IAS welcomes new data on the potential forbroadly neutralizing antibodies (bNAbs) to prevent HIV infection

Results of the Antibody Mediated Prevention (AMP) studies to be presented at the IAS HIV Research for Prevention (HIVR4P // Virtual) conference.

 IAS – the International AIDS Society – welcomes new results from two proof-of-concept studies (HVTN 704/HPTN 085 and HVTN 703/HPTN 081- the AMP Studies) demonstrating that infusions of the broadly neutralizing monoclonal HIV antibody (bNAb) VRC01 can prevent some HIV infections.

Results of the study were discussed in a press conference today prior to the opening of the 4th HIV Research for Prevention Conference (HIVR4P // Virtual), and will be reviewed in more detail in two HIVR4P conference presentations on Wednesday 27 January at 15.00 UTC and Thursday 4 February at 17.30 UTC.

The AMP results include data from more than 4,600 participants in two studies that enrolled HIV-negative men and transgender people who have sex with men in the U.S., Brazil and Peru (HVTN 704/HPTN 085) and HIV-negative cisgender women in sub-Saharan Africa (HVTN 703/HPTN 081).

The studies build off of traditional concepts of vaccination, in which a vaccine primes the immune system to make antibodies that can neutralize an infectious agent such as HIV. Instead of priming recipients to create antibodies, the AMP study infused participants with an antibody called VRC01, or a placebo, at eight-week intervals over 80 weeks.

With this approach, known as passive immunization, AMP participants who received the antibody were 75 per cent less likely to become infected with a strain of HIV that had been shown to be sensitive to VRC01 in in vitro studies.

Importantly, however, the AMP studies also found that VRC01 was not protective against many strains of the virus. The study findings support the need for additional research on infusions with multiple antibodies capable of achieving broader protection against a variety of HIV strains.

“AMP is an exciting proof-of-concept of a new and innovative potential form of HIV prevention,” said Adeeba Kamarulzaman, President of the IAS. “These studies open an important door to what may one day become yet another important approach to preventing HIV infection.”   

“Like most innovative research studies, AMP produced complex results that also raise important new questions for researchers,” said Roger Tatoud, Deputy Director of HIV Programmes and Advocacy at IAS and head of the IAS’s Global HIV Vaccine Enterprise.

“Moving forward, the field must consider the dual challenges of developing cocktails of antibodies that are both more broadly effective and more easily and practically delivered, while remaining affordable and accessible.”

To help address those questions, the IAS will host an upcoming series of webinars with AMP study investigators to explore the results of these studies and their implications for future development of passive immunization approaches. Registration for the HIVR4P // Virtual conference (26 & 27 January and 3 & 4 February), which includes presentation of the AMP results along with the latest research on antibody-mediated prevention, HIV vaccines, pre-exposure prophylaxis, treatment as prevention and new and emerging forms of prevention is available at: https://www.hivr4p.org/registration/

“AMP was a well-conducted study with excellent participant safety and retention,” said SusanBuchbinder, Chair of the IAS’s Global HIV Vaccine Enterprise Advisory Group.

“We congratulate everyone involved, and in particular the study volunteers and team, who have made a vital contribution to HIV prevention research. With 1.7 million new HIV infections last year, HIV remains an enormous global health crisis that requires multiple prevention options. AMP demonstrates both the importance and the value of maintaining a strong, ongoing commitment to HIV prevention research.”

Additional Enterprise materials on both of the AMP studies and on Passive Immunization are available at https://vaccineenterprise.org/