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  <p style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><b><font size="5" face="Times New Roman" style="font-size:18.0pt;font-weight:bold;">UNITED STATES</font></b></p>
  
  <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><b><font size="5" face="Times New Roman" style="font-size:18.0pt;font-weight:bold;">SECURITIES
  AND EXCHANGE COMMISSION</font></b></p>
  
  <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">WASHINGTON,
  DC 20549</font></b></p>
  
  <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><b><font size="5" face="Times New Roman" style="font-size:18.0pt;font-weight:bold;">FORM&nbsp;8-K</font></b></p>
  
  <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><b><font size="3" face="Times New Roman" style="font-size:12.0pt;font-weight:bold;">CURRENT REPORT PURSUANT</font></b></p>
  
  <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><b><font size="3" face="Times New Roman" style="font-size:12.0pt;font-weight:bold;">TO SECTION&nbsp;13 OR 15(D)&nbsp;OF THE</font></b></p>
  
  <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><b><font size="3" face="Times New Roman" style="font-size:12.0pt;font-weight:bold;">SECURITIES EXCHANGE ACT OF 1934</font></b></p>
  
  <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;letter-spacing:-.15pt;">Date of report (Date of earliest
  event reported):&#160; <b>April&nbsp;28,
  2008</b></font></p>
  
  <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><b><font size="5" face="Times New Roman" style="font-size:18.0pt;font-weight:bold;">Acusphere,&nbsp;Inc.</font></b></p>
  
  <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(Exact Name of
  Registrant as Specified in Its Charter)</font></p>
  
  <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">Delaware</font></b></p>
  
  <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;letter-spacing:-.15pt;">(State or Other Jurisdiction</font><font size="2" style="font-size:10.0pt;">  <font style="letter-spacing:-.15pt;">of Incorporation)</font></font></p>
  
  <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
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    <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;letter-spacing:-.15pt;">000-50405</font></b></p>
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    <p style="color:windowtext;margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:1.0pt;font-weight:bold;letter-spacing:-.15pt;">&nbsp;</font></b></p>
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    <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;letter-spacing:-.15pt;">04-3208947</font></b></p>
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    <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;letter-spacing:-.15pt;">(Commission File Number)</font></p>
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    <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;letter-spacing:-.15pt;">(IRS Employer Identification No.)</font></p>
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    <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
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    <p style="color:windowtext;margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
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    <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;letter-spacing:-.15pt;">500 Arsenal Street</font></b></p>
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    <p style="color:windowtext;margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
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    <p style="color:windowtext;margin:0in 0in .0001pt;"><b><font size="2" face="Times New Roman" style="font-size:1.0pt;font-weight:bold;letter-spacing:-.15pt;">&nbsp;</font></b></p>
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    <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;letter-spacing:-.15pt;">02472</font></b></p>
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    <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;letter-spacing:-.15pt;">(Address of Principal Executive Offices)</font></p>
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    <p style="color:windowtext;margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;letter-spacing:-.15pt;">&nbsp;</font></p>
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    <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;letter-spacing:-.15pt;">(Zip Code)</font></p>
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  <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">(617) 648-8800</font></b></p>
  
  <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;letter-spacing:-.15pt;">(</font><font size="2" style="font-size:10.0pt;">Registrant&#146;s Telephone Number, Including Area Code)</font></p>
  
  <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="color:windowtext;margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;letter-spacing:-.15pt;">&#160;&#160;&#160;&#160;&#160;&#160;&#160; Check the appropriate box
  below if the Form&nbsp;8-K filing is intended to simultaneously satisfy the
  filing obligation of the registrant under any of the following provisions:</font></p>
  
