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        <submissionType>144</submissionType>
        <filerInfo>
            <filer>
                <filerCredentials>
                    <cik>0001841990</cik>
                    <ccc>XXXXXXXX</ccc>
                </filerCredentials>
            </filer>
            <liveTestFlag>LIVE</liveTestFlag>



        </filerInfo>
    </headerData>
    <formData>
        <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>36329</noOfUnitsSold>
            <aggregateMarketValue>1615913.92</aggregateMarketValue>
            <noOfUnitsOutstanding>109801397</noOfUnitsOutstanding>
            <approxSaleDate>09/23/2024</approxSaleDate>
            <securitiesExchangeName>NASDAQ</securitiesExchangeName>
        </securitiesInformation>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>09/23/2024</acquiredDate>
            <natureOfAcquisitionTransaction>Exercise of Stock Options</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>24000</amountOfSecuritiesAcquired>
            <paymentDate>09/23/2024</paymentDate>
            <natureOfPayment>Cash</natureOfPayment>
        </securitiesToBeSold>
        <securitiesToBeSold>
            <securitiesClassTitle>Common</securitiesClassTitle>
            <acquiredDate>09/11/2024</acquiredDate>
            <natureOfAcquisitionTransaction>Performance Stock Units</natureOfAcquisitionTransaction>
            <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
            <isGiftTransaction>N</isGiftTransaction>
            <amountOfSecuritiesAcquired>12329</amountOfSecuritiesAcquired>
            <paymentDate>09/11/2024</paymentDate>
            <natureOfPayment>N/A</natureOfPayment>
        </securitiesToBeSold>
        <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
        <securitiesSoldInPast3Months>
            <sellerDetails>
                <name>10b5-1 Sales for 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>09/11/2024</saleDate>
            <amountOfSecuritiesSold>111394</amountOfSecuritiesSold>
            <grossProceeds>4500244.20</grossProceeds>
        </securitiesSoldInPast3Months>
        <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>08/22/2024</saleDate>
            <amountOfSecuritiesSold>3412</amountOfSecuritiesSold>
            <grossProceeds>17640.04</grossProceeds>
        </securitiesSoldInPast3Months>
        <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>07/02/2024</saleDate>
            <amountOfSecuritiesSold>3503</amountOfSecuritiesSold>
            <grossProceeds>17374.88</grossProceeds>
        </securitiesSoldInPast3Months>
        <remarks>The securities to be sold will be received upon the exercise of stock options over the next three months. The dates of acquisition and payment will be the dates of exercise/sale.&#13;
</remarks>
        <noticeSignature>
            <noticeDate>09/23/2024</noticeDate>
            <planAdoptionDates>
                <planAdoptionDate>06/12/2024</planAdoptionDate>
            </planAdoptionDates>
            <signature>/s/ William Michael Flanagan</signature>
        </noticeSignature>
    </formData>
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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
36329
1615913.92
109801397
09/23/2024
NASDAQ
Common
09/23/2024
Exercise of Stock Options
Issuer
N
24000
09/23/2024
Cash
Common
09/11/2024
Performance Stock Units
Issuer
N
12329
09/11/2024
N/A
N
10b5-1 Sales for WILLIAM MICHAEL FLANAGAN
10578 Science Center Drive, Suite 125
San Diego
CA
92121
Common
09/11/2024
111394
4500244.20
WILLIAM MICHAEL FLANAGAN
10578 Science Center Drive, Suite 125
San Diego
CA
92121
Common
08/22/2024
3412
17640.04
WILLIAM MICHAEL FLANAGAN
10578 Science Center Drive, Suite 125
San Diego
CA
92121
Common
07/02/2024
3503
17374.88
The securities to be sold will be received upon the exercise of stock options over the next three months. The dates of acquisition and payment will be the dates of exercise/sale.
09/23/2024
06/12/2024
/s/ William Michael Flanagan