AVANIR Pharmaceuticals Added to 2005 Russell Indices.

SAN DIEGO -- AVANIR Pharmaceuticals (AMEX: AVN) today announced that the Company has been added to the Russell 3000(R), Russell 2000(R) and the newly created Russell Microcap(TM) Index. AVANIR was added to the indices as part of Frank Russell Company's annual reconstitution of U.S. equity indexes. The index membership, which was announced July 1, 2005, will remain in effect for one year.

Since 1984, the annual reconstitution of the Russell indexes captures the 3,000 largest U.S. stocks, ranking them by total market capitalization to create the Russell 3000. The largest 1,000 companies in the ranking comprise the Russell 1000 Index while the remaining 2,000 companies become the widely used Russell 2000 Index.

Russell indexes are used by managers for index funds and as benchmarks for both passive and active investment strategies. According to the Frank Russell Company, more than $360 billion is invested in index funds based on Russell's indexes and an additional $850 billion is benchmarked to them. Investment managers who oversee these funds purchase shares of member stocks according to that company's weighting in the particular index.

AVANIR Pharmaceuticals is a pharmaceutical company focused on developing and commercializing novel therapeutic products for the treatment of chronic diseases. AVANIR's product candidates address therapeutic markets that include central nervous system and cardiovascular disorders, inflammation, and infectious disease. AVANIR recently submitted to the FDA the last modules of a "rolling" new drug application for Neurodex(TM) for the treatment of pseudobulbar affect. Additionally, AVANIR has initiated a double-blind, placebo-controlled, multicenter, Phase III clinical trial of Neurodex in patients with diabetic neuropathic pain. Recently, AVANIR partnered its preclinical research and development program for inflammatory disease with Novartis. The Company's first commercialized product, Abreva(R), is marketed in North America by GlaxoSmithKline Consumer Healthcare and is the leading over-the-counter product for the treatment of cold sores. Further information about AVANIR can be found at www.avanir.com.

Statements in this press release 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 that are subject to certain risks and uncertainties that could cause actual results to differ materially from the future results expressed or implied by such statements. There can be no assurance that AVANIR's new drug application for Neurodex(TM) will be accepted for filing by the FDA, that Neurodex will receive regulatory approval, or that even if such regulatory approval is received, that AVANIR will be able to market Neurodex successfully. Final review decisions made by the FDA and other regulatory agencies concerning clinical trial results are often unpredictable and outside the influence and/or control of the company. Risks and uncertainties also include the risks set forth in AVANIR's most recent Annual Report on Form 10-K and subsequent Quarterly Reports on Form 10-Q and from time-to-time in other publicly available information regarding the Company. Copies of this information are available from AVANIR upon request. AVANIR disclaims any intent or obligation to update these forward-looking statements.