  <p style="color:windowtext;margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
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    <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Wingdings" style="font-size:10.0pt;letter-spacing:-.15pt;">o</font></p>
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    <p style="color:windowtext;margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;letter-spacing:-.15pt;">Written
    communications pursuant to Rule&nbsp;425 under the Securities Act (17 CFR
    230.425)</font></p>
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    <p style="color:windowtext;margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;letter-spacing:-.15pt;">Soliciting
    material pursuant to Rule&nbsp;14a-12 under the Exchange Act (17 CFR
    240.14a-12)</font></p>
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    <p style="color:windowtext;margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
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    <p style="color:windowtext;margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;letter-spacing:-.15pt;">Pre-commencement
    communications pursuant to Rule&nbsp;14d-2(b)&nbsp;under the Exchange Act (17
    CFR 240.14d-2(b))</font></p>
    </td>
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    <td width="5%" valign="top" style="padding:0in .7pt 0in .7pt;width:5.0%;">
    <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
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    <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Wingdings" style="font-size:10.0pt;letter-spacing:-.15pt;">o</font></p>
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    <td width="95%" valign="top" style="padding:0in .7pt 0in .7pt;width:95.0%;">
    <p style="color:windowtext;margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;letter-spacing:-.15pt;">Pre-commencement
    communications pursuant to Rule&nbsp;13e-4(c)&nbsp;under the Exchange Act (17
    CFR 240.13e-4(c))</font></p>
    </td>
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  <p style="border:none;color:white;margin:0in 0in .0001pt;padding:0in;"><font size="2" color="black" face="Times New Roman" style="color:windowtext;font-size:10.0pt;">&nbsp;</font></p>
  
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  <p style="color:white;margin:0in 0in .0001pt;"><font size="2" color="black" face="Times New Roman" style="color:windowtext;font-size:10.0pt;">&nbsp;</font></p>
  
  <div style="margin:0in 0in .0001pt;"><hr size="3" width="100%" noshade color="#010101" align="left"></div>
  
  </div>
  <!-- SEQ.=1,FOLIO='',FILE='C:\JMS\apadma\08-12793-1\task2899729\12793-1-ba.htm',USER='105432',CD='Apr 29 03:53 2008' -->
  
  
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  <p align="center" style="color:white;margin:0in 0in .0001pt;text-align:center;"><font size="2" color="black" face="Times New Roman" style="color:windowtext;font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="color:white;margin:0in 0in .0001pt;"><font size="2" color="black" face="Times New Roman" style="color:windowtext;font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="color:white;margin:0in 0in .0001pt;"><b><font size="2" color="black" face="Times New Roman" style="color:windowtext;font-size:10.0pt;font-weight:bold;">Item
  8.01&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
  Other Events.</font></b></p>
  
  <p style="color:white;margin:0in 0in .0001pt;"><font size="2" color="black" face="Times New Roman" style="color:windowtext;font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="color:windowtext;margin:0in 0in .0001pt;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">On
  April&nbsp;28, 2008, Acusphere,&nbsp;Inc. issued a press release announcing</font><font size="2" style="font-size:10.0pt;"> the submission of a New Drug Application
  (NDA) to the U.S. Food&nbsp;&amp; Drug Administration (FDA) for approval to
  market its lead product candidate, Imagify&#153; (Perflubutane Polymer Microspheres
  for Injectable Suspension)</font><font size="2" style="font-size:10.0pt;">. A copy of the press release is attached
  hereto as Exhibit&nbsp;99.1 and is incorporated by reference.</font></p>
  
  <p style="color:windowtext;margin:0in 0in .0001pt;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="color:windowtext;margin:0in 0in .0001pt;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">This Current Report on
  Form 8-K contains forward-looking statements, which are made pursuant to the
  safe harbor provisions of Section 21E of the Securities Exchange Act of 1934,
  including statements regarding the safety and efficacy of and commercial
  opportunity for Imagify. There can be no assurance that the FDA will accept as
  complete for review the Company&#146;s NDA for Imagify or that Imagify will be
  approved for the indication the Company is seeking, or at all.&#160; The Company's actual results may differ
  materially from those anticipated in these forward-looking statements based
  upon a number of factors, including anticipated operating losses and existing
  capital obligations, uncertainties associated with research, development,
  testing and related regulatory approvals, including uncertainties regarding
  regulatory evaluation of the Company's statistical analysis plan and clinical
  trial results and uncertainties regarding the potential effects of not
  achieving clinical endpoints, uncertainties regarding the cost, timing and
  ultimate success of the qualification of the Company's commercial manufacturing
  facility in accordance with applicable regulatory requirements, complex
  manufacturing, high quality requirements, lack of commercial manufacturing
  experience, dependence on third-party manufacturers, suppliers and
  collaborators, uncertainties associated with intellectual property,
  competition, loss of key personnel, uncertainties associated with market
  acceptance and adequacy of reimbursement, technological change and government
  regulation, and other risks and challenges detailed in the Company's filings
  with the U.S. Securities and Exchange Commission, including the Company's
  Annual Report on Form 10-K for the year ended December 31, 2007. Readers are
  cautioned not to place undue reliance on any forward-looking statements, which
  speak only as of the date of this Current Report on Form 8-K. The Company
  undertakes no obligation to publicly release the results of any revisions to
  these forward-looking statements that may be made to reflect events or
  circumstances that occur after the date of this Current Report on Form 8-K or
  to reflect the occurrence of unanticipated events. </font></p>
  
