Engaging Zimbabwean men and stakeholders in the co-adaptation of peer-delivered HIV self-testing: iterative prototyping of the IMPERATIVE Trial

Introduction: HIV testing and pre-exposure prophylaxis (PrEP) are efficacious HIV prevention strategies, but uptake remains low among Sub-Saharan African men. Peer-delivered approaches may improve engagement. We developed an intervention combining peer-delivered oral HIV self-testing (HIVST) with incentivized peer referral to HIV services and an SMS-based HIV risk assessment among men in eastern Zimbabwe (IMPERATIVE Trial: NCT06370923). We co-adapted the intervention through iterative prototyping (IP) to enhance its acceptability, feasibility, and potential effectiveness. Methods: From November 2023 to June 2024, we implemented a novel IP framework to refine and test the intervention. Four primary distributors (PDs) were trained to deliver HIVSTs to three peers and refer them to clinic services. Peers could become secondary distributors (SDs), obtain HIVSTs from community hubs and distribute them further. Qualitative data were collected alongside intervention testing to adapt the intervention over two iterations. Activities included three forum theatre workshops, one community advisory board meeting, 25 in-depth interviews, four focus group discussions, and eight observational reports involving men, implementers, stakeholders, and advisory board members. Additionally, 20 men completed baseline and one-week follow-up surveys. Quantitative data were analysed descriptively; qualitative data were analysed using thematic analysis. Results: During testing, HIVST uptake was 100% among PDs, 90% among PD-recruited peers, and 63% among SD-recruited peers. Among self-testers, 50% sought confirmatory testing and about one-quarter initiated PrEP (PDs 25%, PD-recruited peers 30%, SD-recruited peers 25%). Participants viewed the intervention positively and anticipated increased HIV testing and PrEP initiation. Four areas for refinement were identified: recruitment, information dissemination, incentives, and socio-cultural factors. Participant recommendations were adopted before randomised controlled trial testing. Conclusion: Peer-delivered HIVST with referral to HIV services shows promise for engaging Zimbabwean men. The IP framework incorporating participant recommendations enhanced intervention design and delivery within the IMPERATIVE trial. This methodology may inform future intervention development in similar settings.