AVI BioPharma and Interventional Technologies Initiate Collaboration for Human Clinical Trials in Cardiovascular Restenosis.

Business Editors, Health/Medical Writers

PORTLAND, Ore.--(BW HealthWire)--March 10, 2000

AVI's Novel NEUGENE(R) Drug, Resten-NG, Will be

Used in Combination With IVT's Drug Delivery Catheter

to Treat Restenosis in Upcoming Phase II Studies.

AVI BioPharma (Nasdaq:AVII)(Nasdaq:AVIIW)(Nasdaq:AVIIZ) and Interventional Technologies (IVT) today announced they have initiated a collaboration in human clinical trials of Resten-NG(TM), AVI's gene-targeted therapeutic drug for cardiovascular restenosis.

Under terms of collaboration IVT will supply their Infiltrator(R) intramural delivery catheters for the upcoming Phase II trials at New York's Lenox Hill Hospital, and AVI will use this catheter in its Resten-NG development program.

Resten-NG will be delivered into the coronary arteries of patients undergoing balloon angioplasty. The Infiltrator has proven to be remarkably effective in delivery of Resten-NG in preclinical studies conducted by AVI. These studies also indicated that Resten-NG was considerably more potent and less toxic than other antisense agents in clinical development.

Full results from these studies will be presented at the American College of Cardiology Annual Meeting March 11-16 in Anaheim, California. Phase I human trials with Resten-NG are currently in progress. Resten-NG is AVI's first compound from its novel third generation NEUGENE(R) antisense technology platform to enter clinical trials.

"We were pleased to have identified an exceptional delivery catheter for Resten-NG to support our upcoming Phase II trials," Denis R. Burger, Ph.D., President and Chief Executive Officer of AVI said. "We believe that the introduction of Resten-NG into the clinic in conjunction with use of the Infiltrator will demonstrate that our proprietary NEUGENE antisense will fulfill the promise that other antisense technologies have thus far failed to meet."

Dr. Burger continued, "After years of comprehensive research, we have developed an antisense chemistry that overcomes the pharmaceutical limitations still inherent in other antisense approaches, positioning AVI as a leader in this field. Because NEUGENE compounds were designed and synthesized with novel chemistries, they have pharmaceutical advantages not possible with other antisense technologies."

Commenting on the collaboration, Robert E. Reiss, Interventional Technologies Chairman and Chief Executive Officer, said, "We are very pleased to be working with AVI and the world class researchers associated with this project. Precise volumetric deposition directly into the arterial wall will maximize Resten-NG's therapeutic benefits while demonstrating the Infiltrator's fast and efficient intramural delivery."

The Infiltrator has been registered with the U.S. FDA as a Device Master File and has been awarded the CE Mark for European distribution.

Resten-NG targets the genetic sequence c-myc, a gene responsible for initiating cell replication. Extensive preclinical studies of the compound in treating restenosis have shown highly significant preservation of vessel passageways and prevention of arterial wall thickening. Delivering Resten-NG to the site of angioplasty blocks the growth and proliferation events in the vessel walls. Approximately 1.2 million balloon angioplasty procedures are performed each year with a market exceeding $1 billion annually.

Interventional Technologies is a leader in developing engineering solutions for treating cardiovascular diseases. Its lead product, the Cutting Balloon(TM) microsurgical dilatation system, is utilized around the world and currently awaits FDA approval. The company also markets the TEC(R) Thrombectomy System to remove plaque and thrombus (blood clots) from diseased arteries and the Trackwire(R) family of guidewires. Other products in development include the LP-Stent(TM), which carries the CE Mark and is undergoing US Clinical Trials, The Irradiator(TM) radiopharmaceutical delivery system, the Fullflow(R) non-balloon perfusion dilatation system, a precious-metal alloy stent for saphenous vein bypass grafts and a covered stent. The company's facilities are located in San Diego and Murrieta, California, as well as Letterkenny, Ireland.

AVI BioPharma develops therapeutic products for the treatment of life-threatening diseases using two technology platforms: cancer immunotherapy and gene-targeted drugs. Its lead clinical agent, AVICINE(TM), a therapeutic cancer vaccine, is undergoing a Phase II trial in pancreatic cancer, and will soon enter a Phase III pivotal trial in colorectal cancer and a Phase II trial in prostate 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 I trials for restenosis. More information about AVI is available 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 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.