  <p style="color:windowtext;margin:0in 0in .0001pt;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="color:white;margin:0in 0in .0001pt;"><b><font size="2" color="black" face="Times New Roman" style="color:windowtext;font-size:10.0pt;font-weight:bold;">Item&nbsp;9.01&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
  Financial Statements and Exhibits.</font></b></p>
  
  <p style="color:windowtext;margin:0in 0in .0001pt;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="color:windowtext;margin:0in 0in .0001pt;text-autospace:none;text-indent:.5in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">(d)&nbsp; Exhibits.</font></p>
  
  <p style="color:windowtext;margin:0in 0in .0001pt;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
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    <p style="color:windowtext;margin:0in 0in .0001pt;text-autospace:none;"><b><font size="1" face="Times New Roman" style="font-size:8.0pt;font-weight:bold;">Exhibit&nbsp;No.</font></b></p>
    </td>
    <td width="2%" valign="bottom" style="padding:0in .7pt 0in .7pt;width:2.6%;">
    <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;text-autospace:none;"><b><font size="1" face="Times New Roman" style="font-size:1.0pt;font-weight:bold;">&nbsp;</font></b></p>
    </td>
    <td width="88%" valign="bottom" style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in .7pt 0in .7pt;width:88.4%;">
    <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;text-autospace:none;"><b><font size="1" face="Times New Roman" style="font-size:8.0pt;font-weight:bold;">Description</font></b></p>
    </td>
   </tr>
   <tr>
    <td width="9%" valign="top" style="border:none;padding:0in .7pt 0in .7pt;width:9.0%;">
    <p style="color:windowtext;margin:0in 0in .0001pt;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
    <td width="2%" valign="bottom" style="padding:0in .7pt 0in .7pt;width:2.6%;">
    <p style="color:windowtext;margin:0in 0in .0001pt;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
    <td width="88%" valign="top" style="border:none;padding:0in .7pt 0in .7pt;width:88.4%;">
    <p style="color:windowtext;margin:0in 0in .0001pt;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
   </tr>
   <tr>
    <td width="9%" valign="top" style="padding:0in .7pt 0in .7pt;width:9.0%;">
    <p style="color:windowtext;margin:0in 0in .0001pt;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;99.1</font></p>
    </td>
    <td width="2%" valign="bottom" style="padding:0in .7pt 0in .7pt;width:2.6%;">
    <p style="color:windowtext;margin:0in 0in .0001pt;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="88%" valign="top" style="padding:0in .7pt 0in .7pt;width:88.4%;">
    <p style="color:windowtext;margin:0in 0in .0001pt;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Press Release dated
    April&nbsp;28, 2008, filed herewith</font></p>
    </td>
   </tr>
  </table>
  
  <p style="color:windowtext;margin:0in 0in .0001pt;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">2</font></p>
  
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  </div>
  <!-- SEQ.=1,FOLIO='2',FILE='C:\JMS\apadma\08-12793-1\task2899729\12793-1-ba.htm',USER='105432',CD='Apr 29 03:53 2008' -->
  
  
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  <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">SIGNATURES</font></b></p>
  
  <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p style="color:windowtext;margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; Pursuant to the requirements of the Securities
  Exchange Act of 1934, the registrant has duly caused this report to be signed on
  its behalf by the undersigned hereunto duly authorized.</font></p>
  
