Sharing Objective Measures of Adherence to a Vaginal Microbicide Promotes Candor About Actual Use and Bolsters Motivation to Prevent HIV.

Discrepancies between self-reported and actual adherence to biomedical HIV interventions is common and in clinical trials can compromise the integrity of findings. One solution is to monitor adherence biomarkers, but it is not well understood how to navigate biomarker feedback with participants. We surveyed 42 counselors and interviewed a subset of 22 to characterize their perspectives about communicating with participants about residual drug levels, an objective marker of adherence, within MTN-025/HOPE, a Phase 3b clinical trial of a vaginal ring to prevent HIV. When biomarkers indicated low drug levels that mismatched high adherence by self-report, counselors encountered barriers to acceptance and comprehension among participants. However, discrepancies between low self-report and higher drug levels generally stimulated candor. Women recollected times they had not used the product and disclosed problems that counselors thought might otherwise have remained forgotten or concealed. Navigating conversations toward HIV prevention was easier at mid-range drug levels and when women indicated motivation to prevent HIV. Ratings of residual drug level offered a somewhat objective measure of adherence and protection that counselors perceived as meaningful to participants and as a valuable catalyst for broaching conversation about HIV prevention. However, communication about drug levels required that counselors navigate emotional barriers, respond skillfully to questions about accuracy, and pivot conversations non-judgmentally away from numerical results and toward the priority of HIV prevention. Findings suggest a role for biomarker feedback in future clinical trials as well as other clinical contexts where biomarkers may be monitored, to motivate disclosure of actual adherence and movement toward HIV prevention.Clinical Trial Number NCT02858037.