AVANIR Pharmaceuticals Announces the Complete Enrollment of the Zenvia Open Label Extension Study

Topline Data from Double-Blind Phase of STAR Trial Expected in August

ALISO VIEJO, Calif., July 6, 2009 - AVANIR Pharmaceuticals, Inc. (NASDAQ: AVNR) today announced that the open label extension of the confirmatory Phase III STAR trial is now fully enrolled. The primary objective of the open-label extension study is to assess the long-term safety of Zenvia™ (dextromethorphan/quinidine [DM/Q]) in patients diagnosed with pseudobulbar affect (PBA) resulting from an underlying neurological disorder. In total, 282 of 326 patients (or 86.5%) completed the 12-week double-blind phase of the study and were eligible to enroll in the open label extension phase. A total of 253 (or 89.7%) of eligible patients elected to enroll in the 12-week open label safety extension. The low overall rate of discontinuation in the blinded phase and high percentage of eligible patients choosing to enroll in the optional open label extension phase compare favorably with previous experience.

"Completion of the blinded phase and full enrollment of the open label phase of the STAR trial are important milestones for AVANIR," said Dr. Randall Kaye, AVANIR's Chief Medical Officer. "We look forward to unblinding the top-line data in August 2009 and expect to have data from the open label extension available by the end of the year. With the complete data set from the STAR trial in hand, we plan to submit our full response to the approvable letter in the first half of 2010."

ABOUT THE STAR TRIAL

The STAR (Safety, Tolerability and Efficacy Results of AVP-923 in PBA) trial is a confirmatory Phase III trial of Zenvia in patients with PBA resulting from an underlying neurological disorder. The randomized, multi-center, international STAR trial compares active treatment with Zenvia 30/10 mg (DM/Q) and Zenvia 20/10 mg (DM/Q) to placebo during a 12-week double-blinded phase, followed by a 12-week, open-label safety extension phase. The STAR trial had a targeted enrollment of 126 patients with multiple sclerosis (MS) and 180 patients with amyotrophic lateral sclerosis (ALS) who exhibit signs and symptoms of PBA at approximately 60 sites in the U.S. and Latin America. At the conclusion of enrollment, AVANIR had enrolled a total of 326 patients (129 with underlying MS and 197 with underlying ALS). The primary efficacy analysis is based on the changes in crying/laughing episode rates recorded in patient diaries. Secondary endpoints for this clinical trial include: 1) Center for Neurologic Study-Lability Scale (CNS-LS) score; 2) Neuropsychiatric Inventory Questionnaire (NPI-Q); 3) SF-36 Health Survey; 4) Beck Depression Inventory (BDI-II); and 5) Pain Rating Scale score (MS patients only). Safety and tolerability of Zenvia are determined by reporting adverse events, physical exam, vital signs, electrocardiogram, respiratory function tests and clinical assessment of clinical laboratory variables. The STAR trial is being conducted under a Special Protocol Assessment (SPA) from the U.S. Food and Drug Administration (FDA). For more information visit www.pbatrial.com.

ABOUT ZENVIA

Zenvia is a combination of two well-characterized compounds: the therapeutically active ingredient dextromethorphan and the enzyme inhibitor quinidine, which serves to increase the bioavailability of dextromethorphan. This first-in-class drug candidate is believed to help regulate excitatory neurotransmission in two ways: through pre-synaptic inhibition of glutamate release via sigma-1 receptor agonist activity and through postsynaptic glutamate response modulation via uncompetitive, low-affinity NMDA antagonist activity. Zenvia is currently in development for the treatment of PBA and diabetic peripheral neuropathic (DPN) pain. In October 2006, the Company received an approvable letter for Zenvia in the treatment of PBA. The Company has initiated a confirmatory Phase III study under a Special Protocol Assessment (SPA) agreement with the FDA utilizing a new lower quinidine dose formulation of Zenvia intended to address safety concerns raised in the Agency's approvable letter. For more information about this trial visit http://www.pbatrial.com, and for more information about the Agency's SPA process, see http://www.fda.gov/cder/guidance/3764fnl.htm. In April 2007, AVANIR announced successfully meeting all primary endpoints in a Phase III study of Zenvia in DPN pain. In May 2008, the Company released top-line results of a formal PK study that identified alternative lower-dose quinidine formulations of Zenvia for DPN pain intended to deliver similar efficacy and improved safety/tolerability versus the formulations previously tested for this indication. AVANIR is now engaged in discussions with the FDA under the SPA process regarding the design of the next Phase III study in DPN pain and overall program requirements.

ABOUT AVANIR

AVANIR Pharmaceuticals, Inc. is focused on acquiring, developing, and commercializing novel therapeutic products for the treatment of chronic diseases. AVANIR's products and product candidates address therapeutic markets that include the central nervous system, inflammation, and infectious diseases. AVANIR's lead product candidate, Zenvia, is being developed for the treatment of PBA and DPN pain. AVANIR has licensed its MIF inhibitor program to Novartis International Pharmaceuticals Ltd. and has sold its anthrax monoclonal antibody program to Emergent BioSolutions. The Company's first commercialized product, Abreva®, 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 and further information about pseudobulbar affect can be found at www.PBAinfo.org.

FORWARD-LOOKING STATEMENTS

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," "intend," "anticipate," "believe," "plan," "goal," "expect," "project," 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. For example, there can be no assurance that the Company will successfully meet projected timelines, that any new doses of Zenvia for PBA or DPN pain will be safe and effective, or that the U.S. Food and Drug Administration (FDA) will approve Zenvia for any indication. Risks and uncertainties affecting the Company's financial condition and operations 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 to update these forward-looking statements.

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AVANIR Investor Contacts
Eric Benevich
Brenna Mullen
ir@avanir.com
949-389-6700

Jul 06, 2009