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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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 PYUgsYo/IAXir2NIkwLgaw==

<SEC-DOCUMENT>0001209191-06-042249.txt : 20060725
<SEC-HEADER>0001209191-06-042249.hdr.sgml : 20060725
<ACCEPTANCE-DATETIME>20060725134917
ACCESSION NUMBER:		0001209191-06-042249
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20060721
FILED AS OF DATE:		20060725
DATE AS OF CHANGE:		20060725

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ALTEON INC /DE
		CENTRAL INDEX KEY:			0000878903
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				133304550
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		6 CAMPUS DRIVE
		CITY:			PARSIPPANY
		STATE:			NJ
		ZIP:			07054
		BUSINESS PHONE:		2019345000

	MAIL ADDRESS:	
		STREET 1:		6 CAMPUS DRIVE
		CITY:			PARSIPPANY
		STATE:			NJ
		ZIP:			07054

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			GENENTECH INC
		CENTRAL INDEX KEY:			0000318771
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-16043
		FILM NUMBER:		06978567

	BUSINESS ADDRESS:	
		STREET 1:		1 DNA WAY
		CITY:			SOUTH SAN FRANCISCO
		STATE:			CA
		ZIP:			94080
		BUSINESS PHONE:		650-225-1000

	MAIL ADDRESS:	
		STREET 1:		1 DNA WAY
		STREET 2:		.
		CITY:			SOUTH SAN FRANCISCO
		STATE:			CA
		ZIP:			94080
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>bpa22257_bpa2ai.xml
<DESCRIPTION>MAIN DOCUMENT DESCRIPTION
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2006-07-21</periodOfReport>

    <issuer>
        <issuerCik>0000878903</issuerCik>
        <issuerName>ALTEON INC /DE</issuerName>
        <issuerTradingSymbol>ALT</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0000318771</rptOwnerCik>
            <rptOwnerName>GENENTECH INC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1 DNA WAY</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>SOUTH SAN FRANCISCO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94080</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2006-07-21</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>1</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>13492349</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>14290663</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Genentech entered into an Agreement and Plan of Merger, dated April 19, 2006, with Alteon, Inc., Alteon Merger Sub, Inc., and HaptoGuard, Inc. under which we agreed to restructure our nonvoting Preferred Stock position in Alteon in exchange for milestone payments, royalties and a right of first negotiation on certain compounds.  As part of the merger which closed on July 21, 2006, a certain portion of our Preferred Stock was converted into 13,492,349 shares of Alteon common stock, a certain portion of our Preferred Stock was transferred to HaptoGuard, Inc. and our remaining Preferred Stock was canceled.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Stephen G. Juelsgaard, Executive Vice President, General Counsel, Secretary and Chief Compliance Officer</signatureName>
        <signatureDate>2006-07-25</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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