HIV vaccine could be nail in coffin for disease

If it is effectively developed as part of a new South African study, an HIV vaccine could help wipe out the disease globally, officials say.

A clinical study that recently began in South Africa, called HVTN 702, is testing whether an experimental vaccine regimen safely prevents HIV infection among South African adults. The study involves a new version of the only HIV vaccine candidate ever shown to provide some protection against the virus, according to the NIH, which is supporting the trial.

“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,” said Anthony S. Fauci, MD, Director of the National Institute of Allergy and Infectious Diseases (NIAID) at NIH, and a co-funder of the trial. “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.”

HVTN 702 aims to enroll 5,400 men and women, making it the largest and most advanced HIV vaccine clinical trial to take place in South Africa, where more than 1,000 people become infected with HIV every day, NIH said.

The experimental vaccine regimen being tested in HVTN 702 is based on the one investigated in the RV144 clinical trial in Thailand led by the U.S. Military HIV Research Program and the Thai Ministry of Health.

The Thai trial delivered landmark results in 2009 when it found, for the first time, that a vaccine could prevent HIV infection-- albeit modestly. The experimental vaccine regimen tested in that trial was found to be 31.2% effective at preventing HIV infection over the 3.5-year follow-up after vaccination.

The new regimen aims to provide greater and more sustained protection than the RV144 regimen and has been adapted to the HIV subtype that predominates in southern Africa, a region that includes the country of South Africa.

“HIV has taken a devastating toll in South Africa, but now we begin a scientific exploration that could hold great promise for our country. If an HIV vaccine were found to work in South Africa, it could dramatically alter the course of the pandemic,” said HVTN 702 Protocol Chair Glenda Gray, a Research Professor of Pediatrics at the University of the Witwatersrand, Johannesburg.

In the new HVTN 702 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.

The NIAID-funded HIV Vaccine Trials Network (HVTN) is conducting the trial at 15 sites across South Africa. Results are expected in late 2020.