Reduced HIV-1 Infection Incidence With Vaginal Ring
Monthly vaginal ring containing dapivirine reduces risk of HIV-1 infection among African women
WEDNESDAY, Feb. 24, 2016 (HealthDay News) -- A monthly vaginal ring containing dapivirine can reduce the incidence of HIV-1 infection, according to a study published online Feb. 22 in the New England Journal of Medicine to coincide with the annual Conference on Retroviruses and Opportunistic Infections, held from Feb. 22 to 25 in Boston.
Jared M. Baeten, M.D., Ph.D., from the University of Washington in Seattle, and colleagues conducted a phase 3 trial of a monthly vaginal ring containing dapivirine involving 2,629 women aged 18 to 45 years in Malawi, South Africa, Uganda, and Zimbabwe.
The researchers identified 168 HIV-1 infections: 71 in the dapivirine group and 97 in the placebo group (incidence, 3.3 and 4.5 per 100 person-years, respectively), with 27 percent lower incidence in the dapivirine group (P = 0.05). Exclusion of data from two sites with reduced rates of retention and adherence resulted in 37 percent lower HIV-1 infection incidence in the dapivirine group (P = 0.007). Higher rates of HIV-1 protection were seen for women aged older than 21 years, in post-hoc analysis (56 percent; P < 0.001), but not for those aged 21 years or younger (−27 percent; P = 0.45); this difference correlated with reduced adherence.
"A monthly vaginal ring containing dapivirine reduced the risk of HIV-1 infection among African women, with increased efficacy in subgroups with evidence of increased adherence," the authors write.