-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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<SEC-DOCUMENT>0001209191-09-048629.txt : 20091014
<SEC-HEADER>0001209191-09-048629.hdr.sgml : 20091014
<ACCEPTANCE-DATETIME>20091014184813
ACCESSION NUMBER:		0001209191-09-048629
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20091012
FILED AS OF DATE:		20091014
DATE AS OF CHANGE:		20091014

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Lyons C Neil
		CENTRAL INDEX KEY:			0001324648

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-15070
		FILM NUMBER:		091120092

	MAIL ADDRESS:	
		STREET 1:		C/O REGENERX BIOPHARMACEUTICALS, INC
		STREET 2:		3 BETHESDA METRO CENTER - SUITE 630
		CITY:			BETHESDA
		STATE:			MD
		ZIP:			20814

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			REGENERX BIOPHARMACEUTICALS INC
		CENTRAL INDEX KEY:			0000707511
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				521253406
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		3 BETHESDA METRO CENTER
		STREET 2:		SUITE 700
		CITY:			BETHESDA
		STATE:			MD
		ZIP:			20814
		BUSINESS PHONE:		3019611992

	MAIL ADDRESS:	
		STREET 1:		3 BETHESDA METRO CENTER
		STREET 2:		SUITE 700
		CITY:			BETHESDA
		STATE:			MD
		ZIP:			20814

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ALPHA 1 BIOMEDICALS INC
		DATE OF NAME CHANGE:	19950719
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>FORM 4 SUBMISSION
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2009-10-12</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000707511</issuerCik>
        <issuerName>REGENERX BIOPHARMACEUTICALS INC</issuerName>
        <issuerTradingSymbol>RGN</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001324648</rptOwnerCik>
            <rptOwnerName>Lyons C Neil</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O REGENERX BIOPHARMACEUTICALS, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>3 BETHESDA METRO CENTER, SUITE 630</rptOwnerStreet2>
            <rptOwnerCity>BETHESDA</rptOwnerCity>
            <rptOwnerState>MD</rptOwnerState>
            <rptOwnerZipCode>20814</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>CFO &amp; Treasurer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Options (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>0.76</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2009-10-12</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>75000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2016-10-12</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>75000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>75000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Options granted under the RegeneRx Biopharmaceuticals, Inc. Amended and Restated 2000 Stock Option and Incentive Plan vest over four years in four equal annual installments beginning with the first anniversary of the date of grant.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ C. Neil Lyons</signatureName>
        <signatureDate>2009-10-14</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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