Press Release

For Immediate Release

BOTHELL, WA — Aug. 27, 2009 — AVI BioPharma, Inc. (NASDAQ: AVII), a developer of RNA-based drugs, today announced that Hong Moulton, Ph.D., Director of Discovery Research, will give oral presentations highlighting improved analogues of AVI's phosphorodiamidate morpholino oligomer (PMO) chemistry at two upcoming scientific meetings.

At the 3rd Intracellular Delivery of Therapeutic Molecules: From Bench to Bedside, taking place in Montpellier, France, Dr. Moulton will give a presentation entitled "Targeted Gene Expression in vivo: Cell Penetrating Peptides Make Antisense Work" as part of the session on applications of delivery systems on Sept, 2, 2009. This conference, designed to bring together leading scientists in the field of cell-penetrating peptides and non viral delivery systems, is celebrating the 15 year anniversary of the discovery of cell-penetrating peptides.

At the Targeted Drug Delivery Conference, taking place in Lausanne, Switzerland, Dr. Mouton will present on "Cell Penetrating Peptidomorpholino Conjugates" on Sept. 3 as part of the peptide-bases delivery session.

Both presentations focus on AVI's next generation chemistry, peptide-conjugated PMO (PPMO), which improves delivery to nuclei of muscle cells and so is particularly applicable to drugs that work by exon skipping. With appropriate dosing, PPMO compounds restored dystrophin to nearly normal levels in skeletal and cardiac muscles in a mouse model of Duchenne muscular dystrophy without inducing toxicity or an immune response against the new dystrophin expressed. As a result, force generation and function of both skeletal and cardiac muscles were improved.

About AVI BioPharma

AVI BioPharma is focused on the discovery and development of RNA-based drugs utilizing proprietary derivatives of its antisense chemistry, (morpholino 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.