AVANIR Announces Neurodex Phase III Trial Results Published in Annals of Neurology.

SAN DIEGO -- AVANIR Pharmaceuticals (NASDAQ:AVNR) announced today that results of a pivotal Phase III clinical trial evaluating Neurodex(TM) for the treatment of patients with involuntary emotional expression disorder (IEED), also known as pseudobulbar affect and emotional lability, were published for the first time in the May issue of Annals of Neurology (Vol 59, Issue 5, 2006, pp 780-787). Data from this trial were previously presented at U.S. and international medical meetings in 2005. The published article "Randomized, Controlled Trial of Dextromethorphan/Quinidine for Pseudobulbar Affect in Multiple Sclerosis" describes the safety and efficacy of Neurodex, an orally administered combination of dextromethorphan and low dose quinidine, in the treatment of IEED patients with multiple sclerosis (MS).

IEED is a disorder that causes uncontrollable and unpredictable episodes of laughing and crying in patients with neurological disease or brain injury. The Phase III data showed that treatment with Neurodex decreased the frequency and severity of the patients' involuntary emotional episodes, the primary endpoint of the trial, as measured by the Center for Neurologic Lability Scale (CNS-LS), a validated instrument that assesses IEED episodes.

"Neurological disorders and brain injuries can affect patients' lives in devastating ways, but one consequence, IEED, is frequently overlooked or misdiagnosed," said Hillel Panitch, MD, Professor of Neurology at the University of Vermont College of Medicine and Director of the Multiple Sclerosis Center at Fletcher Allen Health Care in Burlington, Vermont, and the article's lead author. "IEED can be seriously disabling in social or occupational settings, adversely affecting the quality of life and quality of relationships of those suffering from this condition. The results of this study confirm earlier findings of the efficacy and safety of Neurodex. With no currently approved treatment, this represents an important step forward for patients suffering from IEED."

The double blind Phase III clinical study in MS patients with IEED was completed in June 2004. 150 patients at 22 clinical sites were randomized to receive either placebo or Neurodex on a 12-hour dosing schedule for 85 days. A minimum CNS-LS score of greater than or equal to 13 was required for inclusion in the study. For the primary endpoint, patients receiving Neurodex had a significantly greater reduction in CNS-LS score than those receiving placebo (p less than 0.0001) at all clinic visits (Days 15, 29, 57 and 85). All secondary endpoints also favored Neurodex, including the number of crying or laughing episodes (p less than or equal to 0.0077), quality of life (p less than 0.0001), quality of relationships (p=0.0001), and pain intensity score (p=0.0271).

The safety profile of Neurodex was favorable. The most common adverse events associated with Neurodex in this study were dizziness, nausea, fatigue, and headache.

About Involuntary Emotional Expression Disorder

Involuntary emotional expression disorder can occur when disease or injury damages the area of the brain that controls normal expression of emotion. This damage can disrupt brain signaling, causing a "short circuit," triggering episodes of involuntary emotional expression. IEED episodes can be unpredictable, exaggerated, and/or contrary to the patient's mood. Patients who experience unpredictable involuntary emotional displays are often anxious and embarrassed by them, and avoid social situations, which can result in isolation. It is hypothesized that the neurological diseases and injuries associated with IEED may lead to excessive signaling via glutamate, an excitatory neurotransmitter. Currently, there is no approved product indicated for the treatment of IEED which occurs in patients with neurological disorders including ALS, MS, Parkinson's disease, dementias including Alzheimer's disease, and brain injuries such as stroke and traumatic brain injury.

About Neurodex

Neurodex is a combination of two well-characterized compounds, the active ingredient dextromethorphan, and a low dose of the enzyme inhibitor quinidine, which serves to increase the bioavailability of dextromethorphan. The first-in-class drug candidate is believed to help regulate excitatory neurotransmission in two ways, through presynaptic inhibition of glutamate release via sigma-1 receptor agonist activity, and through postsynaptic glutamate response modulation via uncompetitive, low-affinity NMDA antagonist activity.

About AVANIR

AVANIR Pharmaceuticals is 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 diseases. AVANIR previously announced positive results in the second of two required Phase III clinical trials of Neurodex(TM), an investigational new drug for the treatment of involuntary emotional expression disorder currently under priority review with the FDA. Additionally, AVANIR has initiated a Phase III clinical trial for Neurodex as a potential treatment in patients with diabetic neuropathic pain, a second indication for Neurodex. AVANIR has active collaborations with two international pharmaceutical companies: Novartis International Pharmaceutical Ltd. for the treatment of inflammatory disease and AstraZeneca for the treatment of cardiovascular disease. 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.

Forward Looking Statement

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 Neurodex will receive regulatory approval; or that if such regulatory approval is received, 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.