<SEC-DOCUMENT>0001140361-15-033757.txt : 20150828
<SEC-HEADER>0001140361-15-033757.hdr.sgml : 20150828
<ACCEPTANCE-DATETIME>20150828130736
ACCESSION NUMBER:		0001140361-15-033757
CONFORMED SUBMISSION TYPE:	D
PUBLIC DOCUMENT COUNT:		1
ITEM INFORMATION:		<ITEMS>06b
FILED AS OF DATE:		20150828
DATE AS OF CHANGE:		20150828
EFFECTIVENESS DATE:		20150828

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Syndax Pharmaceuticals Inc
		CENTRAL INDEX KEY:			0001395937
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				320162505
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		D
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	021-246643
		FILM NUMBER:		151081275

	BUSINESS ADDRESS:	
		STREET 1:		460 TOTTEN POND ROAD
		STREET 2:		SUITE 650
		CITY:			WALTHAM
		STATE:			MA
		ZIP:			02451
		BUSINESS PHONE:		781-419-1400

	MAIL ADDRESS:	
		STREET 1:		460 TOTTEN POND ROAD
		STREET 2:		SUITE 650
		CITY:			WALTHAM
		STATE:			MA
		ZIP:			02451
</SEC-HEADER>
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        <entityName>Syndax Pharmaceuticals Inc</entityName>
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            <street2>SUITE 110</street2>
            <city>WALTHAM</city>
            <stateOrCountry>MA</stateOrCountry>
            <stateOrCountryDescription>MASSACHUSETTS</stateOrCountryDescription>
            <zipCode>02451</zipCode>
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    <relatedPersonsList>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>John</firstName>
                <lastName>Pallies</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>400 Totten Pond Road</street1>
                <street2>Suite 110</street2>
                <city>Waltham</city>
                <stateOrCountry>MA</stateOrCountry>
                <stateOrCountryDescription>MASSACHUSETTS</stateOrCountryDescription>
                <zipCode>02451</zipCode>
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            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
            </relatedPersonRelationshipList>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Luke</firstName>
                <lastName>Evnin, Ph.D.</lastName>
            </relatedPersonName>
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                <street1>400 Totten Pond Road</street1>
                <street2>Suite 110</street2>
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        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Kim</firstName>
                <lastName>Kamdar, Ph.D</lastName>
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            <relatedPersonRelationshipList>
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            <relatedPersonName>
                <firstName>Dennis</firstName>
                <lastName>Podlesak</lastName>
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            <relatedPersonRelationshipList>
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            </relatedPersonRelationshipList>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Ivor</firstName>
                <lastName>Royston, M.D.</lastName>
            </relatedPersonName>
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            <relatedPersonRelationshipList>
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        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Richard</firstName>
                <middleName>P</middleName>
                <lastName>Shea</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>400 Totten Pond Road</street1>
                <street2>Suite 110</street2>
                <city>Waltham</city>
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        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>George</firstName>
                <middleName>W</middleName>
                <lastName>Sledge, Jr., M.D.</lastName>
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            <relatedPersonAddress>
                <street1>400 Totten Pond Road</street1>
                <street2>Suite 110</street2>
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                <firstName>Michael</firstName>
                <lastName>Metzger</lastName>
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            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
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        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Henry</firstName>
                <lastName>Chen</lastName>
            </relatedPersonName>
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                <city>Waltham</city>
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        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Briggs</firstName>
                <lastName>Morrison, M.D.</lastName>
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            <relatedPersonRelationshipList>
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                <relationship>Director</relationship>
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    <offeringData>
        <industryGroup>
            <industryGroupType>Pharmaceuticals</industryGroupType>
        </industryGroup>
        <issuerSize>
            <revenueRange>Decline to Disclose</revenueRange>
        </issuerSize>
        <federalExemptionsExclusions>
            <item>06b</item>
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        <typeOfFiling>
            <newOrAmendment>
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            </newOrAmendment>
            <dateOfFirstSale>
                <value>2015-08-21</value>
            </dateOfFirstSale>
        </typeOfFiling>
        <durationOfOffering>
            <moreThanOneYear>false</moreThanOneYear>
        </durationOfOffering>
        <typesOfSecuritiesOffered>
            <isEquityType>true</isEquityType>
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        <businessCombinationTransaction>
            <isBusinessCombinationTransaction>false</isBusinessCombinationTransaction>
        </businessCombinationTransaction>
        <minimumInvestmentAccepted>0</minimumInvestmentAccepted>
        <salesCompensationList></salesCompensationList>
        <offeringSalesAmounts>
            <totalOfferingAmount>61252462</totalOfferingAmount>
            <totalAmountSold>61252462</totalAmountSold>
            <totalRemaining>0</totalRemaining>
        </offeringSalesAmounts>
        <investors>
            <hasNonAccreditedInvestors>false</hasNonAccreditedInvestors>
            <totalNumberAlreadyInvested>19</totalNumberAlreadyInvested>
        </investors>
        <salesCommissionsFindersFees>
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                <dollarAmount>0</dollarAmount>
            </salesCommissions>
            <findersFees>
                <dollarAmount>0</dollarAmount>
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        </salesCommissionsFindersFees>
        <useOfProceeds>
            <grossProceedsUsed>
                <dollarAmount>0</dollarAmount>
            </grossProceedsUsed>
        </useOfProceeds>
        <signatureBlock>
            <authorizedRepresentative>false</authorizedRepresentative>
            <signature>
                <issuerName>Syndax Pharmaceuticals Inc</issuerName>
                <signatureName>/s/ John Pallies</signatureName>
                <nameOfSigner>John Pallies</nameOfSigner>
                <signatureTitle>Chief Financial Officer</signatureTitle>
                <signatureDate>2015-08-28</signatureDate>
            </signature>
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