Gerald Zon Joins AVI BioPharma Scientific Advisory Board

Antisense Pioneer Brings More Than 30 Years of Experience to AVI

PORTLAND, Ore. - June 23, 2003 - AVI BioPharma, Inc. (Nasdaq: AVII, AVIIW, AVIIZ), today announced the addition of Gerald Zon, Ph.D., to AVI's scientific advisory board. Dr. Zon is the primary inventor of the most widely used antisense agents today. As a result of his contributions to the genesis of antisense therapeutics, Dr. Zon has a fundamental understanding of the opportunities and challenges facing antisense drug development today.

"We are honored that Dr. Zon has joined our efforts to continue development of AVI's proprietary antisense compounds, NeuGenes®," said Patrick L. Iversen, Ph.D., senior vice president of research and development at AVI. "I have known and worked with Dr. Zon since 1987 and look forward to his insightful contributions to the scientific directions of AVI BioPharma. The depth and breadth of Dr. Zon's experience is unmatched in the antisense field."

"I'm pleased to have been asked to join AVI's scientific advisory board," said Dr. Zon. "Having worked in the antisense field for many years, I have seen AVI's antisense program develop from original concept to today's third-generation NeuGene drugs, and I'm impressed with the progress they've made."

Following receipt of his Ph.D. in organic chemistry from Princeton University, Dr. Zon worked in academia for 10 years. His early antisense research focused on drugs to target the human immunodeficiency virus 1 (HIV-1). Dr. Zon joined the U.S. Food and Drug Administration in 1981, where he served as chief of the Molecular Pharmacology Laboratory, which evaluated both classical drugs and biological products.

Upon joining Applied Biosystems in 1987, Dr. Zon implemented worldwide commercialization of automated research-scale oligonucleotide synthesis and purification protocols. Dr. Zon also was responsible for identifying and proposing substantial new business opportunities involving nucleic acid-based drugs. In 1992, Dr. Zon co-founded and served as vice president of Medicinal Chemistry for Lynx Therapeutics, Inc., a company devoted to antisense therapeutics. Most recently, Dr. Zon served as senior director of Research and Development for Genetic Analysis, New and Other Platforms involving Applied Biosystems products.

Dr. Zon has co-authored several investigational new drug (IND) applications related to antisense drugs for clinical studies of acute myelogenous leukemia (AML), chronic myelogenous leukemia (CML) and coronary restenosis following balloon angioplasty.

About AVI BioPharma

AVI BioPharma develops therapeutic products for the treatment of life-threatening diseases using two technology platforms: NeuGene antisense drugs and cancer immunotherapy. Its lead cancer agent, AVICINE®, a therapeutic cancer vaccine, has completed three Phase II trials in colorectal and pancreatic cancer, and the company plans to initiate a Phase III pivotal trial in pancreatic cancer, with a supporting study in colorectal cancer. The first application of its NeuGene compounds, Resten-NG™, is designed to treat cancer, cardiovascular restenosis and other cell proliferation disorders by inhibiting the production of a cellular transcription factor, the oncogene c-myc. The company is currently in a Phase II trial for restenosis. AVI has completed four Phase I NeuGene antisense studies that successfully down-regulated the liver enzyme cytochrome P-450 and modified drug metabolism, a Phase Ib trial in polycystic kidney disease, and a Phase Ib trial in cancer. More information about AVI is available on the Company's Web site at http://www.avibio.com/.

"Safe Harbor" Statement under the Private Securities Litigation Reform Act of 1995: The statements that are not historical facts contained in this release are forward-looking statements that involve risks and uncertainties, including, but not limited to, the results of research and development efforts, the results of preclinical and clinical testing, the effect of regulation by the FDA and other agencies, the impact of competitive products, product development, commercialization and technological difficulties, and other risks detailed in the Company's Securities and Exchange Commission filings.