AVANIR Pharmaceuticals Announces Positive Results of Phase II/III Clinical Trial of Neurodex for Emotional Lability

SAN DIEGO, Jun 20, 2002 /PRNewswire-FirstCall via COMTEX/ --

Study Achieved Statistical Significance in Primary Efficacy Factor

AVANIR Pharmaceuticals (Amex: AVN) announced the results of a Phase II/III clinical trial investigating the safety and effectiveness of Neurodex in the treatment of pseudobulbar affect (also known as emotional lability, or pathological laughing or crying) in subjects with amyotrophic lateral sclerosis (ALS). The double blind, controlled, multicenter clinical trial had three treatment arms that compared Neurodex to each of its two active components, dextromethorphan and an enzyme inhibitor.

The primary efficacy variable for the study was change from baseline in a subject's score on the CNS-Lability Scale (CNS-LS). The CNS-LS is a validated, published scale that measures the severity and frequency of a subject's episodes of pathological laughing and/or crying. This endpoint of the study in the intent-to-treat population was statistically significant (p less than or equal to 0.0042) in favor of Neurodex when compared to either of the other two treatment arms. Secondary efficacy endpoints and other aspects of the study are being evaluated and will be reported at a later date.

"The results of this trial are very encouraging and validate the Company's decision to quickly advance this important drug candidate into a Phase II/III clinical trial," said AVANIR President and Chief Executive Officer Gerald J. Yakatan, Ph.D. "The successful outcome of the trial further demonstrates AVANIR's core strengths of drug discovery and development and our ability to design and execute effective clinical trials."

Emotional lability is a symptom experienced by an estimated one million patients with various neurological conditions including ALS, Alzheimer's disease, multiple sclerosis (MS), stroke and traumatic brain injury (TBI). Neurodex is the first drug candidate in clinical development specifically intended to treat emotional lability.

Neurodex is a patented, orally administered combination of dextromethorphan and an enzyme inhibitor. The enzyme inhibitor allows for sustained, elevated levels of dextromethorphan in the body. In this Phase II/III study of Neurodex, subjects were treated twice a day on a 12-hour dosing schedule.

"The data from this study are robust and favor Neurodex over the other treatment arms," said James E. Berg, AVANIR's Vice President of Clinical and Regulatory Affairs. "This trial was conducted by leading clinical investigators in ALS research and treatment. Their dedication to this first ever multicenter study of pseudobulbar affect may one day result in an approved treatment for this distressing symptom."

Pseudobulbar affect is a phenomenon that causes laughing and crying not necessarily associated with emotion. Neurodegenerative diseases such as ALS, Alzheimer's disease and MS involve the loss of control of upper motor neurons which control the lower motor neurons. The term pseudobulbar palsy is used to describe uncontrolled activity of the lower motor neurons of the bulbar (brainstem) region that results in episodes of uncontrolled laughing and crying that can be both embarrassing and frightening to patients and their caregivers.

"Positive clinical data from this initial clinical trial of Neurodex provides us with the scientific rationale to move forward with its clinical development in other disease states and conditions," continued Dr. Yakatan. "We will initiate a second pivotal clinical trial of Neurodex in MS patients suffering from pseudobulbar affect later this year. An open label trial of Neurodex in patients with pseudobulbar affect is also planned for later this year. Additionally, we intend to initiate an open label, dose-ranging Phase II study examining Neurodex in the treatment of diabetic neuropathic pain this year."

Management will host a conference call with a simultaneous webcast on June 20, 2002, at 1:15 p.m. Pacific/ 4:15 p.m. Eastern Time, to discuss today's press release. The call/webcast will feature President and Chief Executive Officer Gerald J. Yakatan, Ph.D., Vice President of Clinical and Regulatory Affairs James E. Berg, and Vice President and Chief Financial Officer Gregory Hanson. The webcast will be available live via the Internet by accessing AVANIR's web site at www.avanir.com or CCBN's www.companyboardroom.com . Please go to either web site at least ten minutes early to register, download and install any necessary audio software. Replays of the webcast will be available for 90 days, and a phone replay will be available through June 27, 2002, by dialing 888-266-2086 or 703-925-2435 and entering the passcode 6068300.

AVANIR Pharmaceuticals, based in San Diego, is a biopharmaceutical drug discovery and development company with an FDA-approved product. AVANIR is engaged in research, discovery, development and licensing of innovative drug products and, through its subsidiary Xenerex Biosciences, antibody generation services. AVANIR has the exclusive license to develop, manufacture and market Neurodex for four potential indications: emotional lability, neuropathic pain, chronic cough and weaning drug-dependent patients from narcotics and anti-depressants. Neurodex is protected by six issued U.S. patents. The Company's website is http://www.avanir.com .

AVANIR press releases and presentations, including any forward-looking statements contained therein, 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 as "estimate," "anticipate," "intend," "plan" or "expect." Research findings are not always supportable by evidence obtained from subsequent clinical trials and the Company can make no assurances that the Neurodex clinical trials will yield positive results. 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.

For further information, please contact: General Information, Gregg Sloate, +1-310-407-6547, gsloate@webershandwick.com, or Analyst/Investor, Tricia Ross, +1-310-407-6540, tross@webershandwick.com, or Media, Tim Grace, +1-312-640-6667, tgrace@webershandwick.com, all of FRB|Weber Shandwick, for AVANIR Pharmaceuticals; or Patrice Saxon, Investor Relations of AVANIR Pharmaceuticals, +1-858-622-5202, psaxon@avanir.com

SOURCE AVANIR Pharmaceuticals

CONTACT:
General Information, Gregg Sloate, +1-310-407-6547,
gsloate@webershandwick.com, or Analyst/Investor, Tricia Ross, +1-310-407-6540,
tross@webershandwick.com, or Media, Tim Grace, +1-312-640-6667,
tgrace@webershandwick.com, all of FRB|Weber Shandwick, for AVANIR
Pharmaceuticals; or Patrice Saxon, Investor Relations of AVANIR
Pharmaceuticals, +1-858-622-5202, psaxon@avanir.com

URL:
http://www.avanir.com
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