P429 Does HIV pre-exposure prophylaxis (PrEP) initiation in sexual health clinics impact subsequent HIV risk?

Background Since late 2016, the PrEP program in New York City’s 8 sexual health clinics (SHCs) has evolved from a model of active referral to external PrEP providers to on-site PrEP initiation (providing one month of PrEP and provider referral); this was implemented, clinic by clinic, over time. We hypothesized that HIV incidence would be lower for patients who received PrEP medication in SHCs. Methods We matched the following groups of men-who-have-sex-with-men (MSM) who received SHC PrEP services (12/2016-06/2017) to citywide HIV and STI registries: (1) same-day PrEP initiators, (2) referred-only for PrEP, (3) never-referred (not interested in starting PrEP). We calculated HIV incidence after SHC PrEP service date, using HIV surveillance data through 06/30/2018. We assessed factors associated with HIV diagnosis using Cox models that included initiation vs referred-only status, linkage, age, race/ethnicity, incident STI (chlamydia/gonorrhea/primary or secondary syphilis), and 3-month history of condomless receptive anal sex and number of sex partners. Results There were 267 initiators, 607 referred-only, and 96 never-referred patients; 40% of both initiated and referred-only patients linked to PrEP providers. Of all MSM (n=970; 1215 person-years [PY] of follow-up), 18 were newly diagnosed with HIV (median time to diagnosis 221 days; range 23-468). HIV incidence was 1.5/100PY (95%CI 0.9–2.3) and not significantly different by group: 1.8/100PY among initiators (linked: 1.6, non-linked: 2.0); 1.3/100PY referred-only (linked: 0.0, non-linked: 2.2); 1.8/100PY never-referred. HIV risk did not differ for initiators versus referred-only patients, but was higher among non-linked than linked (aHR 5.6; 95%CI 1.3–25.0) and those with STI versus no STI (aHR 10.1; 95%CI 2.3–44.7). Conclusion This examination of PrEP initiation in an episodic care setting did not find on-site PrEP provision to be associated with improved linkage and HIV outcomes. Understanding barriers to ongoing PrEP care is critical to improving linkage, and maximizing resources and the benefit of immediate PrEP access. Disclosure No significant relationships.