Doxycycline Post-exposure Prophylaxis Awareness and Use Among Transgender Women in San Francisco, 2023-2024: Assessment One Year After Release of Health Department Guidance.

The San Francisco health department released guidelines on doxycycline post-exposure prophylaxis (doxy-PEP) for sexually transmitted infection (STI) prevention in October 2022. Guidelines recommended doxy-PEP for transgender women (hereafter trans women) and men who have sex with men with a history of bacterial STI and condomless anal or oral sex in the last year. We assessed doxy-PEP awareness and use among trans women in San Francisco using National HIV Behavioral Surveillance (NHBS) data from July 2023-May 2024, spanning 9-19 months after guideline release. In-person interviews recorded demographics, behaviors, HIV serostatus, STI history, and doxy-PEP awareness, discussion with a provider, and use in the last year. Among 339 trans women surveyed, 37% were aware of doxy-PEP. In the last year, 20% discussed doxy-PEP with a provider and 11% used doxy-PEP. Among trans women not living with HIV, awareness was correlated with age under 50 years (AOR 3.86, CI 1.92-7.74), engaging in sex work (AOR 1.85, 95% CI 1.02-3.38), and testing positive for a bacterial STI (AOR 2.92, 95% CI 1.35-6.33). Among those living with HIV, awareness of doxy-PEP was correlated with testing positive for an STI (OR 3.05, 95% CI 1.22-7.64). Despite efficacy demonstrated for trans women in clinical trials and health department guidelines prioritizing doxy-PEP for trans women, awareness of this effective STI prevention method was low. These findings mirror the experience with HIV PrEP roll-out for trans women. Targeted interventions and differentiated delivery models are needed to improve access, engagement, and uptake in this population.