AVI BioPharma Inc. Presents Advantages of Resten-NG At the International Biotechnology Conference On Restenosis.

PORTLAND, Ore.--(BW HealthWire)--Sept. 24, 1998--AVI BIOPHARMA INC. ("AVI")(Nasdaq: AVII, AVIIW) today presented a research summary of Resten-NG, a product being developed for the prevention of restenosis, at the International Biotechnology Conference on Restenosis in Atlanta, Georgia. Restenosis is a frequent complication following treatment for coronary artery disease, during which damaged smooth muscle cells divide rapidly to cause closure of the artery for a second time. Resten-NG is AVI's gene-specific approach to halting cell division, based on an antisense mechanism of action.

Patrick L. Iversen, Ph.D., Vice President of Research and Development of AVI, who will be presenting at the conference, stated, "Preclinical research studies of Resten-NG confirm the fundamental advantages of the approach. Two years of cell culture studies have identified the optimal molecule with a demonstrable antisense mechanism of action. These results, combined with confirmation by three independent investigators, using three different animal species, form the basis of our fundamental confidence in Resten-NG. Furthermore, the disposition of the neutrally charged Resten-NG at the site of balloon angioplasty from systemic circulation provides another significant advantage of uncomplicated delivery and thus a more simple therapeutic regimen."

Collaborative preclinical studies have demonstrated efficacy in three different animal models at Columbia University, the University of Nebraska Medical Center, and the Medical College of Wisconsin. With this progress, AVI has initiated the manufacture of Resten-NG for impending clinical trials. Dwight D. Weller, Ph.D. and Senior Vice President of Chemistry and Manufacturing at AVI, noted, "We have successfully completed a process for the scale-up synthesis of high quality and high purity oligomers. The scale is now sufficient for 10 gram batches of GMP material, which is more than adequate for upcoming toxicity studies and Phase I clinical studies." Denis R. Burger, Ph.D., President and Chief Executive Officer of AVI, commented, "We are very pleased with the efficacy data received thus far and are in the process of compiling our Investigational New Drug (IND) application for the FDA."

AVI BioPharma Inc. is dedicated to the development and commercialization of products for the treatment of life-threatening diseases using three platform technologies: vaccines, gene-targeted drugs, and drug delivery. Its lead product candidate, Avicine(TM), an essentially non-toxic cancer vaccine, is about to enter a Phase III licensing trial in colorectal cancer, a Phase II/III trial in pancreatic cancer and a Phase II trial in prostate cancer. The company has also developed a patented class of gene-targeted drugs, called NEUGENES(R), which may be useful in the treatment of a wide range of human diseases including cardiovascular restenosis and cancer. Further, AVI has developed a drug delivery technology, called CYTOPORTER(TM), which has been successful in penetrating cell membranes and, as a result, may be useful in improving delivery of many FDA-approved drugs and drugs in development.

"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 pre-clinical 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.