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            <filer>
                <filerCredentials>
                    <cik>0001840110</cik>
                    <ccc>XXXXXXXX</ccc>
                </filerCredentials>
            </filer>
            <liveTestFlag>LIVE</liveTestFlag>



        </filerInfo>
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        <issuerInfo>
            <issuerCik>0001597264</issuerCik>
            <issuerName>BLUEPRINT MEDICINES CORPORATION</issuerName>
            <secFileNumber>001-37359</secFileNumber>
            <issuerAddress>
                <ns2:street1>45 Sidney Street</ns2:street1>
                <ns2:city>Cambridge</ns2:city>
                <ns2:stateOrCountry>MA</ns2:stateOrCountry>
                <ns2:zipCode>02139</ns2:zipCode>
            </issuerAddress>
            <issuerContactPhone>(617) 374-7580</issuerContactPhone>
            <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>LEMUEL BECKER HEWES</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
            <relationshipsToIssuer>
                <relationshipToIssuer>Officer</relationshipToIssuer>
            </relationshipsToIssuer>
        </issuerInfo>
        <securitiesInformation>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <brokerOrMarketmakerDetails>
                <name>Morgan Stanley Smith Barney LLC Executive Financial Services</name>
                <address>
                    <ns2:street1>1 New York Plaza</ns2:street1>
                    <ns2:street2>8th Floor</ns2:street2>
                    <ns2:city>New York</ns2:city>
                    <ns2:stateOrCountry>NY</ns2:stateOrCountry>
                    <ns2:zipCode>10004</ns2:zipCode>
                </address>
            </brokerOrMarketmakerDetails>
            <noOfUnitsSold>5232</noOfUnitsSold>
            <aggregateMarketValue>458803.50</aggregateMarketValue>
            <noOfUnitsOutstanding>63906011</noOfUnitsOutstanding>
            <approxSaleDate>03/06/2025</approxSaleDate>
            <securitiesExchangeName>NASDAQ</securitiesExchangeName>
        </securitiesInformation>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>03/01/2025</acquiredDate>
            <natureOfAcquisitionTransaction>Restricted Stock</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>ISSUER</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>5232</amountOfSecuritiesAcquired>
            <paymentDate>03/01/2025</paymentDate>
            <natureOfPayment>Not Applicable</natureOfPayment>
        </securitiesToBeSold>
        <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>LEMUEL BECKER HEWES</name>
                <address>
                    <ns2:street1>45 Sidney Street</ns2:street1>
                    <ns2:city>Cambridge</ns2:city>
                    <ns2:stateOrCountry>MA</ns2:stateOrCountry>
                    <ns2:zipCode>02139</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>03/05/2025</saleDate>
            <amountOfSecuritiesSold>4863</amountOfSecuritiesSold>
            <grossProceeds>431832.94</grossProceeds>
        </securitiesSoldInPast3Months>
        <noticeSignature>
            <noticeDate>03/06/2025</noticeDate>
            <planAdoptionDates>
                <planAdoptionDate>03/01/2024</planAdoptionDate>
            </planAdoptionDates>
            <signature>/s/ Lemuel Becker Hewes</signature>
        </noticeSignature>
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144
0001840110
XXXXXXXX
LIVE
0001597264
BLUEPRINT MEDICINES CORPORATION
001-37359
45 Sidney Street
Cambridge
MA
02139
(617) 374-7580
LEMUEL BECKER HEWES
Officer
Common
Morgan Stanley Smith Barney LLC Executive Financial Services
1 New York Plaza
8th Floor
New York
NY
10004
5232
458803.50
63906011
03/06/2025
NASDAQ
Common
03/01/2025
Restricted Stock
ISSUER
N
5232
03/01/2025
Not Applicable
N
LEMUEL BECKER HEWES
45 Sidney Street
Cambridge
MA
02139
Common
03/05/2025
4863
431832.94
03/06/2025
03/01/2024
/s/ Lemuel Becker Hewes