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          <ccc>XXXXXXXX</ccc>
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      <liveTestFlag>LIVE</liveTestFlag>


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      <issuerCik>0001888012</issuerCik>
      <issuerName>HilleVax, Inc.</issuerName>
      <secFileNumber>001-41365</secFileNumber>
      <issuerAddress>
        <com:street1>321 HARRISON AVE, SUITE 500</com:street1>
        <com:city>BOSTON</com:city>
        <com:stateOrCountry>MA</com:stateOrCountry>
        <com:zipCode>02118</com:zipCode>
      </issuerAddress>
      <issuerContactPhone>(617) 213-5054</issuerContactPhone>
      <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>HERSHBERG ROBERT</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
      <relationshipsToIssuer>
        <relationshipToIssuer>Officer</relationshipToIssuer>
        <relationshipToIssuer>Director</relationshipToIssuer>
      </relationshipsToIssuer>
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    <securitiesInformation>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <brokerOrMarketmakerDetails>
        <name>Charles Schwab &amp; Co., Inc.</name>
        <address>
          <com:street1>3000 Schwab Way</com:street1>
          <com:city>Westlake</com:city>
          <com:stateOrCountry>TX</com:stateOrCountry>
          <com:zipCode>76262</com:zipCode>
        </address>
      </brokerOrMarketmakerDetails>
      <noOfUnitsSold>72000</noOfUnitsSold>
      <aggregateMarketValue>1008000.00</aggregateMarketValue>
      <noOfUnitsOutstanding>48437001</noOfUnitsOutstanding>
      <approxSaleDate>01/22/2024</approxSaleDate>
      <securitiesExchangeName>NASDAQ</securitiesExchangeName>
    </securitiesInformation>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>02/01/2023</acquiredDate>
      <natureOfAcquisitionTransaction>Rights Repurchase</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>72000</amountOfSecuritiesAcquired>
      <paymentDate>02/01/2023</paymentDate>
      <natureOfPayment>N/A</natureOfPayment>
    </securitiesToBeSold>
    <nothingToReportFlagOnSecuritiesSoldInPast3Months>Y</nothingToReportFlagOnSecuritiesSoldInPast3Months>
    <noticeSignature>
      <noticeDate>01/22/2024</noticeDate>
      <planAdoptionDates>
        <planAdoptionDate>10/18/2023</planAdoptionDate>
      </planAdoptionDates>
      <signature>ROBERT M HERSHBERG</signature>
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144
0001274139
XXXXXXXX
LIVE
0001888012
HilleVax, Inc.
001-41365
321 HARRISON AVE, SUITE 500
BOSTON
MA
02118
(617) 213-5054
HERSHBERG ROBERT
Officer
Director
Common
Charles Schwab & Co., Inc.
3000 Schwab Way
Westlake
TX
76262
72000
1008000.00
48437001
01/22/2024
NASDAQ
Common
02/01/2023
Rights Repurchase
Issuer
N
72000
02/01/2023
N/A
Y
01/22/2024
10/18/2023
ROBERT M HERSHBERG