Project Summary This collaboration between University of the Philippines Manila (UPM) and Brown University responds to PAR-19-326 (Reducing Stigma to Improve HIV/AIDS Prevention, Treatment and Care in Low- and Middle- Income Countries) by proposing rigorous procedures to develop and pilot test a gender-affirmation and stigma- reduction intervention to promote HIV self-testing (HST), behavioral risk reduction, and use of relevant HIV prevention/care and gender-related services for transgender women (TW) in the Philippines. TW are a priority population for HIV intervention research in the Philippines, where one of the world’s fastest growing epidemic currently takes place. Gender-minority stigma is a critical barrier to engaging Filipina TW in HIV services, and gender-affirmative interventions can counteract anticipated and internalized gender-minority stigma in this population. Currently, there are few evidence-supported gender-affirmative interventions for addressing gender-minority stigma and meeting the unique needs of TW in LMICs generally, and in the Philippines particularly. Building on the Gender Minority Stress framework and Gender Affirmation Model, as well as our prior mHealth research using mobile apps for HIV prevention and testing, we will design a gender-affirmative app-based intervention (entitled “Lakambini”) delivered by TW peer health educators, who will offer empowerment and gender-affirmative support to engage TW in HST and provide necessary counseling, referrals, and support in navigating services. Our first specific aim is to conduct iterative phases of qualitative research to inform gender-affirmative HST counseling, referrals, and navigation support protocols to be delivered via existing mobile app-based platforms for Filipina TW with high HIV risk. Our second specific aim is to examine the feasibility, acceptability, safety, and preliminary changes on HIV self-testing (primary outcome) as well as secondary outcomes: linkage to HIV prevention or care services; behavioral risk reduction; engagement in other medical, social, or community services for TW. We will conduct quantitative assessments at baseline, 3-month, and 6-month follow-ups. We will conduct qualitative exit interviews with participants to identify areas for further intervention improvement and identify methodological and design characteristics for a future RCT to address gender-minority stigma, gender affirmation, and HIV outcomes among TW in this setting. This R21 Exploratory/Developmental grant will thus provide the empirical foundation for a subsequent R-series application for a full RCT. Our approach builds on and extends our team’s collaborative experience working with gender and sexual minority communities in the Philippines, and will invest in capacity development for researchers and transgender HIV professionals and advocates in the Philippines.