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        <entityName>Capstan Therapeutics, Inc.</entityName>
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            <city>SAN DIEGO</city>
            <stateOrCountry>CA</stateOrCountry>
            <stateOrCountryDescription>CALIFORNIA</stateOrCountryDescription>
            <zipCode>92121</zipCode>
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        <issuerPhoneNumber>858-314-9188</issuerPhoneNumber>
        <jurisdictionOfInc>DELAWARE</jurisdictionOfInc>
        <issuerPreviousNameList>
            <previousName>Teefib Biosciences, Inc.</previousName>
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        <entityType>Corporation</entityType>
        <yearOfInc>
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            <value>2020</value>
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    <offeringData>
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            <industryGroupType>Biotechnology</industryGroupType>
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        <issuerSize>
            <revenueRange>Decline to Disclose</revenueRange>
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        <federalExemptionsExclusions>
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            <dateOfFirstSale>
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        <minimumInvestmentAccepted>0</minimumInvestmentAccepted>
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        <signatureBlock>
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            <signature>
                <issuerName>Capstan Therapeutics, Inc.</issuerName>
                <signatureName>/s/ Laura Shawver</signatureName>
                <nameOfSigner>Laura Shawver</nameOfSigner>
                <signatureTitle>President and CEO</signatureTitle>
                <signatureDate>2024-03-19</signatureDate>
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