AVI BioPharma, Inc. Announces Data Presentation for RNA-Based Duchenne Muscular Dystrophy Drug Candidate at the 16th International World Muscle Society Congress

BOTHELL, WA--(Marketwire - October 18, 2011) - AVI BioPharma, Inc. (NASDAQ: AVII), a developer of RNA-based therapeutics, today announced data presentations for eteplirsen (the non-proprietary name assigned to AVI-4658), the Company’s investigational exon skipping therapy for the treatment of Duchenne muscular dystrophy, at the 16th International Congress of the World Muscle Society taking place Oct. 18-22, 2011 in Almancil, Algarve, Portugal.

Ed Kaye, MD, Senior Vice President and Chief Medical Officer at AVI, will present during the poster session Clinical Aspects on Oct. 19 at 2:00 p.m. Greenwich mean time +1/6:00 a.m. Pacific time. The presentation is titled “Comparative pharmacokinetics (PK) in primates and humans of AVI-4658, a Phosphorodiamidate Morpholino Oligomer (PMO) for treating DMD patients.”

Dr. Kaye’s presentation will be posted on the AVI BioPharma Web site in the “Events & Presentations” section after the session is completed.

About Eteplirsen

Eteplirsen (the nonproprietary name assigned to AVI-4658) is AVI’s lead drug candidate that is systemically delivered for the treatment of a substantial subgroup of patients with Duchenne muscular dystrophy (DMD). Data from clinical studies of eteplirsen in DMD patients have demonstrated a broadly favorable safety and tolerability profile and restoration of dystrophin protein expression.

Eteplirsen uses AVI’s novel phosphorodiamidate morpholino oligomer (PMO)-based chemistry and proprietary exon-skipping technology to skip exon 51 of the dystrophin gene. By skipping exon 51, eteplirsen may restore the gene’s ability to make a shorter, but still functional, form of dystrophin from mRNA. Promoting the synthesis of a truncated dystrophin protein is intended to improve, stabilize or significantly slow the disease process and prolong and improve the quality of life for patients with DMD.

AVI is also developing other PMO-based exon-skipping drug candidates intended to treat additional patients with DMD.

About AVI BioPharma

AVI BioPharma is focused on the discovery and development of novel RNA-based therapeutics for rare and infectious diseases, as well as other select disease targets. Applying pioneering technologies developed and optimized by AVI, the Company is able to target a broad range of diseases and disorders through distinct RNA-based mechanisms of action. Unlike other RNA-based approaches, AVI’s technologies can be used to directly target both messenger RNA (mRNA) and precursor messenger RNA (pre-mRNA) to either down-regulate (inhibit) or up-regulate (promote) the expression of targeted genes or proteins. By leveraging its highly differentiated RNA antisense-based technology platform, AVI has built a pipeline of potentially transformative therapeutic agents, including eteplirsen, which is in clinical development for the treatment of Duchenne muscular dystrophy, and multiple drug candidates that are in clinical development for the treatment of infectious diseases. For more information, visit www.avibio.com.

Forward-Looking Statements and Information

In order to provide AVI’s investors with an understanding of its current results and future prospects, this press release contains statements that are forward-looking. Any statements contained in this press release that are not statements of historical fact may be deemed to be forward-looking statements. Words such as “believes,” “anticipates,” “plans,” “expects,” “will,” “intends,” “potential,” “possible” and similar expressions are intended to identify forward-looking statements. These forward-looking statements include statements about the development of AVI’s product candidates, their efficacy, potency and utility in the treatment of rare and infectious diseases and their potential to treat a broad number of human diseases.

These forward-looking statements involve risks and uncertainties, many of which are beyond AVI’s control. Known risk factors include, among others: clinical trials may not demonstrate safety and efficacy of any of AVI’s drug candidates and/or AVI’s antisense-based technology platform; and any of AVI’s drug candidates may fail in development, may not receive required regulatory approvals, or be delayed to a point where they do not become commercially viable.

Any of the foregoing risks could materially and adversely affect AVI’s business, results of operations and the trading price of AVI’s common stock. For a detailed description of risks and uncertainties AVI faces, you are encouraged to review the official corporate documents filed with the Securities and Exchange Commission. AVI does not undertake any obligation to publicly update its forward-looking statements based on events or circumstances after the date hereof.