AVI BioPharma Inc. Receives Additional Patent On Lead Product Candidate, Avicine.

PORTLAND, Ore.--(BW Healthwire)--Nov. 4, 1998--AVI BIOPHARMA INC. ("AVI")(Nasdaq:AVII, AVIIW) today announced it has been granted United States patent 5,817,753 for novel hCG specific peptides useful in preparing cancer vaccines to human chorionic gonadotropin (hCG).

This is the latest in a series of 11 U.S. patents licensed by AVI BioPharma from The Ohio State University covering the composition, manufacture and use of Avicine(tm) for treating and/or preventing cancer. This latest patent grant covers several novel hCG specific peptides that were modified to minimize potential cross reactivity to lutropin (hLH), a closely related pituitary hormone.

Avicine is prepared by conjugating highly specific hCG peptides to diphtheria toxoid and delivering them in a stable emulsion. Over 125 patients with advanced or metastatic cancer have been treated with Avicine. These preliminary studies have provided evidence of objective tumor responses and apparent survival benefits. The company is planning additional studies in colorectal, pancreatic and prostate cancer to evaluate efficacy in patients who have failed conventional therapy.

Denis R. Burger, Ph.D., President and Chief Executive Officer of AVI BioPharma, commented, "This latest patent provides protection for our newest formulations of Avicine. We are very pleased the U.S. patent office recognized the novel aspects of this invention. Combining the new hCG peptide with our existing hCG-CTP peptide will increase Avicine's ability to neutralize hCG by several fold. Given hCG's well-documented biological effect in cancer, we believe our new multivalent Avicine formulations hold great promise to improve survival benefits in cancer patients without significant toxicity."

Avicine, a therapeutic cancer vaccine, is AVI BioPharma's lead product candidate. Avicine elicits a highly specific immune response to the hormone and growth factor hCG, a cancer-associated oncofetal protein. Avicine is essentially a non-toxic immunotherapy and has been evaluated in five clinical trials. To date, more than 125 cancer patients have been treated. The preliminary studies have provided evidence of objective tumor responses and apparent survival benefits in patients who have failed conventional therapy.

AVI BioPharma Inc. is dedicated to the development and commercialization of products for the treatment of life-threatening diseases using three platform technologies: immunotherapy for cancer, gene-targeted drugs and intracellular drug delivery engines. Its lead clinical agent, Avicine(tm), an essentially non-toxic cancer vaccine, will soon 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 novel drug delivery technology, called CytoPorter(tm), that may be useful in significantly improving drug uptake while minimizing toxicity for a wide range of FDA approved drugs.

"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.