GeoVax Labs, Inc. (OTC Bulletin Board: GOVX) (the "Company"), an Atlanta-based, biopharmaceutical company developing vaccines for diseases caused by HIV-1 (Human Immunodeficiency Virus), today announced that it presented the results of a preclinical study on a prototype HIV/AIDS vaccine at the Conference on Retroviruses and Opportunistic Infections (CROI) in San Francisco.
The oral presentation, "Preclinical Studies on DNA/MVA Vaccines: Co-expressed GM-CSF, a Strong Adjuvant for Prevention of Infection," was presented by Dr. Harriet Robinson, Chief Scientific Officer for GeoVax and developer of the Company's vaccines. The study investigated the use of GM-CSF (granulocyte/macrophage colony-stimulating factor) as an adjuvant with the DNA prime for the GeoVax DNA/MVA vaccine for prevention of HIV/AIDS.
Adjuvants are agents that can increase the potency and effectiveness of a vaccine. GeoVax's work on adjuvants started in 2007. At that time, the National Institutes of Health (NIH) granted the company $15 million over five years to fund the search for any benefit derived from the use of adjuvants. Results using GM-CSF showed protection from infection from simian immunodeficiency virus (SIV-monkey version of the HIV virus) in 70% of the seven exposed animals after 12 weekly exposures to the SIV virus.
"This is the highest level for prevention of an immunodeficiency virus infection ever reported in a non-human primate model," said Dr. Robinson. "We and other scientists originally thought it very difficult, even impossible, to completely prevent SIV infections. But based on the results from this study, we are now hopeful that our DNA/MVA vaccine supplemented with GM-CSF could actually prevent, not just control, HIV infections in humans."
The GM-CSF results were produced in a study using repeated rectal challenges with a dose of SIV that is 40 to 400 times the estimated typical dose of HIV associated with infections in humans. Following 12 weekly infection attempts, all nine of the unvaccinated animals became infected, whereas only two of the seven animals vaccinated with the adjuvant-supplemented vaccine became infected.
"An ideal vaccine does not need an adjuvant and our vaccine currently in Phase 2a testing for prevention of HIV/AIDS does not contain one. However, with this recent success, we believe we have the data needed to support the design of an alternative HIV vaccine for GeoVax's product pipeline if our current vaccine does not provide good success," added Dr. Robinson.
GeoVax's mission is to develop both a preventative and therapeutic vaccine to combat HIV/AIDS. Robert McNally, Ph.D., President and Chief Executive Officer, explained, "We are currently in a Phase 2a clinical trial with a vaccine that proved safe and immunogenic in Phase 1 testing. We are and continue to be optimistic about this product. The results from the adjuvant-supplemented product test suggest that we may have an effective alternative product should our non-adjuvanted vaccine prove suboptimal in expanded human clinical trials. This vaccine is being added to the patent portfolio of the company."
The work identifying the adjuvant activity of GM-CSF is supported by an NIH funded Integrated Preclinical/Clinical AIDS Vaccine Development program. Animal studies were completed at the Yerkes Primate Research Center in close collaboration with Drs. Lilin Lai and Rama Rao Amara. Investigators at Louisiana State University and Duke University also participated in the project.