AVANIR Pharmaceuticals Licenses Anthrax Monoclonal Antibody Program to Emergent BioSolutions

ALISO VIEJO, Calif., March 6, 2008 - AVANIR Pharmaceuticals (NASDAQ:AVNR) today announced that it has executed a definitive agreement to sell its portfolio of human monoclonal anthrax antibodies to Emergent BioSolutions (NYSE:EBS). As part of the transaction, Emergent acquired AVANIR's lead candidate (AVP-21D9) along with several additional anthrax antibodies. In addition, Emergent also received a limited exclusive license to use AVANIR's proprietary Xenerex Technology platform to develop future human monoclonal antibodies targeted against Bacillus anthracis. Under terms of the definitive agreement, AVANIR has the potential to receive up to $1.75 million in upfront and milestone payments, as well as royalties on annual net sales if the product is commercialized.

"Emergent is a proven leader in the area of Biodefense with significant experience in the anthrax field," said Greg Flesher, Vice President of Business Development for AVANIR Pharmaceuticals. "They have a track record of successfully acquiring development-stage biologics, as well as securing and delivering on significant procurement contracts from the U.S. Government. This transaction places AVP-21D9 in very capable hands."

AVP-21D9 is a fully human monoclonal antibody developed using the Xenerex Technology platform. Data published in Infection and Immunity[75(7): 3414-3424, 2007] demonstrate that the antibody is effective in protection of animals challenged with lethal doses of inhaled anthrax spores and reduces the dissemination of Bacillus anthracis in infected animals. To date, AVP-21D9 has been funded primarily through grants from the NIH/NIAID.

"We are pleased to partner this program with Emergent BioSolutions. This transaction, along with other potential monetization of non-core assets, will provide additional non-dilutive financing and allow us to continue our focus on the ongoing clinical development of our promising Phase III drug candidate Zenvia (dextromethorphan/quinidine)," said Keith Katkin, AVANIR's President and CEO.

About AVANIR

AVANIR Pharmaceuticals 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 pseudobulbar affect (PBA) and is the subject of an approvable letter from the U.S. Food and Drug Administration (FDA) for that indication. 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 Zenvia in the treatment of PBA. Additionally, in April 2007 AVANIR announced meeting all primary endpoints in a Phase III clinical trial with Zenvia in patients with diabetic peripheral neuropathic (DPN) pain. The Company is conducting a formal pharmacokinetic (PK) study to assess alternative lower-dose quinidine formulations of Zenvia for DPN pain that are intended to deliver similar efficacy and improve safety/tolerability versus the formulations previously tested for this indication. AVANIR has licensed the 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.

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," 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 the Company will receive the full amounts potentially available under the sale to Emergent or that Emergent will succeed in developing the AVANIR anthrax antibodies. There can also be no assurance that any additional Phase III trial for Zenvia will be successful, that any new doses of Zenvia 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

Mar 06, 2008