CROI 2025 Abstract eBook

Abstract eBook

Poster Abstracts

was negatively associated to unknown HIV status and higher internalized LGBTQIAPN+. Among those reporting HIV negative/unknown status, doxy-PEP awareness was higher among those who ever used PrEP vs. never (59.3% vs. 40.7%; p<0.001). Only 5.6% (n=279) reported previous doxy-PEP use, with the majority (64.2%) having received it through a healthcare professional. Conclusions: Doxy-PEP awareness among SGM in Brazil remains limited, reflecting the absence of implementation studies and official guidelines in the country. Tailored efforts are crucial to raise awareness, especially among populations with lower education levels, limited HIV knowledge, and those less engaged with existing prevention services. Strengthening awareness campaigns and integrating doxy-PEP into broader sexual health programs will be key to ensuring equitable access, reducing bacterial STI incidence and addressing the underlying social determinants of health.

an important demographic for scale-up of doxy-PEP. Given the relative cost of treating syphilis and other STIs to the prevention of syphilis, it would be prudent for public health departments across the United States to share in the prioritization of syphilis prevention among YBSMM, especially those who are interested in it. 1281 Increased Knowledge and Use of Doxycycline Postexposure Prophylaxis in King County, Washington Jennifer E. Balkus 1 , Courtney Moreno 1 , Francis Slaughter 2 , Karen Chung 1 , Chase Cannon 2 , Tim W. Menza 2 , Matthew Golden 2 , Sara Glick 2 1 Public Health–Seattle & King County, Seattle, WA, USA, 2 University of Washington, Seattle, WA, USA Background: Following evidence of doxycycline postexposure prophylaxis (doxyPEP) efficacy to prevent chlamydia, gonorrhea and syphilis among men and transgender women who have sex with men, Public Health – Seattle & King County (PHSKC) released provider guidance in June 2023. We utilized data from PHSKC’s annual Pride Survey to assess changes in knowledge and self-reported doxyPEP use among sexually active respondents from King County in the year after release of local guidelines. Methods: The Pride Survey is an annual, cross-sectional, online, anonymous, sexual health survey open to Washington residents who identify as LGTBQ+. The survey is advertised at Pride events and through social media, local LGBTQ+ news sources, and posters at LGBTQ+ venues in the greater Seattle area throughout the summer. Among the subset of respondents from King County, we used descriptive statistics to compare doxyPEP knowledge, interest, and use in 2023 versus 2024 among transgender women and gay, bisexual, and other men who have sex with men (GBMSM) who reported sex with a male identifying partner in the past year. Given the historic and ongoing impacts of structural racism on healthcare access and engagement, we also assessed doxyPEP knowledge and use by self-reported race and ethnicity among 2024 survey respondents. Results: A total of 232 respondents in 2023 and 287 in 2024 were included in this analysis. Respondent characteristics were similar between years; when aggregated across years: 91% were HIV-negative, 45% were currently using PrEP and 14% reported an STI in the past year. Knowledge of doxyPEP, self reported use and interest in use among those who had not reported doxyPEP in the last 12 months are presented by year in the Table. DoxyPEP knowledge and use increased, especially among GBMSM using PrEP; knowledge of doxyPEP was lower among trans women compared to GBMSM. DoxyPEP knowledge, use and interest was qualitatively similar by self-reported race and ethnicity. Nearly all (90%) respondents reported getting doxyPEP from their healthcare provider. Conclusions: Among King County Pride Survey respondents, knowledge and use of doxyPEP use increased among GBMSM from 2023 to 2024, with the highest knowledge and use among GBMSM using PrEP. Knowledge of doxyPEP was lower among 2024 respondents who identified as transgender women, representing an important opportunity for both community and provider education to improve knowledge of and access to doxyPEP in this priority population.

Poster Abstracts

1280 Young Black Sexually Minoritized Men Living With HIV, Substance Use, and Syphilis Want Doxy-PEP Jade Pagkas-Bather 1 , Ella Wiger 1 , Ellen Almirol 2 , Justin Knox 3 , Yen-Tyng Chen 4 , Dustin Duncan 3 , John Schneider 1 1 University of Chicago, Chicago, IL, USA, 2 University of Chicago Medical Center, Chicago, IL, USA, 3 Columbia University Irving Medical Center, New York, NY, USA, 4 Rutgers University, Piscataway, NJ, USA Background: Doxycycline post-exposure prophylaxis (doxy-PEP) offers a cheap and effective method for pharmacologic syphilis and chlamydia prevention among men who have sex with men but is underutilized by populations most in need. While syphilis can be easily treated and prevented, young Black sexually minoritized men (YBSMM) in the United States continue to bear the brunt of new infections. This study examined factors associated with syphilis acquisition and doxy-PEP interest among an HIV status-neutral cohort of YBSMM. Methods: The N2 (Networks and Neighborhoods) Phase 2 cohort included YBSMM aged 16-34 years, identifying as Black, assigned male at birth, who reported at least 1 sexual encounter with a cisgender man or transgender woman in the past 12 months. Our primary outcome was defined as active syphilis with a titer of 1:8 or greater. Generalized linear models were fit to calculate the unadjusted and adjusted relative risks between participants with and without active syphilis based on demographics, health factors, substance use, and doxy-PEP interest. Results: 468 participants were included in the analysis and 25.6% had active syphilis. Participants with active syphilis were older (28.7 years, SD 3.6 vs. 27.6 years, SD 3.8, p<0.01) and had an increased HIV prevalence (81.7% vs. 46.0%, p<0.01). A higher proportion of those with active syphilis were interested in doxy-PEP to prevent syphilis (75.5% vs. 54.7%, p<0.01) and reported methamphetamine use in the past year (26.7% vs. 8.9%, p<0.01) compared to those without active syphilis. In the adjusted models, the risk of having active syphilis among those living with HIV was 2.88 times higher (95% CI: 1.83, 4.53, p<0.01), and methamphetamine use was associated with a 95% increased risk of active syphilis among YBSMM (RR 1.95, 95% CI: 1.43, 2.66, p<0.01) compared to those who did not report methamphetamine use. Interest in doxy-PEP was also positively associated with active syphilis (RR 1.55, 95% CI 1.04, 2.32, p=0.03). Conclusions: YBSMM who are living with HIV and/or syphilis, and those that use methamphetamine and are interested in utilization of doxy-PEP represent

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