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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 DT7nArfNvD6y86CqHevKBriQSpCExdDv5aMJzxcxNIJ0R9WJQSaM9rc1wl9z4jJD
 LsJvWYgEw6nRw1lVkLlP8w==

<SEC-DOCUMENT>0001104659-08-068081.txt : 20081105
<SEC-HEADER>0001104659-08-068081.hdr.sgml : 20081105
<ACCEPTANCE-DATETIME>20081105110244
ACCESSION NUMBER:		0001104659-08-068081
CONFORMED SUBMISSION TYPE:	3
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20081103
FILED AS OF DATE:		20081105
DATE AS OF CHANGE:		20081105

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ACUSPHERE INC
		CENTRAL INDEX KEY:			0001115143
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				043208947
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		500 ARSENAL ST
		CITY:			WATERTOWN
		STATE:			MA
		ZIP:			02472
		BUSINESS PHONE:		6175778800

	MAIL ADDRESS:	
		STREET 1:		500 ARSENAL ST
		CITY:			WATERTOWN
		STATE:			MA
		ZIP:			02472

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			CEPHALON INC
		CENTRAL INDEX KEY:			0000873364
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		3
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-50405
		FILM NUMBER:		081162767

	BUSINESS ADDRESS:	
		STREET 1:		41 MOORES ROAD
		CITY:			FRAZER
		STATE:			PA
		ZIP:			19355
		BUSINESS PHONE:		6103440200

	MAIL ADDRESS:	
		STREET 1:		41 MOORES ROAD
		CITY:			FRAZER
		STATE:			PA
		ZIP:			19355
</SEC-HEADER>
<DOCUMENT>
<TYPE>3
<SEQUENCE>1
<FILENAME>a3.xml
<DESCRIPTION>3
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0203</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2008-11-03</periodOfReport>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0001115143</issuerCik>
        <issuerName>ACUSPHERE INC</issuerName>
        <issuerTradingSymbol>ACUS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0000873364</rptOwnerCik>
            <rptOwnerName>CEPHALON INC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>41 MOORES ROAD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>FRAZER</rptOwnerCity>
            <rptOwnerState>PA</rptOwnerState>
            <rptOwnerZipCode>19355</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>Senior Convertible Note</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>0.486</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2008-11-03</value>
            </exerciseDate>
            <expirationDate>
                <value>2009-11-03</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <footnoteId id="F1"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The note is convertible into common stock under certain circumstances at the option of the Reporting Person for a period of one year. The number of shares of common stock issuable upon conversion of any Conversion Amount (as defined below) shall be the greater of (i) the amount determined by dividing (x) such Conversion Amount by (y) $0.486 and (ii) such number of shares of common stock as shall represent immediately after giving effect to such conversion 51% of the common stock outstanding on a fully diluted basis (excluding options, rights and warrants with exercise prices greater than the greater of (a) three times the average closing price of the Common Stock during the ten trading day period immediately prior to such conversion or (b) $8.00). &quot;Conversion Amount&quot; means the sum of (A) the principal ($15,000,000), (B) accrued and unpaid interest with respect to such principal and (C) accrued and unpaid late charges with respect to such amount being converted.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ J. Kevin Buchi</signatureName>
        <signatureDate>2008-11-05</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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