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            <filer>
                <filerCredentials>
                    <cik>0001841990</cik>
                    <ccc>XXXXXXXX</ccc>
                </filerCredentials>
            </filer>
            <liveTestFlag>LIVE</liveTestFlag>



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        <issuerInfo>
            <issuerCik>0001599901</issuerCik>
            <issuerName>AVIDITY BIOSCIENCES INC</issuerName>
            <secFileNumber>001-39321</secFileNumber>
            <issuerAddress>
                <ns2:street1>10578 Science Center Drive, Suite 125</ns2:street1>
                <ns2:city>San Diego</ns2:city>
                <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                <ns2:zipCode>92121</ns2:zipCode>
            </issuerAddress>
            <issuerContactPhone>8584017900</issuerContactPhone>
            <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>WILLIAM MICHAEL FLANAGAN</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>20000</noOfUnitsSold>
            <aggregateMarketValue>600800.00</aggregateMarketValue>
            <noOfUnitsOutstanding>120212301</noOfUnitsOutstanding>
            <approxSaleDate>03/11/2025</approxSaleDate>
            <securitiesExchangeName>NASDAQ</securitiesExchangeName>
        </securitiesInformation>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>03/11/2025</acquiredDate>
            <natureOfAcquisitionTransaction>Exercise of Stock Options</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>20000</amountOfSecuritiesAcquired>
            <paymentDate>03/11/2025</paymentDate>
            <natureOfPayment>Cash</natureOfPayment>
        </securitiesToBeSold>
        <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>WILLIAM MICHAEL FLANAGAN</name>
                <address>
                    <ns2:street1>10578 Science Center Drive, Suite 125</ns2:street1>
                    <ns2:city>San Diego</ns2:city>
                    <ns2:stateOrCountry>CA</ns2:stateOrCountry>
                    <ns2:zipCode>92121</ns2:zipCode>
                </address>
            </sellerDetails>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <saleDate>01/21/2025</saleDate>
            <amountOfSecuritiesSold>5672</amountOfSecuritiesSold>
            <grossProceeds>162191.97</grossProceeds>
        </securitiesSoldInPast3Months>
        <noticeSignature>
            <noticeDate>03/11/2025</noticeDate>
            <planAdoptionDates>
                <planAdoptionDate>06/12/2024</planAdoptionDate>
            </planAdoptionDates>
            <signature>/s/ William Michael Flanagan</signature>
        </noticeSignature>
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144
0001841990
XXXXXXXX
LIVE
0001599901
AVIDITY BIOSCIENCES INC
001-39321
10578 Science Center Drive, Suite 125
San Diego
CA
92121
8584017900
WILLIAM MICHAEL FLANAGAN
Officer
Common
Morgan Stanley Smith Barney LLC Executive Financial Services
1 New York Plaza
8th Floor
New York
NY
10004
20000
600800.00
120212301
03/11/2025
NASDAQ
Common
03/11/2025
Exercise of Stock Options
Issuer
N
20000
03/11/2025
Cash
N
WILLIAM MICHAEL FLANAGAN
10578 Science Center Drive, Suite 125
San Diego
CA
92121
Common
01/21/2025
5672
162191.97
03/11/2025
06/12/2024
/s/ William Michael Flanagan