Which ART Regimen Is Best After Receipt of Single-Dose Nevirapine?

Women who receive single-dose nevirapine during labor may be better off with subsequent antiretroviral therapy (ART) regimens that contain lopinavir/ritonavir rather than nevirapine, according to a recent press release from the National Institute of Allergy and Infectious Diseases. This finding arose during a recent interim analysis of the phase III OCTANE trial, which is taking place in seven African countries. Nevirapine is widely used throughout the developing world for both treatment of HIV infection and prevention of mother-to-child HIV transmission.

A total of 243 HIV-infected women in the OCTANE trial who previously had received single-dose nevirapine were randomized to receive FTC/tenofovir plus either nevirapine or lopinavir/r. The primary outcome was a composite of death or virologic failure, with the latter defined as a <10-fold reduction in viral load by week 12 or a viral-load measurement ≥400 copies/mL at or after week 24.

During a median follow-up of 66 weeks, 24% of women in the nevirapine group died or experienced virologic failure, compared with only 7% in the lopinavir/r group. The difference between treatment groups was particularly striking (38% vs. 0%) among women who had evidence of nevirapine resistance at baseline. (Resistance testing was done retrospectively, and results were not available in real time.) However, on a more positive note, the two regimens appeared to be comparable in the small group of women who deferred ART initiation until at least 2 years after delivery. The proportion of these women who died or experienced virologic failure was 8% in the nevirapine group and 10% in the lopinavir/r group.

Per the Data and Safety Monitoring Board, study participants are being informed of these preliminary results and counseled to talk to their clinicians about how to proceed. Lopinavir/r is being made available to those in the nevirapine group who choose to switch therapy. Baseline resistance results also are now available and being shared with participants. Follow-up of all participants will continue as planned, until June 2009. A concurrent OCTANE trial, comparing the same two regimens among 502 women who have never taken single-dose nevirapine, also will continue as planned. These results will be submitted for possible presentation at the upcoming Retrovirus Conference in Montreal.