NIH Reports Advance In Search For HIV Vaccine

Via press release from the National Institutes for Health:

An experimental vaccine regimen based on the structure of a vulnerable site on HIV elicited antibodies in mice, guinea pigs and monkeys that neutralize dozens of HIV strains from around the world. The findings were reported today in the journal Nature Medicine by researchers at the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, and their colleagues.

“NIH scientists have used their detailed knowledge of the structure of HIV to find an unusual site of vulnerability on the virus and design a novel and potentially powerful vaccine,” said NIAID Director Anthony S. Fauci, M.D. “This elegant study is a potentially important step forward in the ongoing quest to develop a safe and effective HIV vaccine.” A preliminary human trial of the new vaccine regimen is anticipated to begin in the second half of 2019.

Today’s report reflects one of two broad, complementary approaches NIAID is pursuing to develop an HIV vaccine. In one approach, scientists first identify powerful HIV antibodies that can neutralize many strains of the virus, and then try to elicit those antibodies with a vaccine based on the structure of the HIV surface protein where the antibodies bind. In other words, scientists start with the most promising part of the immune response and work to develop a vaccine that will induce it. This method was used to design the vaccine described today.

The other, empiric approach to HIV vaccine development begins by evaluating the most encouraging vaccine candidates for efficacy in people through clinical trials. Then scientists try to build on successful trial results by, for example, examining blood and other clinical specimens from study participants who received the vaccine to identify the most promising parts of the immune response. Researchers subsequently use this information to improve vaccination approaches for future trials. This method was used to develop the HIV vaccine regimen tested in the RV144 clinical trial (link is external) and the HIV vaccine regimens currently under study in the HVTN 702 and Imbokodo clinical trials.