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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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<SEC-DOCUMENT>0001140361-09-025694.txt : 20091112
<SEC-HEADER>0001140361-09-025694.hdr.sgml : 20091111
<ACCEPTANCE-DATETIME>20091112151025
ACCESSION NUMBER:		0001140361-09-025694
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20090918
FILED AS OF DATE:		20091112
DATE AS OF CHANGE:		20091112

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Biotex Pharma Investments, LLC
		CENTRAL INDEX KEY:			0001467543

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-16929
		FILM NUMBER:		091176699

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		212-763-5550

	MAIL ADDRESS:	
		STREET 1:		220 WEST 42ND STREET
		STREET 2:		6TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10036

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>2009-09-18</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001467543</rptOwnerCik>
            <rptOwnerName>Biotex Pharma Investments, LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>220 WEST 42ND STREET</rptOwnerStreet1>
            <rptOwnerStreet2>6TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10036</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2009-09-18</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>D</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>250000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>.2653</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>18750000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes></footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Robert Kessler</signatureName>
        <signatureDate>2009-10-11</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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