Acusphere to Participate in Banc of America Securities 2005 Health Care Conference.

WATERTOWN, Mass. -- Acusphere, Inc. (NASDAQ:ACUS) announced today that it is scheduled to present at the Banc of America Securities 2005 Health Care Conference at 5:20 pm (PDST) on Wednesday, May 18, 2005 in Las Vegas, Nevada at The Four Seasons Hotel. Presenting for the Company will be John F. Thero, Senior Vice President and Chief Financial Officer.

A webcast of the Company's presentation will be available both live and on a recorded basis via a link provided at the Company's website www.acusphere.com on the Investor Relations page. The recording will be available through May 31, 2005.

About Acusphere, Inc.

Acusphere is a specialty pharmaceutical company that develops new drugs and improved formulations of existing drugs using its proprietary microparticle technology. Acusphere's three initial product candidates for which it has clinical data are designed to address unmet clinical needs within cardiology, oncology and asthma. Acusphere's lead product candidate, AI-700, is a cardiovascular drug in Phase 3 clinical development. AI-700 is designed to enable ultrasound to compete more effectively with nuclear stress testing, the leading procedure for detecting coronary heart disease. An estimated 10.7 million procedures are performed each year in the U.S. to detect coronary heart disease, the leading cause of death in the United States. Acusphere's product candidates have been created using proprietary technology that enables Acusphere to control the porosity and size of nanoparticles and microparticles in a versatile manner that enables particles to be customized to address the delivery needs of a variety of drugs. For more information about Acusphere visit the Company's web site at www.acusphere.com.

"Acusphere" is a trademark of Acusphere, Inc.

Forward-looking Statements

The presentation to be made at the above announced conference may contain forward-looking statements, including statements regarding the successful and timely completion of clinical trials, future financing needs, commercial prospects for the Company's product candidates and technology and prospects for new partnering and business relationships. 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, uncertainties associated with research, development, testing and related regulatory approvals, unproven markets, future capital needs and uncertainty of additional financing, competition, uncertainties associated with intellectual property, complex manufacturing, high quality requirements for clinical trial materials and the technical challenges associated with obtaining such material, dependence on third-party manufacturers, suppliers and collaborators, loss of key personnel, lack of sales and marketing experience, uncertainties associated with market acceptance and adequacy of reimbursement, technological change, 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 Quarterly Report on Form 10-Q for the quarter ended March 31, 2005. Readers are cautioned not to place undue reliance on any forward-looking statements, which speak only as of the date of such presentation. 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 such presentation or to reflect the occurrence of unanticipated events.