LAUSR

OBJECTIVE(S) The short-term safety of treatment interruptions, a necessary part of cure studies, is not well-established, particularly in women. We explored viral rebound kinetics and safety in a group of postpartum women discontinuing ART and compared results to males in historical interruption trials. DESIGN Prospective evaluation of time to virologic rebound. METHODS 1,076 asymptomatic, virally suppressed, postpartum women living with HIV enrolled in the PROMISE trial with baseline CD4 cell counts ≥ 350/mm underwent antiretroviral treatment (ART) discontinuation. Proportion with virologic suppression at weeks 4 and 12 were compared to participants in ACTG treatment interruption trials (91% male population). RESULTS In PROMISE, using interval censored methods, the estimated median time to HIV viral rebound was two weeks. An estimated 6% of women would remain virally suppressed at 30 weeks. Of those who had viral rebound by 30 weeks (N = 993), <4% experienced grade 3 or higher laboratory events, and 1% experienced WHO stage 2 or higher clinical events. Overall, <1% of participants progressed from WHO Stage 1 to Stage 2 or higher after discontinuation of ART, and 3.9% experienced a decline in CD4 cell count to < 350/mm or local treatment guidelines. A significantly higher proportion of women in PROMISE (25.4%) were virologically suppressed (<400 copies/mL) at 12 weeks compared to ACTG NWCS 371 participants (6.4%). CONCLUSION Temporary treatment interruptions in healthy, HIV-infected women with high CD4 cell counts can be safe. Potential sex differences need to be considered in cure studies examining time to virologic rebound.