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>0001762144</cik>
            <ccc>XXXXXXXX</ccc>
          </filerCredentials>
        </filer>
        <liveTestFlag>LIVE</liveTestFlag>
  
  
  
      </filerInfo>
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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>Gerard Ber</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
        <relationshipsToIssuer>
          <relationshipToIssuer>Director</relationshipToIssuer>
        </relationshipsToIssuer>
      </issuerInfo>
      <securitiesInformation>
        <securitiesClassTitle>Common Shares</securitiesClassTitle>
        <brokerOrMarketmakerDetails>
          <name>J.P. Morgan Securities LLC</name>
          <address>
            <com:street1>390 Madison Avenue</com:street1>
            <com:street2>6th Floor</com:street2>
            <com:city>New York</com:city>
            <com:stateOrCountry>NY</com:stateOrCountry>
            <com:zipCode>10017</com:zipCode>
          </address>
        </brokerOrMarketmakerDetails>
        <noOfUnitsSold>15500</noOfUnitsSold>
        <aggregateMarketValue>1508615</aggregateMarketValue>
        <noOfUnitsOutstanding>69430642</noOfUnitsOutstanding>
        <approxSaleDate>08/12/2024</approxSaleDate>
        <securitiesExchangeName>NASDAQ</securitiesExchangeName>
      </securitiesInformation>
      <securitiesToBeSold>
        <securitiesClassTitle>Common Shares</securitiesClassTitle>
        <acquiredDate>06/19/2020</acquiredDate>
        <natureOfAcquisitionTransaction>Conversion of Progenics shares into Lantheus shares post merger</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>15500</amountOfSecuritiesAcquired>
        <paymentDate>06/19/2020</paymentDate>
        <natureOfPayment>N/A</natureOfPayment>
      </securitiesToBeSold>
      <nothingToReportFlagOnSecuritiesSoldInPast3Months>Y</nothingToReportFlagOnSecuritiesSoldInPast3Months>
      <noticeSignature>
        <noticeDate>08/12/2024</noticeDate>
        <planAdoptionDates>
          <planAdoptionDate>05/07/2024</planAdoptionDate>
        </planAdoptionDates>
        <signature>/s/ J.P. Morgan Securities LLC as agent and attorney-in-fact for Gerard Ber</signature>
      </noticeSignature>
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text: 144
  0001762144
  XXXXXXXX
  LIVE
  0001521036
  Lantheus Holdings, Inc.
  001-36569
  331 Treble Cove Road
  North Billerica
  MA
  01862
  978-671-8001
  Gerard Ber
  Director
  Common Shares
  J.P. Morgan Securities LLC
  390 Madison Avenue
  6th Floor
  New York
  NY
  10017
  15500
  1508615
  69430642
  08/12/2024
  NASDAQ
  Common Shares
  06/19/2020
  Conversion of Progenics shares into Lantheus shares post merger
  Issuer
  N
  15500
  06/19/2020
  N/A
  Y
  08/12/2024
  05/07/2024
  /s/ J.P. Morgan Securities LLC as agent and attorney-in-fact for Gerard Ber