Pre-Exposure Prophylaxis for the Prevention of HIV-1: An Assessment of Oral Pre-Exposure Prophylaxis Usage Patterns, First Evidence of HIV-1, and HIV-1 Risk Factors in the United States

In clinical trials, once-daily oral tenofovir-based pre-exposure prophylaxis (PrEP) significantly reduced HIV-1 acquisition risk; however, this was highly dependent on medication adherence and persistence. We report clinical characteristics, PrEP usage patterns, first evidence of HIV-1, and associated risk factors among adults with commercial insurance using oral PrEP in the United States using health plan claims from the IQVIA PharMetrics® Plus database between January 1, 2015, and March 31, 2020, from individuals who newly initiated emtricitabine/tenofovir disoproxil fumarate (FTC/TDF) or FTC/tenofovir alafenamide (TAF) for daily PrEP. Overall, 25,419 individuals were included (FTC/TDF, <i>n</i> = 24,232; FTC/TAF, <i>n</i> = 1187), with generally similar characteristics reported during the 6-month baseline period across cohorts. Mean follow-up length was 504 and 77 days for FTC/TDF and FTC/TAF, respectively, corresponding with the 2019 approval of FTC/TAF for PrEP. Similarly, mean PrEP use duration was 354 and 68 days for FTC/TDF and FTC/TAF, respectively. PrEP breaks (>90-day gap) were observed in 11.1% of individuals using FTC/TDF, with a mean break duration of 249 days; 20.0% of individuals using FTC/TDF and 7.3% using FTC/TAF had ≥1 sexually transmitted infection diagnosis during follow-up. From 6 to 12 months of follow-up, mean FTC/TDF proportion of days covered (PDC; 0.74 vs. 0.67) and persistence (70.2% vs. 57.4%) decreased; real-world PDC and persistence were lower than reported in globally conducted clinical trials. First evidence of HIV-1 was infrequent among individuals using FTC/TDF (0.6%), though 60.3% had PrEP on hand when HIV-1 definition was met; high-risk sexual behavior, syphilis, and gonorrhea were the most important risk factors.