AVI BioPharma to Present Novel Antisense Approach at Leading Interventional Cardiology Conference

Resten-NG Shows Superior Properties for Preventing Coronary Occlusion Following Angiography and Stent Placement

PORTLAND, Ore. - May 17, 2002 - AVI BioPharma, Inc. (Nasdaq: AVII, AVIIW, AVIIZ), today announced that Denis R. Burger, Ph.D., AVI's chief executive officer, and AVI scientist, Derek Knapp will present data showing the efficacy of AVI's third-generation antisense drug, Resten-NG™, in preventing coronary restenosis, at the 25th annual conference of The Society for Cardiac Angiography and Interventions in Seattle.

On May 17 from 8:30-10:30 a.m. Mr. Knapp will present: "Local delivery of a third generation c-myc antisense: Concept, experimental results and future directions." Results of the study demonstrate that Resten-NG is highly effective in the inhibition of coronary artery smooth muscle cell growth and preservation of vascular endothelial cells, thus promoting the repair of vascular injury caused by angioplasty procedures. These favorable properties were not observed for rapamycin or paclitaxel, which also are being evaluated by interventional cardiologists.

At a concurrent session on May 17 from 3:30-5 p.m. Dr. Burger will discuss the application of AVI's antisense technology for coated stents. "AVI is very pleased to be sharing the stage with leading members of the cardiology community," Dr. Burger said. "Coronary artery disease is a key clinical development area for AVI as evidenced by its late-stage clinical program for coated stents with Medtronic, Inc. In addition, late last month we announced the initiation of a clinical development program with Thomas Jefferson University in Philadelphia using Resten-NG to reduce the failure rate of coronary artery bypass grafts."

About Resten-NG:
Resten-NG is a NeuGene® compound for treating cardiovascular restenosis, or the renarrowing of an artery following balloon angioplasty. Resten-NG targets a transcription factor, and upon entering arterial cells, it blocks the underlying cause of the disease: smooth muscle cell activation and proliferation. AVI has demonstrated in preclinical studies that Resten-NG significantly reduced coronary restenosis. A global license has been granted to Medtronic for AVI's antisense compounds deployed on stents or other devices for treating restenosis. AVI is currently in a Phase II trial with this product.

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 is initiating 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. It is currently in Phase II trials for restenosis and in Phase I/II trials for cancer and polycystic kidney disease. AVI has recently completed a Phase I NeuGene antisense study that successfully down-regulated the liver enzyme Cytochrome P450 and modified drug metabolism. More information about AVI is available on the Company's Web site at http://www.avibio.com/.

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