AVANIR Presents Data on Novel Anti-Inflammatory Compounds at Experimental Biology 2004; Orally Active Molecules Target Key Inflammatory Protein.

Business Editors/Health/Medical Writers

BIOWIRE2K

Experimental Biology 2004

SAN DIEGO--(BUSINESS WIRE)--April 19, 2004

AVANIR Pharmaceuticals (AMEX:AVN) presented data on its lead anti-inflammatory compounds at the Experimental Biology 2004 meeting organized by the Federation of American Societies for Experimental Biology (FASEB) in Washington, D.C., April 17-21, 2004. The AVANIR compounds target macrophage migration inhibitory factor (MIF), a pro-inflammatory cytokine that plays a critical role in inflammatory disorders such as rheumatoid arthritis, inflammatory bowel disease and psoriasis.

"We believe this is the first publicly presented data that demonstrates therapeutic efficacy of an orally active small molecule MIF inhibitor in established animal disease models," said Jagadish Sircar, Ph.D., Vice President of Drug Discovery at AVANIR Pharmaceuticals.

Two posters, Inhibition of Macrophage Migration Inhibitory Factor (MIF) Activities by AVP-13546, A Small Molecule Inhibitor, and Reduction of Multiple Pro-Inflammatory Mediators by an Orally Active Small Molecule Antagonist of Macrophage Migration Inhibitor Factor, AVP-13748, were presented today. The latter was also selected by FASEB as the subject of an oral presentation given on April 18th to the American Association of Immunologists.

AVANIR Pharmaceuticals, based in San Diego, is a drug discovery and development company focused on the development of treatments for chronic diseases. Further information about AVANIR can be found at www.avanir.com.

Except for the historical information presented herein, matters discussed in this press release contain forward-looking statements that are subject to certain risks and uncertainties that could cause actual results to differ materially from any future results, performance or achievements expressed or implied by such statements. Statements that are not historical facts, including statements that are preceded by, followed by, or that include such words as "estimate," "anticipate," "believe," "plan" or "expect" or similar statements are forward-looking statements. Risks and uncertainties for AVANIR Pharmaceuticals include risks associated with product discovery and development as well as risks shown in AVANIR's most recent Annual Report on Form 10-K and Quarterly Report on Form 10-Q and from time-to-time in other publicly available information regarding the company. Copies of such information are available from AVANIR upon request. Such publicly available information sets forth many risks and uncertainties related to AVANIR's business and technology. Our anti-inflammation research program is in the early stages of development and competes with other research approaches and compounds under development by large pharmaceutical and biotechnology companies. Preclinical research findings are not always supportable by evidence obtained from subsequent clinical trials. Final review decisions made by the FDA and other regulatory agencies concerning clinical trial results are unpredictable and outside the influence and/or control of the Company. The company disclaims any intent or obligations to update these forward-looking statements.