Press Release

For Immediate Release

CORVALLIS, OR — July 29, 2009 — AVI BioPharma, Inc. (NASDAQ: AVII), a developer of RNA-based drugs, today announced that it will present at the Oligonucleotide Therapeutics -- From Concept to Implementation Conference, part of IBC Life Science's Drug Discovery Development Week, taking place Aug. 3-5, 2009 in Boston, MA.

Hong Moulton, Ph.D., Director of Discovery Research is invited to present on Monday, Aug. 3. Her talk "Peptide-Mediated Muscle Delivery of Morpholino Oligomers for Treatment of Duchenne Muscular Dystrophy" will feature an overview of the Company's peptide-conjugated morpholino oligomer (PPMO) technology for treatment of this disease.

Duchenne muscular dystrophy (DMD) is caused by mutations in the human dystrophin gene. The potential utility of PPMO chemistry for the systemic treatment of DMD has been demonstrated in mouse and non-human primate models. Preclinical studies have shown that the PPMO conjugates entered muscle cells, caused targeted exon-skipping, restored dystrophin, and reduced pathology and improved function of muscles. Results from a single dose escalation clinical study of AVI-4658, a PMO therapeutic, demonstrate that a single intramuscular (IM) showed that injection of the drug into a small foot muscle of several DMD patients successfully induced dystrophin production in each patient as compared to placebo treated muscle in the contralateral foot.

Drug Discovery & Development Week in Boston, MA includes five targeted scientific conferences featuring strategies and forward-looking approaches to help attendees accelerate small molecules, antibody therapeutics and oligonucleotide therapeutics from early discovery to the clinic.

About AVI BioPharma

AVI BioPharma is focused on the discovery and development of RNA-based drugs utilizing proprietary derivatives of its antisense chemistry (morpholino-modified phosphorodiamidate oligomers or PMOs) that can be applied to a wide range of diseases and genetic disorders through several distinct mechanisms of action. Unlike other RNA-based therapeutic approaches, AVI's antisense technology has been used to directly target both messenger RNA (mRNA) and its precursor (pre-mRNA), allowing for both up- and down-regulation of targeted genes and proteins. AVI's RNA-based drug programs are being evaluated for the treatment of Duchenne muscular dystrophy as well as for the treatment of cardiovascular restenosis through our partner Global Therapeutics, a Cook Group Company. AVI's antiviral programs have demonstrated promising outcomes in Ebola Zaire and Marburg Musoke virus infections and may prove applicable to other viral targets such as HCV or Dengue viruses. For more information, visit www.avibio.com.