-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 Ej81qM+6dmePlPAwM5aP3Vf4Nb/8h26q/Cr5KKipDD5pb8h6cZH7U08FpBk0M/v5
 BcVQsTHycCTcUUv14VZmdQ==

<SEC-DOCUMENT>0000908737-05-000546.txt : 20050714
<SEC-HEADER>0000908737-05-000546.hdr.sgml : 20050714
<ACCEPTANCE-DATETIME>20050714163510
ACCESSION NUMBER:		0000908737-05-000546
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20050712
FILED AS OF DATE:		20050714
DATE AS OF CHANGE:		20050714

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ADVANCED MAGNETICS INC
		CENTRAL INDEX KEY:			0000792977
		STANDARD INDUSTRIAL CLASSIFICATION:	IN VITRO & IN VIVO DIAGNOSTIC SUBSTANCES [2835]
		IRS NUMBER:				042742593
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0930

	BUSINESS ADDRESS:	
		STREET 1:		61 MOONEY ST
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02138
		BUSINESS PHONE:		6174972070

	MAIL ADDRESS:	
		STREET 1:		61 MOONEY ST
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02138

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Pereira Brian JG
		CENTRAL INDEX KEY:			0001298146

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-14732
		FILM NUMBER:		05954868

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		617-497-2070

	MAIL ADDRESS:	
		STREET 1:		C/O ADVANCED MAGNETICS, INC.
		STREET 2:		61 MOONEY STREET
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02138
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>pereira_form4july13ex.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2005-07-12</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000792977</issuerCik>
        <issuerName>ADVANCED MAGNETICS INC</issuerName>
        <issuerTradingSymbol>AVM</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001298146</rptOwnerCik>
            <rptOwnerName>Pereira Brian JG</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O ADVANCED MAGNETICS, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>61 MOONEY STREET</rptOwnerStreet2>
            <rptOwnerCity>CAMBRIDGE</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02138</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>10.80</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2005-07-12</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>60000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2015-07-12</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>60000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>83000</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">5,000 of the shares are exercisable on July 12, 2005. At the beginning of each following calendar month, beginning with
August 1, 2005, 5,000 of the remaining shares become exercisable, such that by June 1, 2006 all shares will be exercisable.</footnote>
        <footnote id="F2">The reporting person holds warrants to purchase an aggregate of 3,157 shares of common stock of Advanced Magnetics. Such
warrants have been previously reported and are not included in the 83,000 figure which represents options to purchase shares
of common stock of Advanced Magnetics.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Michael Avallone, attorney in fact</signatureName>
        <signatureDate>2005-07-13</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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