December 2, 2003

News Release: Aerogen, Inc. Receives FDA Approval for U.S. Marketing of the Aeroneb(R) Go Nebulizer for Respiratory Therapy in the Home Setting

Aerogen, Inc. (Nasdaq: AEGND) today announced that it has received 510(k) clearance from the Food and Drug Administration ('FDA') to market its Aeroneb(R) Go Nebulizer ('Aeroneb Go'). The Aeroneb Go is a fast, efficient, simple-to-use device developed for the millions of patients worldwide that require nebulizer treatments in and away from home. The product will be featured at the upcoming American Association for Respiratory Care ('AARC') 49th Annual International Respiratory Congress beginning December 8th, 2003 in Las Vegas, Nevada. The Aeroneb Go was designed to eliminate many of the problems associated with current methods of aerosol delivery. Unlike many compressor, ultrasonic, or mesh-based nebulizers, the Aeroneb Go allows patients to complete their treatments quickly, with minimal wasted medication, and delivers a high-quality respirable aerosol. The product incorporates Aerogen's OnQ(TM) Aerosol Generator, the same trusted electronic micropump technology as that contained within the Aeroneb(R) Professional Nebulizer System used in hospitals worldwide. In addition, the product's easy assembly, silent aerosolization and ease of cleaning simplify treatments for patients and their caregivers and assure discreet therapy in any setting. Together, these advantages offer the potential to increase patient compliance with prescribed medications and improve patient quality of life.

'U.S. regulatory clearance of the product is a significant milestone for the Company, and is the next step toward commercialization of this product through our exclusive U.S. partner, Medical Industries America,'said Jane E. Shaw, Ph.D., Chairman and CEO of Aerogen.

The Aeroneb Go Nebulizer, for use by pediatric and adult patients, is cleared for use with physician-prescribed solutions for inhalation that are approved for use with general-purpose nebulizers. It is Aerogen's second-generation home nebulizer and will replace the Aeroneb(R) Portable Nebulizer System, which was commercialized in the United States in June 2001. The product will be marketed in the U.S., as well as in the major market countries of Europe and Japan under an exclusive agreement with Medical Industries America, Inc, one of the leading suppliers of nebulizers in the U.S. home care market and an emerging leader worldwide. The Aeroneb Go is CE marked, and Aerogen has made initial commercial shipments of the product in Norway through its distributor Normed AS.

There are more than 50 million patients worldwide who suffer from respiratory disorders including asthma, chronic obstructive pulmonary disease and cystic fibrosis, for whom over 2.5 million nebulizers are prescribed annually. In the U.S. alone, over four million respiratory patients require frequent, often daily, nebulizer therapy for the treatment of their conditions, requiring between 30 minutes and three hours of daily administration time.

Aerogen, a specialty pharmaceutical company, develops nebulizer products based on its OnQ(TM) Aerosol Generator technology to improve the treatment of respiratory disorders in the acute care setting. Aerogen also has development collaborations with pharmaceutical and biotechnology companies for the delivery via nebulizers or inhalers of novel compounds that treat respiratory and other disorders. Aerogen currently markets products that include the Aeroneb(R) Professional Nebulizer System, for use in the hospital, and the Aeroneb(R) Portable Nebulizer System, for home use. Aerogen's first drug product candidate in the acute care setting, inhaled amikacin for pulmonary infections, is currently in Phase 2 clinical trials. Additional products are in the feasibility and pre-clinical stages of development. Aerogen is headquartered in Mountain View, California, with a campus in Galway, Ireland. For more information, visit www.aerogen.com.

To the extent any statements made in this release relate to information that is not historical, these statements are necessarily forward-looking. As such, they are subject to the occurrence of many events outside of the Company's control and other uncertainties, and are subject to various risk factors that could cause the Company's actual results to differ materially from those expressed in any forward-looking statement. The risk factors include, without limitation, the need for additional funding, the inherent risks of product development, clinical outcomes, regulatory risks and risks related to proprietary rights, market acceptance and competition, and are described in the Company's reports and other filings with the U.S. Securities and Exchange Commission, including its Form 10-Q for the quarter ended September 30, 2003, filed November 14, 2003

SOURCE Aerogen, Inc.

Jane E. Shaw, Ph.D., +1-650-864-7333, for Aerogen, Inc.

WEBSITE This email address is being protected from spambots. You need JavaScript enabled to view it.