Estimated adherence to the Dapivirine Vaginal Ring and its associated factors among African women: A systematic review and meta-analysis

The Dapivirine Vaginal Ring (DVR), a silicone circular ring, continuously distributes Dapivirine into the vagina to prevent HIV infection. We summarized evidence on adherence to DVR for HIV-1 prevention among African women 16-45 years old and described the factors associated with adherence. We searched different databased from inception to December 2024. We included observational studies and randomized trials. Our primary outcome was adherence to DVR, explored as women adhering, mean adherence, and visit/ring adherence. Pairs of reviewers independently screened for eligible studies and extracted relevant data. We performed a random-effects meta-analysis of proportions and means for DVR adherence. The certainty of the evidence was assessed using the GRADE approach. Our search retrieved 217 records, of which 15 articles published between 2016 and 2024 were found (seven unique studies). Across the seven included studies, 2,424 women using DVR were reported in four studies. Across the included studies, adherence to the vaginal ring was measured as proportion with good adherence (4 studies), mean adherence (1 study), number of follow-ups with good adherence (1 study); and 1 study reported both mean adherence and number of returned rings deemed adherent. Adherence to the DVR among women was generally good, with a pooled mean estimate of 84% (95% CI: 75%-91%), although the certainty of evidence was very low. The proportion of women who adhered was 76% (95% CI: 63%-87%). Appropriate use of rings was 74% (95% CI 74-75%) and visits with adherence reported was 89% (95% CI 89-90%). Factors influencing adherence were cross-cutting across multiple domains. The evidence suggests generally good adherence to the DVR, which may enhance its effectiveness in reducing HIV infections in real-world settings; however, the certainty of this evidence is low. We encourage further implementation research, particularly individual patient data meta-analyses, to assess adherence more accurately.