Effectiveness and safety of tenofovir alafenamide/emtricitabine/bictegravir as a first-line regimen in people with HIV: A retrospective observational study

Objectives: To assess the effectiveness and safety of tenofovir alafenamide/emtricitabine/bictegravir (TAF/FTC/BIC) in patients newly diagnosed with HIV (PWH) in a non-experimental setting. Methods: We conducted a single-center, retrospective observational study that included all newly diagnosed PWH treated with TAF/FTC/BIC at our institution. Virological failure was defined as two consecutive HIV-RNA values of > 50 cp/ml after 48 weeks of treatment. Reasons for TAF/FTC/BIC interruption were also collected. The durability of TAF/FTC/BIC was estimated using Kaplan-Meier curves. Results: A total of 236 PWH started TAF/FTC/BIC, with a median follow-up time of 13 months (interquartile range [IQR] 4-27 months). Most PWH were cisgender men (178/236, 75.4%) with a median age at diagnosis of 37 years (IQR 29-48) and a median cluster of differentiation 4 cell counts of 302 cells/mm3 (IQR 117-467). One protocol-defined virological failure was observed, without the development of drug resistance, resulting in an incidence of 3.1 per 1000 person-years of follow-up (95% confidence interval [CI] 0.8-17.3). Six (2.5%) PWH discontinued TAF/FTC/BIC because of toxicity. The estimated durabilities of TAF/FTC/BIC at 12 and 24 months were 84.8% (95% CI 78.6-89.3%) and 75.5% (95% CI 67.6-82.6%), respectively. Conclusions: In our cohort of newly diagnosed PWH treated with TAF/FTC/BIC, the low occurrence of virological failure and discontinuation related to drug toxicities underscores the effectiveness and tolerability of the regimen.