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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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<SEC-DOCUMENT>0001140361-10-038657.txt : 20100927
<SEC-HEADER>0001140361-10-038657.hdr.sgml : 20100927
<ACCEPTANCE-DATETIME>20100927164736
ACCESSION NUMBER:		0001140361-10-038657
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100923
FILED AS OF DATE:		20100927
DATE AS OF CHANGE:		20100927

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BREY ROBERT N
		CENTRAL INDEX KEY:			0001459724

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-16929
		FILM NUMBER:		101091295

	MAIL ADDRESS:	
		STREET 1:		29 EMMONS DRIVE
		STREET 2:		SUITE C-10
		CITY:			PRINCETON
		STATE:			NJ
		ZIP:			08540

	FORMER NAME:	
		FORMER CONFORMED NAME:	Brey Robert N
		DATE OF NAME CHANGE:	20090325

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			SOLIGENIX, INC.
		CENTRAL INDEX KEY:			0000812796
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				411505029
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		29 EMMONS DRIVE
		STREET 2:		SUITE C-10
		CITY:			PRINCETON
		STATE:			NJ
		ZIP:			08540
		BUSINESS PHONE:		609-538-8200

	MAIL ADDRESS:	
		STREET 1:		29 EMMONS DRIVE
		STREET 2:		SUITE C-10
		CITY:			PRINCETON
		STATE:			NJ
		ZIP:			08540

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	DOR BIOPHARMA INC
		DATE OF NAME CHANGE:	20020329

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ENDOREX CORP
		DATE OF NAME CHANGE:	19960916

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	IMMUNOTHERAPEUTICS INC
		DATE OF NAME CHANGE:	19920703
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc1.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-09-23</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000812796</issuerCik>
        <issuerName>SOLIGENIX, INC.</issuerName>
        <issuerTradingSymbol>SNGX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001459724</rptOwnerCik>
            <rptOwnerName>BREY ROBERT N</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>29 EMMONS DRIVE SUITE C-10</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>PRINCETON</rptOwnerCity>
            <rptOwnerState>NJ</rptOwnerState>
            <rptOwnerZipCode>08540</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Science Officer &amp; Sr VP</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable></nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option (Right to Buy)</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>0.232</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2010-09-23</value>
                <footnoteId id="F1"/>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>850000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2010-09-23</value>
            </exerciseDate>
            <expirationDate>
                <value>2020-06-30</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>850000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>850000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The option grant was approved by the compensation committee of the board of directors of Soligenix, Inc. (the &quot;Company&quot;) on July 1, 2010, subject to stockholder approval of an amendment to the Company's 2005 Equity Incentive Plan (the &quot;Plan&quot;) to increase the maximum number of shares of common stock available for issuance under the Plan.  The Company's stockholders approved the amendment to the Plan on September 23, 2010.  The stock option vested as to 212,500 shares on July 1, 2010 with the remainder vesting quarterly in equal amounts on each three (3) month anniversary of July 1, 2010 for the next three years.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Robert N. Brey</signatureName>
        <signatureDate>2010-09-23</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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