Relationship between adherence to bictegravir/emtricitabine/tenofovir alafenamide fumarate and clinical outcomes in people with HIV in Japan: a claims database analysis

A lack of adherence to long-term antiretroviral therapy may impact viral suppression. The current study examined the relationship between medication adherence and clinical outcomes in people with human immunodeficiency virus infection (PWH) receiving bictegravir, emtricitabine, and tenofovir alafenamide fumarate (B/F/TAF). A retrospective cohort study using two Japanese claims databases was conducted. Adherence was measured by the proportion of days covered (PDC). Patients were grouped into 3 PDC category and persistence was estimated by Kaplan-Meier method. Cox regression analysis was performed to investigate whether the PDC was associated with treatment discontinuation. Among 952 patients, 820 (86.1%), 95 (10.0%), and 37 (3.9%) patients were grouped into the PDC >= 90%, 80- < 90%, and < 80% groups, respectively. Across all PDC groups, more than 90% of patients who received B/F/TAF were receiving treatment at 1 year. There was no significant difference in the risk of discontinuation between the lower PDC groups (80- < 90% and < 80%) and the PDC >= 90% group (0.400 [0.096, 1.661]; 2.244 [0.663, 7.594], hazard ratio [95% confidence interval], respectively). A drug resistance test was implemented for 15 patients, none of whom discontinued B/F/TAF after the test. The results suggest that events that could cause discontinuation, such as virologic failure, were not associated with PDC.