Adherence in the CAPRISA 004 Tenofovir Gel Microbicide Trial
High adherence is key to microbicide effectiveness. Here we provide a description of adherence interventions and the adherence rates achieved in the CAPRISA 004 Tenofovir gel trial. Adherence support for the before-and-after dosing strategy (BAT 24) was provided at enrolment and at each monthly study visit. This initially comprised individual counselling and was replaced midway by a structured theory-based adherence support program (ASP) based on motivational interviewing. The 889 women were followed for an average of 18 months and attended a total of 17,031 monthly visits. On average women reported five sex acts and returned 5.9 empty applicators per month. The adherence rate based on applicator count in relation to all reported sex acts was 72.2 % compared to the 82.0 % self-reported adherence during the last sex act. Adherence support activities, which achieve levels of adherence similar to or better than those achieved by the CAPRISA 004 ASP, will be critical to the success of future microbicide trials.
KeywordsAdherence Adherence support Adherence measures Microbicides Clinical trial HIV prevention
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 was supported by the Centre for the AIDS Program of Research in South Africa (CAPRISA), the United States Agency for International Development (USAID), FHI (co-operative agreement # GPO-A-00-05-00022-00, contract # 132119), and the Technology Innovation Agency (formerly known as LIFElab), a biotechnology centre 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 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.
- 1.UNAIDS. Global report: UNAIDS report on the global AIDS epidemic 2012. Available from: Global report: UNAIDS report on the global AIDS epidemic 2012. Geneva: Joint United Nations Programme on HIV/AIDS2012. Accessed 25 Mar 2013.Google Scholar
- 9.Tolley EE, Harrison PF, Goetghebeur E, et al. Adherence and its measurement in phase 2/3 microbicide trials. AIDS Behav. 2010;14(5):1124–36.Google Scholar
- 11.Marrazzo J, Ramjee G, Nair G, et al., editors. Pre-exposure prophylaxis for HIV in women: daily oral tenofovir, oral tenofovir/emtricitabine, or vaginal tenofovir gel in the VOICE study (MTN 003). Conference of Retroviral and Opportunistic Infections; 2013. Goergia World Congress Centre, Atlanta.Google Scholar
- 13.Lagakos S, Gable A, editors. Methodological challenges in biomedical HIV prevention trials. Washington, DC: National Academies Press; 2008.Google Scholar
- 14.Gilead Sciences Inc. Investigators Brochure: tenofovir gel (GS-1278). 5th ed. Foster City: California Gilead Sciences; 2013.Google Scholar
- 18.Fisher JD, Fisher WA. The information–motivation–behavioural skills model. In: DiClemente RJ, Crosby RA, Kegler MC, editors. Emerging theories in health promotion practice and research. Jossey-Bass: San Francisco; 2002. p. 40–70.Google Scholar
- 19.Misovich S, Fisher J, Martinez T, et al. Predicting breast self-examination: a test of the information–motivation–behavioural skills model. J Appl Psychol. 2003;33:775.Google Scholar
- 28.Mansoor LE, Abdool Karim Q, Werner L, et al. Impact of an adherence intervention on the effectiveness of tenofovir gel in the CAPRISA 004 trial. AIDS Behav. 2014. doi: 10.1007/s10461-014-0752-9.
- 29.Mauck CK, Van de Straten A. Using objective markers to assess participant behavior in HIV prevention trials of vaginal microbicides. J Acquir Immune Defic Syndr. 1999;2008(49):64–9.Google Scholar
- 32.Mngadi KT, Maarschalk S, Grobler AC, et al. Disclosure of microbicide gel use to sexual partners: influence on adherence in the CAPRISA 004 trial. AIDS Behav. 2014. doi: 10.1007/s10461-014-0696-0.