Impact of sex assigned at birth and HIV acquisition route on long-acting cabotegravir plus rilpivirine persistence: A real-world cohort study.

BACKGROUND

Despite growing adoption of long-acting antiretroviral therapy, real-world data on sex-related differences in treatment persistence remain limited.

METHODS

Retrospective single-center cohort study of virologically suppressed people with HIV (PWH) initiating long-acting cabotegravir plus rilpivirine (CAB + RPV LA) between September 2022 and September 2025 in Milan, Italy. Kaplan-Meier and Cox regression models, adjusted for confounders, assessed the association between sex assigned at birth (SAB), alone and jointly with HIV acquisition route, and treatment discontinuation.

RESULTS

Among 289 PWH (58 females, 20.1%), with a median follow-up of 28.8 months, 36 (12.4%) discontinued treatment. Female SAB was associated with higher discontinuation rates compared with male SAB (25.9% vs 9.1%) and independently predicted treatment discontinuation (adjusted hazard ratio [aHR] 2.56). Males who have sex with males (MSM) had a lower risk of discontinuation compared with heterosexual females (aHR 0.36), while no difference was observed between MSM and heterosexual males. Injection site reactions, logistical barriers, and pregnancy were the main reasons for discontinuation among females. Virological failure was uncommon overall (1%).

CONCLUSION

Female SAB was associated with higher CAB + RPV LA discontinuation rates, potentially reflecting a complex interplay of biological, reproductive, and socio-structural factors, supporting the need for sex- and gender-informed support strategies when initiating CAB + RPV LA.