Observational studies have previously shown that antiretroviral therapy (ART) may reduce the transmission of HIV in serodiscordant couples (Cochrane Database Syst Rev 2011 May 11;(5):CD009153). A new unblinded randomized trial suggests that early initiation of ART for the infected partner may reduce transmission more effectively than delaying ART until the CD4 count has fallen (level 2 [mid-level] evidence). A total of 1,763 stable heterosexual couples from 9 countries (54% African participants) in which 1 partner was HIV 1-positive were randomized to early ART vs. delayed ART. Half of the infected partners were male, and the CD4 counts in the infected partners at the start of the trial ranged from 350-550 cells/mcL. The early group started therapy immediately. The delayed group began treatment following 2 consecutive tests showing CD4 count ? 250 cells/mcL or after the development of AIDS-related illness. All participants had counseling on risk reduction and condom use. Uninfected partners were tested for HIV every 3 months.
In median 1.7 years of follow-up, there were 39 total cases of HIV transmission, of which 28 were virologically linked to the infected partner. Of the linked transmissions, there was 1 case in the early ART group vs. 27 cases in the delayed ART group, with incidence rates of 0.1 vs. 1.7 per 100 person-years (hazard ratio 0.04, p< 0.001). The infected partners were also followed for clinical events including death, WHO stage 4 events, severe bacterial infections, and pulmonary tuberculosis. Early ART was associated with a reduced incidence of clinical events (incidence rate 2.4 vs. 4 per 100 person-years, hazard ratio 0.59, p = 0.01) (N Engl J Med 2011 Jul 18 early online).
For more information, see the HIV infection topic in DynaMed.