Antisense Research Identifies NEUGENE Compound's Success as a Potent Anti-Cancer Agent.

Business Editors, Health/Medical Writers

PORTLAND, Ore.--(BW HealthWire)--March 23, 2001

AVI BioPharma, Inc. (Nasdaq:AVII) (Nasdaq:AVIIW, AVIIZ) announced today that one of its gene-targeted therapies has been shown to be a potent anti-cancer agent in preclincal research in mice.

The company will present research findings on this potential therapy for cancer at the American Association of Cancer Research (AACR) annual meeting March 24-26 in New Orleans.

AVI already has human trials under way for its initial antisense (gene-based) therapy targeting cardiovascular restenosis. Those trials, and the cancer study that will be featured at AACR, are based on AVI's third-generation antisense platform technology known as NEUGENES(R).

John E. Mata, Ph.D., of AVI will present study findings showing that the Company's c-myc antisense morpholino oligomer compound AVI-4126, combined with standard chemotherapy, reduced or virtually eliminated, cancer growth in mice. AVI's Senior Vice President of Research and Development Patrick L. Iversen, Ph.D., a co-author on the study, stated "These findings are highly significant due to how representative this model system is in patients, and because the combination therapy was much more effective than either approach alone."

"We're encouraged by the continued success of this NEUGENE compound, and based on this data, we plan to initiate human clinical trials later this year," said Denis R. Burger, Ph.D., CEO of AVI. "In addition to our trials in cancer, which are the focus of our presentations at the AACR meeting, AVI also plans to study the compound in polycystic kidney disease. Further, we expect our NEUGENE gene-targeting technology to generate additional drug candidates each year for the foreseeable future."

Morpholino oligomers are third generation antisense agents that AVI scientists have used to block a variety of growth and cell cycle-related genes. The scientists found that oligomers directed against c-myc, a gene involved in cell proliferation disorders such as cancer and cardiovascular disease, were, when combined with chemotherapy, synergistic in halting cell growth.

More than 7,500 scientists from around the world are expected to attend the conference, which focuses on sharing significant developments in cancer research. In addition to its cancer model presentation, AVI will present research findings from two studies at the conference.

The American Association for Cancer Research is a scientific society of more than 15,000 laboratory and clinical cancer researchers. More information about the association or its annual meeting is available at http://www.aacr.org.

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, has completed enrollment in a Phase II trial in pancreatic cancer and is in a Phase III pivotal trial 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. More information about AVI is available on the Company's website 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.