Press Release

Cell-Culture Research Targets HIV-1 Vif and Tar Stem Loop

PORTLAND, Ore.--(BUSINESS WIRE)--March 1, 2007--AVI BioPharma, Inc. (Nasdaq:AVII), presented research results titled "Morpholino Antisense Oligomers that Target the Lentiviral Vif Gene and Tar Stem Loop are Novel Antiretroviral Drug Candidates" at the 14th Annual Conference on Retroviruses and Opportunistic Infections (CROI), held this week in Los Angeles. Richard K. Bestwick, Ph.D., director of antiretroviral research for AVI, presented the results in poster form.

Dr. Bestwick reported on AVI's investigations into the feasibility of novel antiviral targets: the HIV-1 viral infectivity factor (Vif) and the HIV-1 transactivation response element (Tar) stem loop. These targets are considered integral to viral replication and protein expression, respectively. The viral genome target sites were selected in part due to their presence in all known viral isolates. The antiviral potential of these targets was evaluated with AVI compounds in test tube (in vitro translation) and cell-culture studies. The studies suggested that the targets are promising candidates for further investigation in more sophisticated cell-culture systems and in animal models.

"New approaches to antiviral therapy for HIV-1 are needed," said Patrick L. Iversen, Ph.D., senior vice president of research and development at AVI BioPharma. "These studies add to our growing understanding of antisense approaches to treat viral infections, specifically HIV-1, which represents one of the most challenging areas for antiviral therapy."

About AVI BioPharma

AVI BioPharma develops therapeutic products for the treatment of life-threatening diseases using third-generation NEUGENE antisense drugs. AVI's lead NEUGENE antisense compound is designed to target cell proliferation disorders, including cardiovascular restenosis, cancer and polycystic kidney disease. In addition to targeting specific genes in the body, AVI's antiviral program uses NEUGENE antisense compounds to combat disease by targeting single-stranded RNA viruses, including West Nile virus, hepatitis C virus, dengue virus, Ebola virus and influenza A virus. AVI has introduced a NEUGENE-based exon-skipping technology called ESPRIT therapy. More information about AVI is available on the company's Web site 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 preclinical 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.

    CONTACT: AVI Contact:
             AVI BioPharma, Inc.
             Michael Hubbard, hubbard@avibio.com
             503-227-0554
             or
             Investor Contacts:
             Lippert/Heilshorn & Associates Inc.
             Jody Cain, jcain@lhai.com
             Brandi Floberg, bfloberg@lhai.com
             310-691-7100
             or
             Press Contact:
             Waggener Edstrom Worldwide
             Bioscience and Healthcare Practice
             Jenny Moede, jmoede@waggeneredstrom.com
             503-443-7000

    SOURCE: AVI BioPharma, Inc.