  <p style="color:windowtext;margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <table border="0" cellspacing="0" cellpadding="0" width="100%" style="border-collapse:collapse;width:100.0%;">
   <tr>
    <td width="50%" valign="top" style="padding:0in .7pt 0in .7pt;width:50.42%;">
    <p style="color:windowtext;margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="49%" colspan="3" valign="top" style="padding:0in .7pt 0in .7pt;width:49.58%;">
    <p style="color:windowtext;margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">ACUSPHERE, INC.</font></p>
    </td>
   </tr>
   <tr>
    <td width="50%" valign="top" style="padding:0in .7pt 0in .7pt;width:50.42%;">
    <p style="color:windowtext;margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
    <td width="4%" valign="top" style="padding:0in .7pt 0in .7pt;width:4.4%;">
    <p style="color:windowtext;margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
    <td width="45%" colspan="2" valign="top" style="padding:0in .7pt 0in .7pt;width:45.18%;">
    <p style="color:windowtext;margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
   </tr>
   <tr>
    <td width="50%" valign="top" style="padding:0in .7pt 0in .7pt;width:50.42%;">
    <p style="color:windowtext;margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
    <td width="4%" valign="top" style="padding:0in .7pt 0in .7pt;width:4.4%;">
    <p style="color:windowtext;margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
    <td width="45%" colspan="2" valign="top" style="padding:0in .7pt 0in .7pt;width:45.18%;">
    <p style="color:windowtext;margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
   </tr>
   <tr>
    <td width="50%" valign="top" style="padding:0in .7pt 0in .7pt;width:50.42%;">
    <p style="color:windowtext;margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Dated: April&nbsp;29,
    2008</font></p>
    </td>
    <td width="4%" valign="top" style="padding:0in .7pt 0in .7pt;width:4.4%;">
    <p style="color:windowtext;margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">By: </font></p>
    </td>
    <td width="45%" colspan="2" valign="top" style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in .7pt 0in .7pt;width:45.18%;">
    <p style="color:windowtext;margin:0in 0in .0001pt;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">/s/ Lawrence A. Gyenes</font></p>
    </td>
   </tr>
   <tr>
    <td width="50%" valign="top" style="padding:0in .7pt 0in .7pt;width:50.42%;">
    <p style="color:windowtext;margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="4%" valign="top" style="padding:0in .7pt 0in .7pt;width:4.4%;">
    <p style="color:windowtext;margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="6%" valign="top" style="padding:0in .7pt 0in .7pt;width:6.98%;">
    <p style="color:windowtext;margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Name: </font></p>
    </td>
    <td width="38%" valign="top" style="padding:0in .7pt 0in .7pt;width:38.2%;">
    <p style="color:windowtext;margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Lawrence A. Gyenes</font></p>
    </td>
   </tr>
   <tr>
    <td width="50%" valign="top" style="padding:0in .7pt 0in .7pt;width:50.42%;">
    <p style="color:windowtext;margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="4%" valign="top" style="padding:0in .7pt 0in .7pt;width:4.4%;">
    <p style="color:windowtext;margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="6%" valign="top" style="padding:0in .7pt 0in .7pt;width:6.98%;">
    <p style="color:windowtext;margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Title: </font></p>
    </td>
    <td width="38%" valign="top" style="padding:0in .7pt 0in .7pt;width:38.2%;">
    <p style="color:windowtext;margin:0in 0in .0001pt;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Senior Vice President, Chief Financial <br>
    Officer and Secretary</font></p>
    </td>
   </tr>
  </table>
  
  <p style="color:windowtext;margin:0in 0in .0001pt 3.25in;text-indent:-3.25in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">3</font></p>
  
  <div style="color:windowtext;margin:0in 0in .0001pt;text-autospace:none;"><hr size="3" width="100%" noshade color="#010101" align="left"></div>
  
  </div>
  <!-- SEQ.=1,FOLIO='3',FILE='C:\JMS\apadma\08-12793-1\task2899729\12793-1-ba.htm',USER='105432',CD='Apr 29 03:53 2008' -->
  
