AVANIR Amends Terms of Existing Warrant; Warrant to Expire if Not Exercised by July 26, 2005

SAN DIEGO--(BUSINESS WIRE)--May 31, 2005--AVANIR Pharmaceuticals (AMEX:AVN) today announced that the holder of its existing Class G warrant has until July 26, 2005 to exercise the warrant for 757,050 shares of Class A common stock. On May 27th, 2005, AVANIR filed a registration statement with the Securities and Exchange Commission to register for resale the underlying common shares issuable upon the exercise of the Class G warrant. AVANIR will receive $1,097,722 if the holder timely exercises its rights to purchase all of the shares underlying the warrants. In exchange for granting these registration rights, AVANIR and the warrant holder agreed to increase the warrant exercise price from $1.37 to $1.45 per share.

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 expects to submit the final module of its rolling new drug application to the U.S. Food and Drug Administration for its lead product candidate, Neurodex(TM), in mid-2005. 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.

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 like "estimate," "anticipate," "believe," "intend," "plan," or "expect" or similar statements are forward-looking statements. Forward looking statements include, but are not limited to, risks associates with the timing of the Company's new drug application for Neurodex, regulatory decisions by the FDA for the Company's drug candidates, milestones and royalties earned from licensees, and results of clinical trials or product development efforts, as well as risks described in the Company's most recent Annual Report on Form 10-K and in subsequent quarterly reports 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. The company disclaims any intent or obligation to update these forward-looking statements.

    CONTACT: AVANIR Pharmaceuticals
             Patrice Saxon, 858-622-5202

    SOURCE: AVANIR Pharmaceuticals