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      <liveTestFlag>LIVE</liveTestFlag>



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      <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>LENO SAM R</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
      <relationshipsToIssuer>
        <relationshipToIssuer>Director</relationshipToIssuer>
      </relationshipsToIssuer>
    </issuerInfo>
    <securitiesInformation>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <brokerOrMarketmakerDetails>
        <name>Fidelity Brokerage Services LLC</name>
        <address>
          <com:street1>900 Salem Street</com:street1>
          <com:city>Smithfield</com:city>
          <com:stateOrCountry>RI</com:stateOrCountry>
          <com:zipCode>02917</com:zipCode>
        </address>
      </brokerOrMarketmakerDetails>
      <noOfUnitsSold>7012</noOfUnitsSold>
      <aggregateMarketValue>568883.56</aggregateMarketValue>
      <noOfUnitsOutstanding>67540065</noOfUnitsOutstanding>
      <approxSaleDate>03/27/2023</approxSaleDate>
      <securitiesExchangeName>NASDAQ</securitiesExchangeName>
    </securitiesInformation>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>03/27/2023</acquiredDate>
      <natureOfAcquisitionTransaction>Options Granted - 05/06/2013</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>7012</amountOfSecuritiesAcquired>
      <paymentDate>03/27/2023</paymentDate>
      <natureOfPayment>Cash</natureOfPayment>
    </securitiesToBeSold>
    <nothingToReportFlagOnSecuritiesSoldInPast3Months>Y</nothingToReportFlagOnSecuritiesSoldInPast3Months>
    <noticeSignature>
      <noticeDate>03/27/2023</noticeDate>
      <planAdoptionDates>
        <planAdoptionDate>02/24/2023</planAdoptionDate>
      </planAdoptionDates>
      <signature>/s/ Gary Redman, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Sam Leno</signature>
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144
0001238660
XXXXXXXX
LIVE
0001521036
Lantheus Holdings, Inc.
001-36569
331 TREBLE COVE ROAD
NORTH BILLERICA
MA
01862
978 671-8001
LENO SAM R
Director
Common
Fidelity Brokerage Services LLC
900 Salem Street
Smithfield
RI
02917
7012
568883.56
67540065
03/27/2023
NASDAQ
Common
03/27/2023
Options Granted - 05/06/2013
Issuer
N
7012
03/27/2023
Cash
Y
03/27/2023
02/24/2023
/s/ Gary Redman, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Sam Leno