First HIV Vaccine Trials to Begin in South Africa

The first clinical trials for an HIV vaccine will finally be launched.

The study, which is called HVTN 702, will involve a new version of the experimental vaccine that shows the biggest potential to protect against the HIV virus. The trials will be conducted in South Africa, enrolling about 5,400 HIV-negative but sexually active men and women.

"If deployed alongside our current armory of proven HIV prevention tools, a safe and effective vaccine could be the final nail in the coffin for HIV," Dr. Anthony Fauci, director of the National Institutes of Health's (NIH) National Institute of Allergy and Infectious Diseases (NIAID), said in a statement.

"Even a moderately effective vaccine would significantly decrease the burden of HIV disease over time in countries and populations with high rates of HIV infection, such as South Africa."

The HVTN 702 study is a large, advanced-stage clinical trial that aims to determine if an experimental vaccine regimen is safe, tolerable and effective at protecting against the HIV virus.

The experimental vaccine regimen being tested for the study is based on the RV144 regimen, which was tested in Thailand four years ago on 16,000 people. The test, which was led by the U.S. Military HIV Research Program and the Thai Ministry of Health, was the first time a vaccine was found to be capable of preventing HIV infection.

During the Thai trials, the vaccine was found to be 31.2 percent effective at preventing the infection over the 3.5-year follow-up after vaccination. For the new study, the design, schedule and components of the RV144 vaccine regimen have been modified in an attempt to increase the magnitude and duration of vaccine-elicited protective immune responses.

If the vaccine proves to be 50 to 60 percent effective, drugmakers Sanofi Pasteur and GlaxoSmithKline to begin licensing negotiations with the South African government, Chicago Tribune reports.

"If this study shows efficacy . . . this would be a tectonic, historic event for HIV," Nelson L. Michael, director of the U.S. Military HIV Research Program, told Chicago Tribune.