SUMMARY Adolescent girls and young women (AGYW; ages 15-24) in sub-Saharan Africa face the dual threats of HIV infection and unintended pregnancy that severely undermine their long-term wellbeing. However, despite the urgent need to reach AGYW with sexual and reproductive health (SRH) services, health systems are often ill equipped to overcome the numerous barriers to health care services faced by AGYW. We have successfully piloted and are now in the process of evaluating the effectiveness (in an ongoing cluster randomized controlled trial) of Malkia Klabu (MK), a loyalty program intervention that creates AGYW-friendly drug shops where AGYW can access HIV prevention services and contraception. The motivation for this approach is the growing recognition that drug shops, which are widely distributed and vastly outnumber health facilities, can promote beneficial health behaviors, bridge gaps in health services, and mitigate health workforce shortages. Though HIV testing is the gateway to HIV prevention and care, and self-testing with oral fluid holds promise for overcoming many of these obstacles, neither are widely accessible to AGYW. The goal of this proposed study is to build on the success of MK and move towards sustainability and scale-up, identify the critical supply-side features drug shops need to help independently sustain the MK demand-generating AGYW intervention, including HIVST kit distribution, following a fully subsidized research period. We therefore propose to extend our implementation-effectiveness trial study period and additionally test program adoption, implementation, and maintenance. To do so, we will emulate real-world market conditions by implementing shop-initiated HIVST procurement, phasing out HIVST kit subsidies (from 100% to 0), and testing continuation of 2 financing models for MK product reimbursements—fully reimbursable (government-supported scenario) vs none (fully privately supported scenario). After co-designing prosocial motivational pitches with our Pharmacy Advisory Board, we will test adoption and continuation of MK in control and intervention shops currently enrolled in our ongoing effectiveness trial, respectively, for 3 months (Aim 1), and maintenance by gradually phasing out subsidies of shop-initiated HIVST kit procurement over the next 36 months; without HIVST kit subsidies in the last phase, continuation will be tested by comparing fully reimbursed vs. fully shop-financed MK product distribution (Aim 2); mixed methods data will assess implementation, fidelity, receptivity, behavior change pathways, and motivational contexts for understanding shopkeeper engagement (Aim 3). At the end of the study, we will be well-positioned to inform our MOH and Pharmacy Council partners how best to scale MK under different HIVST kit subsidy levels and MK product reimbursement models. Importantly, our study will contribute to generalizable learning about the structures required for commercially sustainable public-private...