Dapivirine Vaginal Ring Showed Modest Efficacy at Preventing HIV Infection in African Women

Preexposure prophylaxis with antiretroviral therapy can lower risk for HIV acquisition, but the efficacy of this approach depends on adherence to daily use of medication (e.g., in vaginal gel). To assess the efficacy of a vaginal ring containing dapivirine, a nonnucleoside reverse-transcriptase inhibitor, investigators randomized 1959 women in South Africa and Uganda to dapivirine-containing or placebo rings changed every 4 weeks for up to 2 years.

HIV acquisition rates were 6.1/100 person-years in the placebo group versus 4.1/100 person-years in the dapivirine group, a statistically significant 31% reduction in incidence. The reduction in HIV acquisition was 37% in women older than 21 but only 15% in younger women. Rings were well tolerated…