Initiation of antiretroviral treatment protects partners from HIV infection

Men and women infected with HIV reduced the risk of transmitting the virus to their sexual partners by starting oral antiretroviral therapy, according to findings from a large multinational clinical study conducted by the HIV Prevention Trials Network, a global partnership dedicated to reducing the transmission of HIV through biomedical, behavioral, and structural interventions.

The study, known as HPTN 052, evaluated whether immediate versus delayed use of oral antiretroviral therapy, also known as ART, by HIV-infected individuals would reduce transmission of HIV to their HIV-uninfected partners and potentially benefit the HIV-infected individual as well. Findings from the study were reviewed by an independent Data and Safety Monitoring Board.

The DSMB concluded that initiation of ART by HIV-infected individuals substantially protected their HIV-uninfected sexual partners from acquiring HIV infection, with a 96 percent reduction in risk of HIV transmission. The DSMB recommended that the results be released as soon as possible and that the findings be shared with study participants and investigators.

“This is excellent news,” said Dr. Myron Cohen of the University of North Carolina at Chapel Hill, principal investigator of the study. “The study was designed to evaluate the benefit to the sexual partner as well as the benefit to the HIV-infected person. This is the first randomized clinical trial to definitively indicate that an HIV-infected individual can reduce sexual transmission of HIV to an uninfected partner by beginning antiretroviral therapy sooner.”

SCHARP serves as primary statistical center

The Hutchinson Center’s Statistical Center for HIV/AIDS Research and Prevention (SCHARP) in the Vaccine and Infectious Disease Division is the primary statistical center for the study.

HPTN 052 began in April 2005 and enrolled 1,763 couples in which one member is HIV-infected and the other is not, the vast majority of which (97 percent) were heterosexual. The study was conducted at 13 sites across Africa, Asia and the Americas. The HIV-infected person was required to have a CD4 cell count between 350-550 per cubic millimeter at enrollment, and therefore did not require HIV treatment for his or her own health. Couples were randomized to one of two groups. In one group, the HIV-infected person immediately began taking ART. In the other group, the HIV-infected person began ART when his or her CD4 cell count fell below 250 cells/mm or if he/she developed an AIDS-related illness.

HPTN is a partnership between scientists and communities around the world to develop, evaluate, and implement biomedical, behavioral, and structural interventions to reduce the transmission of HIV. HPTN is largely funded by National Institute for Allergy and Infectious Diseases primarily funds HPTN, with additional funding from the National Institutes of Health’s National Institute on Drug Abuse and National Institute for Mental Health.

[Adapted from a HPTN news release]