Cross-posted from NIAID Now Blog
A durable end to the HIV/AIDS pandemic will require the development and widespread implementation of new and improved HIV prevention tools, according to NIAID Director Anthony S. Fauci, M.D. Yesterday, Dr. Fauci delivered a plenary lecture titled "Ending the HIV/AIDS Pandemic: The Critical Role of HIV Prevention Science" at the opening session of the HIV Research for Prevention (HIV R4P)conference, which is taking place this week in Madrid.
Despite the availability of HIV prevention modalities such as treatment as prevention and pre-exposure prophylaxis (PrEP), the rate of new HIV infections worldwide has declined minimally in recent years, Dr. Fauci noted. Adoption and implementation of existing prevention tools have been suboptimal, indicating a need for new and improved prevention options. Dr. Fauci discussed ongoing research to develop long-acting, non-vaccine forms of HIV prevention, such as monoclonal antibodies, as well as the various strategies scientists are employing to develop a safe and effective preventive HIV vaccine. A combination of vaccine and non-vaccine prevention modalities, if widely implemented, would play a critical role in ending the HIV/AIDS pandemic, he concluded.
An opening HIV R4P press conference moderated by John Mascola, M.D., director of NIAID's Vaccine Research Center (VRC), focused on recent advances toward a preventive HIV vaccine. An experimental HIV vaccine elicited monoclonal antibodies in monkeys that neutralized up to 59 percent of viruses from a globally representative panel of 208 HIV strains, VRC's Rui Kong, Ph.D., reported. The vaccine is based on the HIV fusion peptide, a vulnerable site on the spike on HIV's surface that NIAID scientists identified as a vaccine target in 2016. The new finding, which will be presented in a scientific session on Wednesday, builds on results published earlier this year demonstrating that a fusion peptide-based vaccine strategy can elicit broadly neutralizing antibodies (bNAbs) in animal models.
In a separate study presented at a scientific session today, VRC researchers found that five known bNAbs can prevent monkeys from becoming infected with an HIV-like virus. These bNAbs target four distinct sites on the HIV spike, including the fusion peptide, that remain the same as the virus mutates. A total of 62 animals received infusions of individual bNAbs one to five days prior to being exposed to the virus. All five bNAbs protected the monkeys against infection, with more potent bNAbs providing protection at lower doses. These results suggest that the four sites on the HIV spike targeted by these bNAbs are good candidates for an HIV vaccine designed to elicit protective antibodies.
AS Fauci. Ending the HIV/AIDS pandemic: The critical role of HIV prevention science. Oral presentation at HIV R4P 2018, Madrid, Spain.
R Kong et al. Fusion peptide-directed antibodies elicited in immunized rhesus macaques neutralized 59% of 208 wildtype HIV-1 strains. Oral presentation at HIV R4P 2018, Madrid, Spain.
A Pegu et al. Broadly neutralizing antibodies provide potent dose-dependent protection to rhesus macaques against mucosal SHIV challenge. Oral presentation at HIV R4P 2018, Madrid, Spain.