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Primary Objectives

  • Explore larger contextual issues and specific aspects of the VOICE trial that positively and negatively affected participants’ actual and reported product use.
  • Explore the reasons, motivations, and context of engaging in receptive anal intercourse, (and rectal use of gel among VOICE participants in the gel group).

Study Summary
MTN-003D was a VOICE protocol substudy in which a subset of former participants was asked to complete one or two additional visits after their participation in the VOICE trial. If participants agreed to participate in the MTN-003D substudy, they completed an in-depth interview (IDI) and/or participated in a focus group discussion (FGD). MTN-003D investigated the factors influencing VOICE participants’ actual versus reported study product use and explored receptive anal intercourse (AI) behavior. In addition, motivations to join the trial, and in particular, risk perceptions were explored as one of the explanatory factors contributing to sub-optimal adherence. In Stage 2 of MTN-003D, participants were presented with their drug levels from blood samples collected during participation in VOICE. The drug levels were used as a tool to further explore product non-adherence and related behaviors.

MTN-003D completed follow-up on March 25, 2014. Primary results were presented at HIV Research for Prevention (HIV R4P) held on October 28-31, 2014, in Cape Town, South Africa. The two primary manuscripts were published in AIDS in October 2015 and AIDS and Behavior in August 2019 respectively. A total of 11 papers have been published from this study.

Primary Results
We interviewed 127 participants from South Africa, Uganda, and Zimbabwe. The most common reactions to pharmacokinetic results included surprise (41%; low pharmacokinetic), acceptance (39%; inconsistent pharmacokinetic) and happiness (65%; high pharmacokinetic). Based on participants' explanations, we developed a typology of adherence patterns: noninitiation, discontinuation, misimplementation (resulting from visit-driven use, variable taking, modified dosing or regimen) and adherence. Fear of product side effects/harm was a frequent concern, fueled by stories shared among participants. Although women with high pharmacokinetic levels reported similar concerns, several described strategies to overcome challenges. Women at all pharmacokinetic levels suggested real-time drug monitoring and feedback to improve adherence and reporting.

Protocol Chair(s)
Mensch, Barbara (Protocol Co-Chair)
Montgomery, Elizabeth (Protocol Co-Chair)
van der Straten, Ariane (Protocol Chair)
Protocol Title
An Exploratory Study of Potential Sources of Efficacy Dilution in the VOICE Trial
DAIDS Protocol ID
Oral Tablet
Truvada® (emtricitabine +tenofovir disoproxil fumarate)
Viread®  (tenofovir disoproxil fumarate)
Study Focus/Product Administration
Study Type
South Africa
Women (cisgender women, non‐transgender women)