<SEC-DOCUMENT>0001140361-16-048251.txt : 20160120
<SEC-HEADER>0001140361-16-048251.hdr.sgml : 20160120
<ACCEPTANCE-DATETIME>20160120191921
ACCESSION NUMBER:		0001140361-16-048251
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20160115
FILED AS OF DATE:		20160120
DATE AS OF CHANGE:		20160120

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ARDELYX, INC.
		CENTRAL INDEX KEY:			0001437402
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				000000000
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		34175 ARDENWOOD BLVD.
		CITY:			FREMONT
		STATE:			CA
		ZIP:			94555
		BUSINESS PHONE:		510-745-7047

	MAIL ADDRESS:	
		STREET 1:		34175 ARDENWOOD BLVD.
		CITY:			FREMONT
		STATE:			CA
		ZIP:			94555

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	NTERYX INC
		DATE OF NAME CHANGE:	20080611

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Kaufmann Mark
		CENTRAL INDEX KEY:			0001611184

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-36485
		FILM NUMBER:		161352178

	MAIL ADDRESS:	
		STREET 1:		C/O ARDELYX, INC.
		STREET 2:		34175 ARDENWOOD BLVD, SUITE 100
		CITY:			FREMONT
		STATE:			CA
		ZIP:			94555
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc1.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2016-01-15</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001437402</issuerCik>
        <issuerName>ARDELYX, INC.</issuerName>
        <issuerTradingSymbol>ARDX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001611184</rptOwnerCik>
            <rptOwnerName>Kaufmann Mark</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O ARDELYX, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>34175 ARDENWOOD BLVD, SUITE 200</rptOwnerStreet2>
            <rptOwnerCity>FREMONT</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94555</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Financial Officer</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2015-08-31</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>686</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>13.991</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1282</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>10.55</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2016-01-15</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>102701</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <value>2026-01-15</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>102701</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>102701</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The shares were acquired under the Issuer's Employee Stock Purchase Plan on August 31, 2015.</footnote>
        <footnote id="F2">The option becomes exercisable as it vests and the shares subject to the option vest in 48 successive, equal monthly installments on each monthly anniversary of January 15, 2016, subject to the Reporting Person's continued employment or service relationship with the Issuer on each such vesting date.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Elizabeth Grammer, Attorney-in-Fact for Mark Kaufmann</signatureName>
        <signatureDate>2016-01-20</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
