregateMarketValue>
        <noOfUnitsOutstanding>62616902</noOfUnitsOutstanding>
        <approxSaleDate>06/21/2024</approxSaleDate>
        <securitiesExchangeName>NASDAQ</securitiesExchangeName>
      </securitiesInformation>
      <securitiesToBeSold>
        <securitiesClassTitle>Common Stock</securitiesClassTitle>
        <acquiredDate>03/01/2020</acquiredDate>
        <natureOfAcquisitionTransaction>RSU Vest</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>990</amountOfSecuritiesAcquired>
        <paymentDate>03/01/2020</paymentDate>
        <natureOfPayment>NA</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common Stock</securitiesClassTitle>
        <acquiredDate>03/01/2021</acquiredDate>
        <natureOfAcquisitionTransaction>RSU Vest</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>3292</amountOfSecuritiesAcquired>
        <paymentDate>03/01/2021</paymentDate>
        <natureOfPayment>NA</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common Stock</securitiesClassTitle>
        <acquiredDate>03/01/2022</acquiredDate>
        <natureOfAcquisitionTransaction>RSU Vest</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>3494</amountOfSecuritiesAcquired>
        <paymentDate>03/01/2022</paymentDate>
        <natureOfPayment>NA</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common Stock</securitiesClassTitle>
        <acquiredDate>03/01/2023</acquiredDate>
        <natureOfAcquisitionTransaction>RSU Vest</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>3599</amountOfSecuritiesAcquired>
        <paymentDate>03/01/2023</paymentDate>
        <natureOfPayment>NA</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common Stock</securitiesClassTitle>
        <acquiredDate>03/01/2024</acquiredDate>
        <natureOfAcquisitionTransaction>RSU Vest</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>2447</amountOfSecuritiesAcquired>
        <paymentDate>03/01/2024</paymentDate>
        <natureOfPayment>NA</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common Stock</securitiesClassTitle>
        <acquiredDate>06/21/2024</acquiredDate>
        <natureOfAcquisitionTransaction>Stock Option Exercise</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>13471</amountOfSecuritiesAcquired>
        <paymentDate>06/21/2024</paymentDate>
        <natureOfPayment>Cash</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common Stock</securitiesClassTitle>
        <acquiredDate>06/21/2024</acquiredDate>
        <natureOfAcquisitionTransaction>Stock Option Exercise</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>24200</amountOfSecuritiesAcquired>
        <paymentDate>06/21/2024</paymentDate>
        <natureOfPayment>Cash</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common Stock</securitiesClassTitle>
        <acquiredDate>06/21/2024</acquiredDate>
        <natureOfAcquisitionTransaction>Stock Option Exercise</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>15500</amountOfSecuritiesAcquired>
        <paymentDate>06/21/2024</paymentDate>
        <natureOfPayment>Cash</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common Stock</securitiesClassTitle>
        <acquiredDate>06/21/2024</acquiredDate>
        <natureOfAcquisitionTransaction>Stock Option Exercise</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>7041</amountOfSecuritiesAcquired>
        <paymentDate>06/21/2024</paymentDate>
        <natureOfPayment>Cash</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common Stock</securitiesClassTitle>
        <acquiredDate>06/21/2024</acquiredDate>
        <natureOfAcquisitionTransaction>Stock Option Exercise</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>13000</amountOfSecuritiesAcquired>
        <paymentDate>06/21/2024</paymentDate>
        <natureOfPayment>Cash</natureOfPayment>
      </securitiesToBeSold>
      <nothingToReportFlagOnSecuritiesSoldInPast3Months>Y</nothingToReportFlagOnSecuritiesSoldInPast3Months>
      <noticeSignature>
        <noticeDate>06/21/2024</noticeDate>
        <planAdoptionDates>
          <planAdoptionDate>03/13/2024</planAdoptionDate>
        </planAdoptionDates>
        <signature>/s/ J.P. Morgan Securities LLC as agent and attorney-in-fact for Debra Bumpus</signature>
      </noticeSignature>
    </formData>
  </edgarSubmission>
metadata_documents: [{"type": "144", "sequence": "1", "filename": "primary_doc.xml", "secsgml_size_bytes": 7658}]
text: 144
  0001802970
  XXXXXXXX
  LIVE
  0001597264
  BLUEPRINT MEDICINES CORPORATION
  001-37359
  45 Sidney Street
  Cambridge
  MA
  02139
  6173747580
  Debra Bumpus
  Officer
  Common Stock
  J.P. Morgan Securities LLC
  390 Madison Avenue - 6th Floor
  New York
  NY
  10017
  87034
  9228215
  62616902
  06/21/2024
  NASDAQ
  Common Stock
  03/01/2020
  RSU Vest
  Issuer
  N
  990
  03/01/2020
  NA
  Common Stock
  03/01/2021
  RSU Vest
  Issuer
  N
  3292
  03/01/2021
  NA
  Common Stock
  03/01/2022
  RSU Vest
  Issuer
  N
  3494
  03/01/2022
  NA
  Common Stock
  03/01/2023
  RSU Vest
  Issuer
  N
  3599
  03/01/2023
  NA
  Common Stock
  03/01/2024
  RSU Vest
  Issuer
  N
  2447
  03/01/2024
  NA
  Common Stock
  06/21/2024
  Stock Option Exercise
  Issuer
  N
  13471
  06/21/2024
  Cash
  Common Stock
  06/21/2024
  Stock Option Exercise
  Issuer
  N
  24200
  06/21/2024
  Cash
  Common Stock
  06/21/2024
  Stock Option Exercise
  Issuer
  N
  15500
  06/21/2024
  Cash
  Common Stock
  06/21/2024
  Stock Option Exercise
  Issuer
  N
  7041
  06/21/2024
  Cash
  Common Stock
  06/21/2024
  Stock Option Exercise
  Issuer
  N
  13000
  06/21/2024
  Cash
  Y
  06/21/2024
  03/13/2024
  /s/ J.P. Morgan Securities LLC as agent and attorney-in-fact for Debra Bumpus