Project Summary/Abstract The goal of this study is to understand PrEP user choices, preferences, and implementation impact of the roll- out of long-acting injectable (LAI) PrEP alongside oral PrEP among women in Malawi. As the roll-out of expanded PrEP options increases globally, there is growing excitement that this could accelerate progress towards ending HIV and provide discreet, user-controlled prevention options for women. Yet, real-world choices and switches between oral and injectable PrEP products have not been evaluated on a large-scale and high rates of product continuation are not guaranteed as has been demonstrated with oral PrEP use globally. Thus, it is critical to understand PrEP user patterns and outcomes of PrEP implementation early during the expansion phase of new biomedical technologies. The PathToScale is already funded – it is an implementation science study which is rolling out injectable PrEP in Malawi to 9,900 people in real-world conditions in January 2024, alongside further PEPFAR supported allocations for oral PrEP. The proposed BetterInfo on PrEP study will leverage the PathToScale platform and critically extend work to evaluate use patterns, preferences, and decision-making among women discontinuing PrEP whose choices and outcomes will remain unknown in the absence of the proposed BetterInfo study. Specific Aim 1: Evaluate longitudinal patterns of oral and long-acting injectable PrEP use in women in Malawi and the impact of BetterInfo tracing approach on re-engagement in PrEP care. Specific Aim 2: Assess decision-making among injectable and oral PrEP users and providers, as well as preferences for implementation delivery and support. In-depth interviews with five sub-sets of PrEP user types traced (n=80) and healthcare providers/implementing partner stakeholders (n=16) will explore decision-making and implementation and behavioral facilitators and barriers to oral and injectable PrEP use guided by the theoretical domains framework (TDF) and COM-B model. Further, a discrete choice experiment/best worst scaling will be conducted among the sub-sample of traced discontinued PrEP users who remain at high risk for HIV acquisition (n=~270) to better understand preferences around PrEP product choice, clinical support and re-engagement strategies. Specific Aim 3: Co-design strategies for optimizing PrEP continuation and re-engagement to achieve implementation impact for women in Malawi by combining scenario-modeling and human centered design (HCD) workshops. This will be achieved by leveraging PathToScale and BetterInfo tracing data within mathematical models to estimate the comparative, community-level transmission impact of oral and injectable PrEP implementation strategies under different trajectories of PrEP use, and co-designing PrEP engagement and provider communication strategies through HCD workshops with the community partnership council, MOH and implementing partners/providers and clients, factoring in data across a...