Long-term outcomes of bictegravir/emtricitabine/tenofovir alafenamide as first-line therapy and as switch strategy in virologically suppressed persons with HIV: data from the ICONA cohort

Objectives: To assess the effectiveness of bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF) among people poorly represented in clinical trials and potentially at higher risk of suboptimal response to ART. Methods: Observational cohort study on persons with HIV (PWH) enrolled in ICONA who started BIC/FTC/TAF as initial therapy or as switching regimen while virologically suppressed. Primary endpoint was time to treatment failure (TF): new AIDS/death or virological failure (VF) or discontinuation for toxicity/failure. Secondary endpoints were time to treatment discontinuation for toxicity (TDT) and to VF. Groups of interest were those aged >50 years, female sex, and advanced HIV disease at first ART start. Probability of the events overall and according to groups and adjusted HR for every endpoint were calculated by Kaplan–Meier curves and Cox regression models. Results: Nine hundred and thirty-three ART-naive and 1655 ART-experienced PWH initiated BIC/FTC/TAF. Over a median follow-up of 69.8 weeks, 89 (9.6%) PWH at their first regimen experienced TF. PWH aged >50 years had 1.83-fold (95% CI: 1.19–2.83) higher risk of TF; PWH with advanced HIV disease had 2.21-fold (95% CI: 1.53–3.82) higher risk; there were no differences in TF according to sex. Over a median follow-up of 146.3 weeks, 109 (6.6%) out of 1655 switching PWH experienced TF; no differences were found in the risk of TF, TDT and VF according to groups of interest. Conclusions: Overall, BIC/FTC/TAF is well tolerated and virologically effective in the real-world scenario for ART-naive and -experienced PWH. Older ART-naive PWH and those with advanced HIV disease may respond less well as the burden of diseases might compromise treatment efficacy.