  
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  <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;text-autospace:none;"><b><font size="2" face="Times New Roman" style="font-size:10.0pt;font-weight:bold;">EXHIBIT INDEX</font></b></p>
  
  <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <table border="0" cellspacing="0" cellpadding="0" width="100%" style="border-collapse:collapse;width:100.0%;">
   <tr>
    <td width="8%" valign="bottom" style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in .7pt 0in .7pt;width:8.6%;">
    <p style="color:windowtext;margin:0in 0in .0001pt;text-autospace:none;"><b><font size="1" face="Times New Roman" style="font-size:8.0pt;font-weight:bold;">Exhibit&nbsp;No.</font></b></p>
    </td>
    <td width="2%" valign="bottom" style="padding:0in .7pt 0in .7pt;width:2.16%;">
    <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;text-autospace:none;"><b><font size="1" face="Times New Roman" style="font-size:1.0pt;font-weight:bold;">&nbsp;</font></b></p>
    </td>
    <td width="89%" valign="bottom" style="border:none;border-bottom:solid windowtext 1.0pt;padding:0in .7pt 0in .7pt;width:89.24%;">
    <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;text-autospace:none;"><b><font size="1" face="Times New Roman" style="font-size:8.0pt;font-weight:bold;">Description</font></b></p>
    </td>
   </tr>
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    <td width="8%" valign="top" style="border:none;padding:0in .7pt 0in .7pt;width:8.6%;">
    <p style="color:windowtext;margin:0in 0in .0001pt;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
    <td width="2%" valign="bottom" style="padding:0in .7pt 0in .7pt;width:2.16%;">
    <p style="color:windowtext;margin:0in 0in .0001pt;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
    <td width="89%" valign="top" style="border:none;padding:0in .7pt 0in .7pt;width:89.24%;">
    <p style="color:windowtext;margin:0in 0in .0001pt;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
    </td>
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   <tr>
    <td width="8%" valign="top" style="padding:0in .7pt 0in .7pt;width:8.6%;">
    <p style="color:windowtext;margin:0in 0in .0001pt;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">99.1</font></p>
    </td>
    <td width="2%" valign="bottom" style="padding:0in .7pt 0in .7pt;width:2.16%;">
    <p style="color:windowtext;margin:0in 0in .0001pt;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:1.0pt;">&nbsp;</font></p>
    </td>
    <td width="89%" valign="top" style="padding:0in .7pt 0in .7pt;width:89.24%;">
    <p style="color:windowtext;margin:0in 0in .0001pt;text-autospace:none;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">Press Release dated
    April&nbsp;28, 2008, filed herewith</font></p>
    </td>
   </tr>
  </table>
  
  <p style="color:windowtext;margin:0in 0in .0001pt 3.25in;text-indent:-3.25in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">&nbsp;</font></p>
  
  <p align="center" style="color:windowtext;margin:0in 0in .0001pt;text-align:center;text-indent:0in;"><font size="2" face="Times New Roman" style="font-size:10.0pt;">4</font></p>
  
