Abstract
In the CAPRISA 004 trial, adherence was estimated as the proportion of reported sex acts covered by two gel doses, which was assessed by counting returned empty gel applicators. The returned empty applicators were inspected visually in a standardized manner for residue on the outside of the applicator, as an indicator of vaginal insertion. Over 15 months, spanning 11,839 study visits by 838 women, a total of 59,800 returned empty applicators were inspected. By visual assessment, 77.5 % of these applicators appeared to have been inserted. To test the accuracy of the assessment we fitted a Cox model and found that the risk for HIV infection was doubled when less than half of the returned empty applicators had been assessed as not inserted in the vagina. Visual inspection enhanced both the accuracy of the adherence measurement and aided identification of mechanical problems with applicator use experienced by women in the trial.
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Acknowledgments
We pay tribute to the women who participated in this trial; their dedication and commitment made this study possible. The CAPRISA 004 Tenofovir Gel trial is supported by the Centre for the AIDS Program of Research in South Africa (CAPRISA), the United States Agency for International Development (USAID), Family Health International (FHI) (cooperative agreement # GPO-A-00-05-00022-00, contract # 132119), and LIFElab, a biotechnology center of the South African Department of Science and Technology. Support from CONRAD for the product manufacturing and packaging as well as support from Gilead Sciences for the Tenofovir used in the production of gel is gratefully acknowledged. We acknowledge the University of North Carolina Center for AIDS Research (UNC CFAR Grant P30 AI50410) for provision of vaginal aspirators and assay of tenofovir samples. We thank the US National Institutes for Health’s Comprehensive International Program of Research on AIDS (CIPRA Grant # AI51794) and the Columbia University—Southern African Fogarty AIDS International Training and Research Programme (AITRP Grant # D43TW00231) for the research infrastructure and training that made this trial possible. We acknowledge Londeka Zondi, Zanele Mkhize, Cynthia Velile Ngcobo, Nolwazi Thandiwe Nzimande, Gugulethu Masinga, Bhavna Maharaj, Kershani Naidoo, Bernadene Moodley and Laura Chelini for conducting the VIREA.
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Gengiah, T.N., Mansoor, L.E., Upfold, M. et al. Measuring Adherence by Visual Inspection of Returned Empty Gel Applicators in the CAPRISA 004 Microbicide Trial. AIDS Behav 18, 820–825 (2014). https://doi.org/10.1007/s10461-014-0749-4
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DOI: https://doi.org/10.1007/s10461-014-0749-4