A NEW cohort study reveals that doxycycline postexposure prophylaxis (DoxyPEP) significantly reduces rates of bacterial sexually transmitted infections (STIs) among individuals using HIV preexposure prophylaxis (PrEP). This study, conducted within an integrated health system in California, offers critical insights into the real-world efficacy of DoxyPEP beyond clinical trials.
The study analyzed data from 11,551 adults prescribed HIV PrEP between 2022 and 2023, of whom 19.5% (2,253 individuals) were also dispensed DoxyPEP. Among recipients, the incidence of STIs decreased dramatically, including a 79% reduction in chlamydia, 80% in syphilis, and 12% in gonorrhea after starting DoxyPEP. Notably, declines were observed across specific infection sites, with urethral gonorrhea decreasing by 44% and rectal gonorrhea by 19%.
STI positivity among non-DoxyPEP users remained stable, reinforcing the direct impact of this intervention. DoxyPEP recipients were predominantly male (98.9%) and had a higher likelihood of prior STI diagnoses.
These findings underline DoxyPEP’s potential to address STI transmission at a population level, particularly when integrated with existing HIV prevention measures. However, further research is necessary to monitor long-term outcomes and address concerns regarding antimicrobial resistance.
This study offers promising data to support broader implementation of DoxyPEP, with substantial implications for public health strategies aimed at controlling STI outbreaks.
Reference: Traeger MW et al. Doxycycline Postexposure Prophylaxis and Bacterial Sexually Transmitted Infections Among Individuals Using HIV Preexposure Prophylaxis. JAMA Intern Med. 2025. doi:10.1001/jamainternmed.2024.7186.
