Establishing a Pharmacy-Based Pre-Exposure Prophylaxis Program for Young Women Who Sell Sex: Protocol for a Randomized Controlled Trial

Background: Sex workers (SWs) are at risk of acquiring HIV infections. Despite this, SWs have low uptake of relevant preventive measures, such as HIV pre-exposure prophylaxis (PrEP). Community-based programs that make PrEP convenient and accessible have the potential to drive PrEP continuation and reduce HIV risk. 

Objective: This study aims to describe the co-development and piloting of the Together Optimizing PrEP Access in Zimbabwe (TOPAZ) intervention—where SWs have the opportunity to access PrEP refills through pharmacies in Zimbabwe. Methods: Using a participatory process, the TOPAZ intervention will be collaboratively developed with pharmacy owners and SWs. TOPAZ comprises the provision of safe and convenient spaces for PrEP refill pickups bundled with a gift voucher incentive at pharmacies. Formative research comprising focus group discussions and in-depth interviews with SWs, pharmacists, and stakeholders will inform the development of the preliminary model (aim 1). A cluster-randomized pilot trial will evaluate the impact of the PrEP-in-pharmacy intervention, compared to standard clinic-based pickup in the key populations program, on PrEP retention at 3, 6, 9, and 12 months after initiation (aim 2). The outcome of the pilot trial will be a comparison of PrEP retention at 6 months after initiation between study arms. We will also compare PrEP retention among SWs aged between 18 and 24 years at 6 months and among participants remaining active in sex work at 6 months. We will use the Generalized Estimation Equations model to generate risk differences and 95% CIs for PrEP retention in intervention versus comparison arms. Analysis will follow an intent-to-treat approach. Finally, a mixed methods study will be conducted to understand the potential for scaling TOPAZ for SWs; insights from this study will inform the design of a future effectiveness trial (aim 3). Proctor’s implementation outcomes, namely, acceptability, adoption, appropriateness, feasibility, fidelity, and penetration of the pharmacy-based PrEP refill program, will be evaluated by triangulation of program data and qualitative interviews. 

Results: This study began the enrollment of participants in March 2024. Data collection ended in May 2025. The final comprehensive analysis of the results will be conducted in February 2026 after all the data have been collected and reviewed comprehensively. 

Conclusions: This study will report on the feasibility, acceptability, and effectiveness of pharmacy-based PrEP refills to improve PrEP continuation among women who sell sex. If successful, this preliminary study will pave the way for a future effectiveness trial to evaluate this intervention more comprehensively.