Scientists are optimistic about three HIV vaccine trials — HVTN 702, Imbokodo and Mosaico — that are entering the final stages of testing, according to NBC News.
"We have three vaccines currently being tested in efficacy trials," Susan Buchbinder, MD, director of HIV Prevention Research at the San Francisco Department of Public Health and a chair for the Imbokodo and Mosaico trials, told NBC News. "It takes quite a bit to actually be promising enough in the earlier stages stages of trials to move you forward into an efficacy study."
The oldest ongoing trial, HVTN 702, is based on the only vaccine to ever show any efficacy against HIV — RV144. In a 2009 clinical trial, RV144 reduced the rate of HIV by about 30 percent. Results for HVTN 702 are expected in late 2020 or early 2021.
The second trial, Imbokodo, began in 2017 and completed enrollment for its second phase in May 2019. The vaccine uses "mosaic" immunogens to induce immune responses against numerous HIV strains, according to the National Institutes of Health. Imbokodo has only been tested in African women, with results expected in 2021.
In November, the third vaccine trial, Mosaico, was administered to its first patient. The vaccine is similar to Imbokodo, but its formulas are slightly different. Mosaico will be given to 3,800 gay men and transgender people at 57 sites in the U.S., Latin America and Europe. Findings are expected in 2023.
Even a partially effective vaccine could "have the power to change the trajectory of the epidemic," according to Dr. Buchbinder.