Racial/Ethnic and HIV risk category disparities in PrEP discontinuation among patients in publicly-funded primary care clinics.

OBJECTIVE Dissemination of pre-Exposure Prophylaxis (PrEP) is a priority for reducing new HIV infections, especially among vulnerable populations. However, there are limited data available on PrEP discontinuation following initiation, an important component of the PrEP cascade. DESIGN Patients receiving PrEP within the San Francisco Department of Public Health Primary Care Clinics (SFPCC) are included in a PrEP registry if they received a PrEP prescription, were not receiving post-exposure prophylaxis, and not known to be HIV positive. METHODS We calculated PrEP discontinuation for patients initiating PrEP at any time from January 2012 to July 2017 and evaluated their association with demographic and risk variables using Cox regression analysis. RESULTS Overall, 348 patients received PrEP over the evaluation period. The majority (84%) were men, and the cohort was racially/ethnically diverse. The median duration of PrEP use was 8.3 months. In adjusted analysis, PrEP discontinuation was lower among older patients (aHR 0.89; 95% CI: 0.80-0.99; p = 0.03); but higher among Black patients (compared with White patients) (aHR 1.87; 95%CI: 1.27-2.74; p = 0.001), patients who inject drugs (aHR 4.80; 95%CI 2.66-8.67; p < 0.001), and transgender women who have sex with men (compared with men who have sex with men) (aHR 1.94; 95%CI: 1.36-2.77; p < 0.001). CONCLUSION Age, racial/ethnic, and risk category disparities in PrEP discontinuation were identified among patients in a public-health funded primary care setting. Further efforts are needed to understand and address PrEP discontinuation among priority populations to maximize the preventive impact of PrEP, and reverse HIV-related disparities at a population level.