<SEC-DOCUMENT>0000899243-16-033011.txt : 20161109
<SEC-HEADER>0000899243-16-033011.hdr.sgml : 20161109
<ACCEPTANCE-DATETIME>20161109160515
ACCESSION NUMBER:		0000899243-16-033011
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20161107
FILED AS OF DATE:		20161109
DATE AS OF CHANGE:		20161109

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			CytomX Therapeutics, Inc.
		CENTRAL INDEX KEY:			0001501989
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				000000000
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		343 OYSTER POINT BLVD.
		STREET 2:		SUITE 100
		CITY:			SOUTH SAN FRANCISCO
		STATE:			CA
		ZIP:			94080
		BUSINESS PHONE:		650.515.3185

	MAIL ADDRESS:	
		STREET 1:		343 OYSTER POINT BLVD.
		STREET 2:		SUITE 100
		CITY:			SOUTH SAN FRANCISCO
		STATE:			CA
		ZIP:			94080

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Exter Neil
		CENTRAL INDEX KEY:			0001620014

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-37587
		FILM NUMBER:		161984215

	MAIL ADDRESS:	
		STREET 1:		29 NEWBURY STREET
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02116
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>FORM 4 SUBMISSION
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2016-11-07</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001501989</issuerCik>
        <issuerName>CytomX Therapeutics, Inc.</issuerName>
        <issuerTradingSymbol>CTMX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001620014</rptOwnerCik>
            <rptOwnerName>Exter Neil</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>29 NEWBURY STREET, 3RD FLOOR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02116</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2016-11-07</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>0</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F2"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">On November 7, 2016, Third Rock Ventures, L.P. (&quot;TRV&quot;) distributed, for no consideration, 1,000,000 shares of Common Stock of the Issuer (the &quot;Shares&quot;) to its limited partners and to Third Rock Ventures GP, L.P. (&quot;TRV GP&quot;), the general partner of TRV, representing each such partner's pro rata interest in such Shares. On the same date, TRV GP distributed, for no consideration, the Shares it received in the distribution by TRV to its partners, representing each such partner's pro rata interest in such Shares. All of the aforementioned distributions were made in accordance with the exemptions afforded by Rules 16a-13 and 16a-9 of the Securities Exchange Act of 1934, as amended.</footnote>
        <footnote id="F2">The reporting person is a partner of TRV GP, which is the general partner of TRV. The reporting person disclaims beneficial ownership over the shares held by TRV, except to the extent of his pecuniary interest therein, if any, and this report shall not be deemed an admission that he is the beneficial owner of such shares.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Neil Exter</signatureName>
        <signatureDate>2016-11-09</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
