Approaches to effectively documenting prior single dose nevirapine exposure among women in Africa

Background: Single dose nevirapine (sdNVP) is widely used in resource-limited settings for the prevention of mother to child transmission of HIV, but can result in NVP resistance that negatively impacts the subsequent efficacy of maternal antiretroviral therapy (ART). It is important to determine prior sdNVP exposure status to help guide treatment decisions, but systematic data on approaches to documenting previous sdNVP ingestion are lacking. Aim: With the growing body of evidence of the effects of sdNVP exposure on subsequent choices of ART, we aim to highlight some of the practical challenges that exist in documenting prior sdNVP exposure or lack thereof. Materials and Methods: ACTG A5208 Optimized Combination Therapy after Nevirapine Exposure (OCTANE) is a randomized treatment trial of protease inhibitor vs. NVP-based ART that enrolled 745 HIV-infected women in 7 African countries. Documentation of previous exposure to sdNVP (or lack thereof) was collected prospectively and intensively, as were locally-available sources of such data. Results: All 243 women who were exposed to sdNVP recalled having taken sdNVP; written documentation of sdNVP exposure was found for 73% and an additional 20% identified having ingested a NVP tablet when the tablet was shown to them. Among 502 women not exposed to sdNVP, only 10 (2%) had written documentation of lack of sdNVP exposure. NVP resistance was detected in 33 (13.8%) of sdNVP-exposed and 1 of non-exposed women. Conclusion: Maternal self-report of prior sdNVP exposure was corroborated by supporting evidence in the majority of women participating in the trial.