Combination antiretroviral treatment for women previously treated only in pregnancy: Week 24 results of AIDS clinical trials group protocol A5227

Background: Women with HIV and prior exposure to combination antiretroviral therapy (cART) solely for prevention of motherto- child transmission (pMTCT) need to know whether they can later be treated successfully with a commonly used regimen of efavirenz (EFV) and coformulated emtricitabine (FTC) and tenofovir disoproxil fumarate (TDF). Methods: Nonpregnant women with plasma HIV-1 RNA of $500 copies per milliliter, previously cART exposed for pMTCT only, were eligible if they were off ART for $24 weeks before entry, were without evidence of drug resistance on standard genotyping, and were ready to start EFV plus FTC/TDF. The primary endpoint was virologic response (defined as plasma HIV RNA ,400 copies/mL) at 24 weeks. Results: Fifty-four women were enrolled between October 2007 and December 2009; 52 of 54 completed 24 weeks of follow-up. Median baseline CD4+ T-cell count was 265/mm3 and baseline plasma HIV-1 RNA was 4.6 log10 copies per milliliter. Median prior cART duration was 14 weeks, and median time elapsed from the last pMTCT dose to entry was 22 months. Virologic response at 24 weeks was observed in 42 of 52 women or 81% (exact 95% confidence interval: 68% to 90%). There were no differences in response by country, by number, or class of prior pMTCT exposures. Although confirmed virologic failure occurred in 8 women, no virologic failures were observed in women reporting perfect early adherence. Conclusions: In this first prospective clinical trial studying combination antiretroviral retreatment in women with a history of pregnancy-limited cART, the observed virologic response to TDF/ FTC and EFV at 24 weeks was 81%. Virologic failures occurred and correlated with self-reported nonadherence.