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metadata_documents: [{"type": "8-K", "sequence": "1", "filename": "a08-12793_18k.htm", "description": "8-K", "secsgml_size_bytes": 34932}]
metadata_filer: {"company-data": {"conformed-name": "ACUSPHERE INC", "cik": "0001115143", "assigned-sic": "2834", "irs-number": "043208947", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "8-K", "act": "34", "file-number": "000-50405", "film-number": "08782974"}, "business-address": {"street1": "500 ARSENAL ST", "city": "WATERTOWN", "state": "MA", "zip": "02472", "phone": "6175778800"}, "mail-address": {"street1": "500 ARSENAL ST", "city": "WATERTOWN", "state": "MA", "zip": "02472"}}
text: UNITED STATES
  SECURITIES
  AND EXCHANGE COMMISSION
  WASHINGTON,
  DC 20549
  FORM 8-K
  CURRENT REPORT PURSUANT
  TO SECTION 13 OR 15(D) OF THE
  SECURITIES EXCHANGE ACT OF 1934
  Date of report (Date of earliest
  event reported):
  April 28,
  2008
  Acusphere, Inc.
  (Exact Name of
  Registrant as Specified in Its Charter)
  Delaware
  (State or Other Jurisdiction
  of Incorporation)
  000-50405
  04-3208947
  (Commission File Number)
  (IRS Employer Identification No.)
  500 Arsenal Street
  Watertown, MA
  02472
  (Address of Principal Executive Offices)
  (Zip Code)
  (617) 648-8800
  (
  Registrant's Telephone Number, Including Area Code)
  Check the appropriate box
  below if the Form 8-K filing is intended to simultaneously satisfy the
  filing obligation of the registrant under any of the following provisions:
  o
  Written
    communications pursuant to Rule 425 under the Securities Act (17 CFR
    230.425)
  o
  Soliciting
    material pursuant to Rule 14a-12 under the Exchange Act (17 CFR
    240.14a-12)
  o
  Pre-commencement
    communications pursuant to Rule 14d-2(b) under the Exchange Act (17
    CFR 240.14d-2(b))
  o
  Pre-commencement
    communications pursuant to Rule 13e-4(c) under the Exchange Act (17
    CFR 240.13e-4(c))
  Item
  8.01              
  Other Events.
  On
  April 28, 2008, Acusphere, Inc. issued a press release announcing
  the submission of a New Drug Application
  (NDA) to the U.S. Food & Drug Administration (FDA) for approval to
  market its lead product candidate, Imagify™ (Perflubutane Polymer Microspheres
  for Injectable Suspension)
  . A copy of the press release is attached
  hereto as Exhibit 99.1 and is incorporated by reference.
  This Current Report on
  Form 8-K contains forward-looking statements, which are made pursuant to the
  safe harbor provisions of Section 21E of the Securities Exchange Act of 1934,
  including statements regarding the safety and efficacy of and commercial
  opportunity for Imagify. There can be no assurance that the FDA will accept as
  complete for review the Company's NDA for Imagify or that Imagify will be
  approved for the indication the Company is seeking, or at all.  The Company's actual results may differ
  materially from those anticipated in these forward-looking statements based
  upon a number of factors, including anticipated operating losses and existing
  capital obligations, uncertainties associated with research, development,
  testing and related regulatory approvals, including uncertainties regarding
  regulatory evaluation of the Company's statistical analysis plan and clinical
  trial results and uncertainties regarding the potential effects of not
  achieving clinical endpoints, uncertainties regarding the cost, timing and
  ultimate success of the qualification of the Company's commercial manufacturing
  facility in accordance with applicable regulatory requirements, complex
  manufacturing, high quality requirements, lack of commercial manufacturing
  experience, dependence on third-party manufacturers, suppliers and
  collaborators, uncertainties associated with intellectual property,
  competition, loss of key personnel, uncertainties associated with market
  acceptance and adequacy of reimbursement, technological change and government
  regulation, and other risks and challenges detailed in the Company's filings
  with the U.S. Securities and Exchange Commission, including the Company's
  Annual Report on Form 10-K for the year ended December 31, 2007. Readers are
  cautioned not to place undue reliance on any forward-looking statements, which
  speak only as of the date of this Current Report on Form 8-K. The Company
  undertakes no obligation to publicly release the results of any revisions to
  these forward-looking statements that may be made to reflect events or
  circumstances that occur after the date of this Current Report on Form 8-K or
  to reflect the occurrence of unanticipated events.
  Item 9.01              
  Financial Statements and Exhibits.
  (d)  Exhibits.
  Exhibit No.
  Description
  99.1
  Press Release dated
    April 28, 2008, filed herewith
  2
  SIGNATURES
  Pursuant to the requirements of the Securities
  Exchange Act of 1934, the registrant has duly caused this report to be signed on
  its behalf by the undersigned hereunto duly authorized.
  ACUSPHERE, INC.
  Dated: April 29,
    2008
  By:
  /s/ Lawrence A. Gyenes
  Name:
  Lawrence A. Gyenes
  Title:
  Senior Vice President, Chief Financial
  Officer and Secretary
  3
  EXHIBIT INDEX
  Exhibit No.
  Description
  99.1
  Press Release dated
    April 28, 2008, filed herewith
  4