Acusphere Schedules Conference Call to Discuss RAMP-1 Clinical Trial Results for AI-700.

WATERTOWN, Mass. -- Acusphere, Inc. (NASDAQ: ACUS) announced today that it has scheduled a conference call to discuss the results from the first of two Phase 3 clinical trials for AI-700, the RAMP-1 trial. The call is scheduled for Tuesday, June 6, 2006. It is scheduled to commence at 7:00 a.m. EDT, prior to the Tuesday sessions of the American Society of Echocardiography. Participating on this call will include Sherri Oberg, President and CEO of Acusphere, Richard Walovitch, Ph.D., Senior Vice President of Clinical Research of Acusphere, and Roxy Senior, M.D., Director of Echocardiology in the Department of Cardiology at Northwick Park Hospital and the Imperial College School of Medicine, London UK, a leading thought leader in contrast echocardiography and largest enroller of patients in the RAMP-1 trial. Following opening comments, callers will have the opportunity to ask questions of the presenters.

The conference call may be accessed by dialing 866-831-6291 for domestic callers and 617-213-8860 for international callers and providing the passcode 30295516. The webcast may be accessed by visiting the Investor Relations section of the Company's Web site at www.acusphere.com, and will be available for 30 days. A replay of the call will be available after the completion of the call on June 6, 2006. To access the replay, please dial 888-286-8010 for domestic callers and 617-801-6888 for international callers and provide the access code 84022360.

About AI-700

AI-700 is a cardiovascular drug designed to provide physicians with valuable information on myocardial perfusion. The Company is developing AI-700 to help improve stress echo, by enabling it to assess both wall motion and myocardial perfusion in one fast and convenient test. The Company believes that ultrasound with AI-700 has meaningful potential cost and convenience advantages when compared to nuclear stress tests, today's leading method of screening patients for coronary heart disease (CHD). AI-700 was designed using Acusphere's proprietary porous microsphere technology. AI-700 is a dry powder consisting of small, porous microspheres filled with a perfluorocarbon gas. These microspheres are made of a synthetic biodegradable polymer, called poly (D, L-lactide co-glycolide), or PLGA, that has been used in other drug delivery systems approved by the FDA. The microspheres are injected into the body by a bolus intravenous injection prior to ultrasound imaging. AI-700 was designed to be easy to use with commercially available ultrasound equipment and established imaging techniques.

About Acusphere, Inc.

Acusphere is a specialty pharmaceutical company that develops new drugs and improved formulations of existing drugs using its proprietary microsphere technology. Acusphere's three initial product candidates are designed to address large unmet clinical needs within cardiology, oncology and asthma. These product candidates were created using proprietary technology that enables Acusphere to control the porosity and size of nanoparticles and microspheres in a versatile manner that allows the microspheres 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

This press release 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 potential cost and convenience attributes of stress echocardiography with AI-700 and the ability of such procedures to effectively provide wall motion and myocardial perfusion information in a fast and easy to use test. All such forward-looking statements are made pursuant to the safe harbor provisions of Section 21E of the Securities Exchange Act of 1934. 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 the ultimate outcome of Acusphere's Phase 3 clinical trials for AI-700 and uncertainties regarding regulatory evaluation of the Company's statistical analysis plan and clinical trial results, unproven markets, future capital needs and uncertainty of additional financing, lack of sales and marketing experience, uncertainties associated with intellectual property, 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, 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 Quarterly Report on Form 10-Q for the quarter ended March 31, 2006. Readers are cautioned not to place undue reliance on any forward-looking statements, which speak only as of the date of this press release. 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 press release or to reflect the occurrence of unanticipated events.