Booster Vaccination After ~7 Years Resulted in 600-fold Increase in Antibody Response
ATLANTA, GA, Oct. 24, 2018 (GLOBE NEWSWIRE) -- via NEWMEDIAWIRE -- GeoVax Labs, Inc. (OTCQB: GOVX), a biotechnology company developing human vaccines, today announced the presentation of positive results from HVTN 114, a phase 1 trial testing a late protein boost of participants from a phase 2a trial of GeoVax’s GOVX-B11 preventive HIV vaccine candidate. The presentation was made by the Protocol Chair, Paul A. Goepfert, M.D., University of Alabama, during the HIV Research for Prevention (HIVR4P) conference in Madrid, Spain. HVTN 114 was conducted by the HIV Vaccine Trials Network (HVTN) through the support of the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health (NIH).
GOVX-B11 consists of two experimental vaccine components – a recombinant DNA component and a recombinant live MVA (modified vaccinia Ankara) virus component. Both components produce non-infectious virus-like-particles (VLPs) in the cells of the vaccinated, HIV-negative, person. The DNA component is intended to prime a protective immune response, and the MVA component to boost the immune response. HVTN 114, which enrolled 27 individuals who previously participated in the HVTN 205 Phase 2a trial of GOVX-B11, tested the ability of late boosts (given on average 6.9 years after the original vaccination) to increase the antibody responses elicited by the original GeoVax vaccine regimen. These “late boosts” consisted of the GeoVax MVA62B vaccine candidate with or without a bivalent HIV-1 gp120 envelope glycoprotein vaccine candidate (AIDSVAX® B/E). AIDSVAX® B/E includes the same glycoproteins used to boost immune responses in participants in the 2009 RV144 clinical trial in Thailand led by the U.S. Military HIV Research Program and the Thai Ministry of Health. RV144, the only preventive HIV vaccine to show some limited efficacy, protected 31.2% of participants. In the HVTN 114 trial, participants received either (a) another MVA62B boost, (b) a combined boost of MVA62B and AIDSVAX® B/E, or (c) AIDSVAX® B/E alone. By far the most effective boost was the combination of MVA62B live vector and AIDSVAX®B/E proteins, which increased titers of antibodies to the HIV envelope glycoproteins by more than 600-fold.
Dr. Goepfert stated, “This study demonstrated that combining GOVX-B11 with a protein boost significantly enhanced the antibody responses, which might play a role in protecting the individuals against a genetically diverse pathogen such as HIV.”
Harriet L. Robinson, Ph.D. Director of HIV Vaccines at GeoVax, commented, “The results of HVTN 114 inform the use of protein boosts with the GOVX-B11 vaccine candidate and indicate that an effective way to boost antibody responses is to combine delivery of protein with the MVA. The results also show that late boosts can be highly effective in recalling immunological memory responses to the original vaccine and enhance the levels of antibodies that decrease with time. This trial was designed to develop regimens for a phase 2b efficacy trial and highlights the use of a vector plus protein boost strategy.”
Commenting on these recent, positive results, David A. Dodd, CEO of GeoVax stated, “We continue to be encouraged by the positive results and progress of our HIV preventive vaccine program. As recently reported by the NIH and the Gates Foundation, there continues to be a critical need for such a vaccine, providing a preventive intervention to the continued spread of HIV. Considering the HIV-related disparities among African American individuals, who comprise 43% of the 1.1 million people living with HIV in the US despite being only 12% of the nation’s total population, an effective vaccine should be part of an HIV elimination strategy. We therefore remain focused on progressing the successful development of an effective preventive vaccine, while encouraging all policy makers to continue support for effective, durable HIV preventive vaccines.”
About the HIV Vaccine Trials Network (HVTN)
The HVTN is the world’s largest publicly funded collaboration bringing together global study participants, communities and acclaimed scientific leadership on a journey to find an effective HIV vaccine. The HVTN’s mission is to fully characterize the safety, immunogenicity, and efficacy of HIV vaccine candidates with the goal of developing a safe and effective vaccine as rapidly as possible for prevention of HIV infections globally. The network is founded on a relationship of trust with global communities who work with specialized teams using science to serve global populations in the pursuit to find answers that will impact and change lives. Headquartered at the Fred Hutchinson Cancer Research Center in Seattle, Washington, the HVTN conducts all phases clinical trials and includes over 30 sites located on five continents. Website: www.hvtn.org
About GeoVax
GeoVax Labs, Inc., is a clinical-stage biotechnology company developing human vaccines against infectious diseases using its MVA-VLP vaccine platform. GeoVax was the winner of the 2018 “Best Biotech” Vaccine Industry Excellence Awards, a finalist for the 2018 “Best Prophylactic Vaccine” Award for its Zika vaccine at the World Vaccine Congress, as well as a finalist for Pipelines of Promise at Buzz of Bio 2018. The Company’s development programs are focused on vaccines against HIV, Zika, hemorrhagic fever viruses (Ebola, Sudan, Marburg, Lassa) and malaria. GeoVax also is evaluating the use of its MVA-VLP platform in cancer immunotherapy, and for therapeutic use in chronic Hepatitis B infections. GeoVax’s vaccine platform supports in vivoproduction of non-infectious VLPs from the cells of the very person receiving the vaccine. The production of VLPs in the person being vaccinated mimics virus production in a natural infection, stimulating both the humoral and cellular arms of the immune system to recognize, prevent, and control the target infection. For more information, visit www.geovax.com..
Forward-Looking Statements
Certain statements in this document are "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act. These statements are based on management's current expectations and are subject to uncertainty and changes in circumstances. Actual results may differ materially from those included in these statements due to a variety of factors, including whether: GeoVax can develop and manufacture its vaccines with the desired characteristics in a timely manner, GeoVax's vaccines will be safe for human use, GeoVax's vaccines will effectively prevent targeted infections in humans, GeoVax’s vaccines will receive regulatory approvals necessary to be licensed and marketed, GeoVax raises required capital to complete vaccine development, there is development of competitive products that may be more effective or easier to use than GeoVax's products, GeoVax will be able to enter into favorable manufacturing and distribution agreements, and other factors, over which GeoVax has no control. GeoVax assumes no obligation to update these forward-looking statements, and does not intend to do so. More information about these factors is contained in GeoVax's filings with the Securities and Exchange Commission including those set forth at "Risk Factors" in GeoVax's Form 10-K.