-----BEGIN PRIVACY-ENHANCED MESSAGE-----
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>0000930413-11-000531.txt : 20110128
<SEC-HEADER>0000930413-11-000531.hdr.sgml : 20110128
<ACCEPTANCE-DATETIME>20110128185335
ACCESSION NUMBER:		0000930413-11-000531
CONFORMED SUBMISSION TYPE:	5
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20101231
FILED AS OF DATE:		20110128
DATE AS OF CHANGE:		20110128

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Davit Paul Stephen
		CENTRAL INDEX KEY:			0001323791

	FILING VALUES:
		FORM TYPE:		5
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-12957
		FILM NUMBER:		11557198

	MAIL ADDRESS:	
		STREET 1:		DORSEY & WHITNEY LLP 250 PARK AVENUE
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10177

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ENZON PHARMACEUTICALS INC
		CENTRAL INDEX KEY:			0000727510
		STANDARD INDUSTRIAL CLASSIFICATION:	BIOLOGICAL PRODUCTS (NO DIAGNOSTIC SUBSTANCES) [2836]
		IRS NUMBER:				222372868
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		685 ROUTE 202/206
		CITY:			BRIDGEWATER
		STATE:			NJ
		ZIP:			08807
		BUSINESS PHONE:		908 541 8671

	MAIL ADDRESS:	
		STREET 1:		685 ROUTE 202/206
		STREET 2:		ATT:  GENERAL COUNSEL
		CITY:			BRIDGEWATER
		STATE:			NJ
		ZIP:			08807

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ENZON PHARMACEUTICALS  INC
		DATE OF NAME CHANGE:	20021211

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ENZON PHARMACEUTICAL  INC
		DATE OF NAME CHANGE:	20021210

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ENZON INC
		DATE OF NAME CHANGE:	19920703
</SEC-HEADER>
<DOCUMENT>
<TYPE>5
<SEQUENCE>1
<FILENAME>c64178_5.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>5</documentType>

    <periodOfReport>2010-12-31</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <form3HoldingsReported>0</form3HoldingsReported>

    <form4TransactionsReported>0</form4TransactionsReported>

    <issuer>
        <issuerCik>0000727510</issuerCik>
        <issuerName>ENZON PHARMACEUTICALS INC</issuerName>
        <issuerTradingSymbol>ENZN</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001323791</rptOwnerCik>
            <rptOwnerName>Davit Paul Stephen</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O ENZON PHARMACEUTICALS,</rptOwnerStreet1>
            <rptOwnerStreet2>685 RTE. 202/206</rptOwnerStreet2>
            <rptOwnerCity>BRIDGEWATER</rptOwnerCity>
            <rptOwnerState>NJ</rptOwnerState>
            <rptOwnerZipCode>08807</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Exec. Vice Pres. HR</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-09-30</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>5</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>785</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>8.908</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>106341.1651</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Purchase of shares under the Issuer's 2007 Employee Stock Purchase Plan, which is exempt under Rule 16b 3(c).</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Andrew Rackear, Attorney-In-Fact</signatureName>
        <signatureDate>2011-01-28</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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