content: <?xml version="1.0" encoding="UTF-8"?><edgarSubmission xmlns="http://www.sec.gov/edgar/ownership" xmlns:com="http://www.sec.gov/edgar/common">
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      <filerInfo>
        <filer>
          <filerCredentials>
            <cik>0001788919</cik>
            <ccc>XXXXXXXX</ccc>
          </filerCredentials>
        </filer>
        <liveTestFlag>LIVE</liveTestFlag>
  
  
  
      </filerInfo>
    </headerData>
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      <issuerInfo>
        <issuerCik>0001521036</issuerCik>
        <issuerName>Lantheus Holdings, Inc.</issuerName>
        <secFileNumber>001-36569</secFileNumber>
        <issuerAddress>
          <com:street1>331 TREBLE COVE ROAD</com:street1>
          <com:city>NORTH BILLERICA</com:city>
          <com:stateOrCountry>MA</com:stateOrCountry>
          <com:zipCode>01862</com:zipCode>
        </issuerAddress>
        <issuerContactPhone>978 671-8001</issuerContactPhone>
        <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>Maeusli Heinz Christoph</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
        <relationshipsToIssuer>
          <relationshipToIssuer>Director</relationshipToIssuer>
        </relationshipsToIssuer>
      </issuerInfo>
      <securitiesInformation>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <brokerOrMarketmakerDetails>
          <name>Fidelity Brokerage Services LLC</name>
          <address>
            <com:street1>900 Salem St</com:street1>
            <com:city>Smithfield</com:city>
            <com:stateOrCountry>RI</com:stateOrCountry>
            <com:zipCode>02917</com:zipCode>
          </address>
        </brokerOrMarketmakerDetails>
        <noOfUnitsSold>25692</noOfUnitsSold>
        <aggregateMarketValue>2015023.56</aggregateMarketValue>
        <noOfUnitsOutstanding>69312588</noOfUnitsOutstanding>
        <approxSaleDate>05/28/2024</approxSaleDate>
        <securitiesExchangeName>NASDAQ</securitiesExchangeName>
      </securitiesInformation>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>06/19/2021</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>5981</amountOfSecuritiesAcquired>
        <paymentDate>06/19/2021</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>07/01/2021</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>922</amountOfSecuritiesAcquired>
        <paymentDate>07/01/2021</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>10/01/2021</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>1308</amountOfSecuritiesAcquired>
        <paymentDate>10/01/2021</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>05/28/2024</acquiredDate>
        <natureOfAcquisitionTransaction>Option Granted - 06/19/2020</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>17481</amountOfSecuritiesAcquired>
        <paymentDate>05/28/2024</paymentDate>
        <natureOfPayment>Cash</natureOfPayment>
      </securitiesToBeSold>
      <nothingToReportFlagOnSecuritiesSoldInPast3Months>Y</nothingToReportFlagOnSecuritiesSoldInPast3Months>
      <noticeSignature>
        <noticeDate>05/28/2024</noticeDate>
        <planAdoptionDates>
          <planAdoptionDate>02/27/2024</planAdoptionDate>
        </planAdoptionDates>
        <signature>/s/ Jared Cook, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Heinz Maeusli</signature>
      </noticeSignature>
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text: 144
  0001788919
  XXXXXXXX
  LIVE
  0001521036
  Lantheus Holdings, Inc.
  001-36569
  331 TREBLE COVE ROAD
  NORTH BILLERICA
  MA
  01862
  978 671-8001
  Maeusli Heinz Christoph
  Director
  Common
  Fidelity Brokerage Services LLC
  900 Salem St
  Smithfield
  RI
  02917
  25692
  2015023.56
  69312588
  05/28/2024
  NASDAQ
  Common
  06/19/2021
  Restricted Stock Vesting
  Issuer
  N
  5981
  06/19/2021
  Compensation
  Common
  07/01/2021
  Restricted Stock Vesting
  Issuer
  N
  922
  07/01/2021
  Compensation
  Common
  10/01/2021
  Restricted Stock Vesting
  Issuer
  N
  1308
  10/01/2021
  Compensation
  Common
  05/28/2024
  Option Granted - 06/19/2020
  Issuer
  N
  17481
  05/28/2024
  Cash
  Y
  05/28/2024
  02/27/2024
  /s/ Jared Cook, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Heinz Maeusli