Phase III microbicide trial methodology: Opinions of experienced expanded safety trial participants in South Africa

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Article (peer-reviewed)

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In preparation for effectiveness trials of candidate vaginal microbicides, scientists are debating trial design and implementation challenges, including choice of control arm(s), product-sharing across arms, and visit schedules. This study involved a survey of South African women participating in an expanded safety trial of the candidate microbicide Carraguard gel. The first 100 consenting women who attended the study clinics in Ga-Rankuwa and Gugulethu (total N = 200) were interviewed; all women had been using a study gel for at least 6 months at the time of the interview. The study found that many participants thought that including a condoms-only arm would result in increased product-sharing, male partner resistance to trial participation and decreased enrollment; no clear patterns emerged regarding the potential effect on condom use and cohort retention. The majority of women preferred a monthly visit schedule, would be willing to use a product for 2 years, and thought that their product use would not decrease over time. Thus flexibility in trial design and implementation strategies is needed until evidence-based decisions can be made. When including a condoms-only arm, extra efforts should be made to explain the importance of all study arms to potential participants and to measure adherence and product-sharing.






Evaluation of the Informed Consent Process in the Phase 3 Study of the Candidate Microbicide Carraguard®