AVANIR's Intellectual Property Strengthened by Additional Asthma/Allergy Patent

SAN DIEGO--(BUSINESS WIRE)--July 6, 2004--AVANIR Pharmaceuticals (AMEX:AVN) announced today that a patent relating to AVANIR's asthma/allergy program has been issued by the U.S. Patent and Trademark Office. U.S. Patent #6,759,425, entitled "Benzimidazole Compounds for Modulating IgE and Inhibiting Cellular Proliferation" covers a broad genus, method of treatment, pharmaceutical composition and method of preparation for AVANIR's lead compound, AVP 13358, and its active metabolite.

"The addition of this patent to our intellectual property portfolio reinforces AVANIR's position in the field of asthma and allergy therapeutics," said Jagadish Sircar, Ph.D., Vice President of Drug Discovery at AVANIR Pharmaceuticals. "The newly issued patent provides protection not only for our compound in clinical development, AVP 13358, but for a series of active compounds."

AVANIR successfully completed an initial Phase I clinical trial with the orally active drug candidate known as AVP 13358 earlier this year. Results of the trial reported in May 2004 indicate that AVP 13358 was well-tolerated at all single rising doses administered to healthy volunteers in the study. The study also demonstrated that AVP 13358 is detectable in the bloodstream at all doses administered and remains in circulation long enough to allow once or twice daily dosing.

AVANIR is developing AVP 13358 as a potential treatment for allergy and asthma by targeting IgE and other known mediators of allergy and asthma. Immunoglobulin epsilon, or IgE, is released by the immune system in response to allergen exposure. AVANIR's unique approach selectively down-regulates the production of allergen-specific IgE as well as another critical group of mediators called Th2 cytokines that are up-regulated during asthmatic or allergic episodes.

AVANIR Pharmaceuticals is a drug discovery and development company focused on novel treatments for chronic diseases. The Company's most advanced product candidate, Neurodex(TM), is in Phase III clinical development for pseudobulbar affect, and in Phase II clinical development for neuropathic pain. A potential treatment for allergy and asthma, AVP 13358, is in Phase I clinical development. 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.

The information contained in this press release, including any forward-looking statements contained herein, should be reviewed in conjunction with the Company's most recent Annual Report on Form 10-K and other publicly available information regarding the Company. Copies of such information are available from the Company upon request. Such publicly available information sets forth many risks and uncertainties related to the Company's business and technology. Forward-looking statements often contain such words like "estimate," "anticipate," "believe," "plan" or "expect." Our IgE modulation program competes with other research approaches and compounds under development by large pharmaceutical and biotechnology companies and is subject to risks and uncertainties including the unpredictable nature of clinical trials and the regulatory environment, and the impact of competitive products. Pre-clinical 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.

CONTACT: AVANIR Pharmaceuticals
Patrice Saxon, 858-622-5202 (Investor Relations)
psaxon@avanir.com

SOURCE: AVANIR Pharmaceuticals