AVI BioPharma Presents Additional Data on West Nile Virus Clinical Trial At International Antiviral Conference
First Report of an Antisense Drug Crossing the Blood-Brain Barrier
PORTLAND, Ore. - May 4, 2004 - AVI BioPharma, Inc. (Nasdaq: AVII), today announced that data from its Phase I/II West Nile virus (WNV) clinical trial with its proprietary NeuGene® antisense drug AVI-4020 showed presence of the drug in cerebrospinal fluid (CSF) of patients treated with AVI-4020. This represents the first report of an antisense drug crossing the blood-brain barrier in a clinical study. The data were presented at the 17th International Conference on Antiviral Research by Patrick L. Iversen, Ph.D., senior vice president of research and development at AVI.
The Phase I/II West Nile virus clinical study was conducted in fall 2003, enrolling 10 patients, nine of whom received AVI-4020 and one of whom received a placebo. The trial was conducted in Colorado at the Boulder Community Medical Center, and was designed to evaluate the safety of AVI-4020. As previously reported by AVI, the study met its primary endpoint, as no safety concerns pertaining to the drug were identified during the trial.
Pharmacokinetic (PK) data from the study showed that the plasma elimination half-life of this third-generation antisense drug was four to five hours. Approximately 24 hours after the last dose of the drug was administered, a spinal tap was done to collect CSF for PK analysis. When the CSF samples were analyzed, all of the patients who received the drug intravenously had drug in the CSF. The mean concentration of the antisense drug was 8.1 nanograms per milliliter (ng/ml) or approximately 1 nanoMolar (nM).
"In addition to the safety results seen in this study, we now have the first evidence of an antisense drug crossing the blood-brain barrier as measured by concentrations in the cerebrospinal fluid of treated patients," Iversen said. "These results open up numerous avenues for development of our NeuGene compounds in neurological indications, and we plan on further exploring this significant potential in diseases with neurological implications."
"AVI-4020 is a unique drug with the potential to treat West Nile virus, a disease with no existing treatment options," said Nelson Gantz, M.D., chief of Infectious Diseases at the Boulder Community Hospital and an investigator in the study. "In this initial small study, the compound was well tolerated, with no reported drug-related serious adverse events. The results presented show the drug can enter the central nervous system, which appears consistent with the improvement noted in the condition of the patients, and which is an important element in treating viruses, such as West Nile, that may cause brain inflammation. Based on the results to date and the need for new treatments against emerging viruses such as West Nile, AVI-4020 merits further study."
About AVI BioPharma
AVI BioPharma develops therapeutic products for the treatment of life-threatening diseases using two technology platforms: third-generation NeuGene antisense drugs and cancer immunotherapy. 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 target single-stranded RNA viruses, including West Nile virus, SARS coronavirus, calicivirus and hepatitis C. AVI's second technology, Avicine®, is a therapeutic cancer vaccine with late-stage trials planned for the treatment of pancreatic cancer. 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.