Sharing objective measures of adherence to a vaginal microbicide promoted candor about actual use and bolstered motivation to prevent HIV during MTN-025/HOPE


BACKGROUND: Discrepancies between self-reported and actual adherence to biomedical HIV interventions can compromise the integrity of clinical trials. One solution is to monitor adherence more objectively through biological assays. However, it is not well understood how to communicate these metrics in ways that foster honest reporting rather than defensiveness.
METHODS: MTN-025/HOPE was a Phase 3b open-label trial of a vaginal ring to prevent HIV, conducted across four sub-Saharan African countries. The trial involved testing each ring to measure its residual drug level (RDL), an objective marker of adherence. During successive adherence counseling sessions at Months 3, 6, 9, and 12, counselors shared with participants each ring's RDL, re-conceptualized as a level of protection ranging from 0 'No Protection' to 3 'High Protection.' After the trial, from July 2018-May 2019, we interviewed 22 counselors and conducted a matrix analysis to characterize their perspectives about RDL conversations.
RESULTS: Counselors perceived that participants appreciated RDL feedback as an indication of their protection from HIV. Indeed, reactions varied depending on the RDL. Higher drug levels (RDL=2 or 3) stimulated elation and relief whereas lower levels (RDL=0 or 1) resulted in disappointment and, more rarely, in anger when participants self-reported higher adherence. A nonjudgmental stance and support for autonomy to choose alternatives to the ring promoted disclosure of causes of lower adherence that otherwise might have remained forgotten (e.g., taking the ring out during menses) or concealed (e.g., preferring not to use the ring). Reframing RDL monitoring as 'protection' rather than 'adherence' also helped pivot from numerical results toward the trial's ultimate goal of HIV prevention. This emphasis on women's motivations to prevent HIV, rather than on ring use, encouraged consistent users to continue and infrequent users to switch to an alternative HIV prevention approach. Counselors noted that adherence conversations might have been more cursory if based solely on self-report, without the anchoring metric of a woman's current protection against HIV.
CONCLUSIONS: Personalizing feedback from objective adherence ratings is complex and requires careful navigation to minimize defensiveness but can also be implemented in ways that motivate disclosure of non-adherence and evoke commitment to preventing HIV acquisition.