Long-acting injectable cabotegravir HIV PrEP uptake, adherence, and persistence in two large US integrated healthcare systems

Background: Long-acting cabotegravir (CAB-LA) was approved as HIV pre-exposure prophylaxis (PrEP) in the U.S. in December 2021, but data are limited on uptake, adherence, and persistence in clinical practice. Methods: We extracted electronic health records of adults receiving oral or injectable PrEP during December 2021-June 2024 at Kaiser Permanente (KP) Northern California and Mid-Atlantic States, two large integrated healthcare systems. We used chi-square tests to compare characteristics of CAB-LA users and oral-PrEP-only users. Among CAB-LA users, we assessed adherence to bimonthly injections after lead-in doses (weeks 0 and 4) and used Kaplan-Meier methods to estimate persistence. Results: Among 23,311 individuals accessing oral or injectable PrEP, 180 (0.8%) received CAB-LA, with 23.9% having no documentation of prior PrEP use at KP. Compared with oral-PrEP-only users, a lower proportion of CAB-LA users were commercially insured (82.2% vs 89.2%; P =0.014) and a higher proportion were Black (18.9% vs 10.2%) or Hispanic (34.4% vs 23.6%; P <0.001 across race/ethnicity categories). Of 688 non-lead-in CAB-LA injections, 90.4% were administered within 8 weeks +7 days after the prior injection. Persistence on CAB-LA was 87.9% and 74.9% at 6 and 12 months, respectively. There were no incident HIV infections during CAB-LA use. Conclusions: CAB-LA is engaging new users, including populations traditionally underrepresented in PrEP uptake, and adherence and persistence are high in clinical practice. However, uptake of CAB-LA is extremely low, suggesting population impact will be limited without efforts to expand implementation and use.