Bictegravir/emtricitabine/tenofovir alafenamide ensures high rates of virological suppression maintenance despite previous resistance in PLWH who optimize treatment in clinical practice.

OBJECTIVES

We evaluated virological response and resistance profiles in individuals who were virologically suppressed who switched to bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF) in real life.

METHODS

Survival analysis was used to assess probability of virological rebound (VR). Cumulative major resistance mutations (MRM) and cumulative genotypic susceptibility score (cGSS) were evaluated before the switch.

RESULTS

Overall, 283 individuals virologically suppressed for a median (interquartile [IQR]) time of 7 (3-9) y were analyzed. Of these, 20.8% were in first-line treatment, 13.1% were highly treatment-experienced (HTE), and 8.5% had experienced previous integrase inhibitor (INI)-failures. Before the switch, nucleotide reverse transcriptase inhibitor NRTI MRM prevalence was 29% (M184V:13.8%; any thymidine analogue mutation: 14.1%; K65R: 0.7%; K70E 0.4%); only three (2.1%) individuals showed INI major resistance mutations (Y143C/H/R [n = 1]; Y143C [n = 1]; N155H [n = 1]), and 82.0% of individuals received fully active B/F/TAF. Ninety-six wk after switch, the probability of VR was 5%, with only 12 events of VR at a median (IQR) viremia level of 284 (187-980) copies/mL, mainly transient. No significant associations between virological outcomes and genotypic susceptibility to B/F/TAF were observed. People who experienced previous INI failures showed a significantly higher adjusted hazard ratio (AHR [95% CI]) to experience VR under B/F/TAF (3.9 [1.1-13.4], P = 0.031). This AHR increased in people who experienced INI failures and received partially active B/F/TAF (5.5 [1.4-21.1], P = 0.013).

CONCLUSION

Within 96 wk, a switch to B/F/TAF in individuals who were virologically suppressed ensured a very high rate of virological control in a clinical setting. Previous resistance alone did not affect B/F/TAF response. However, people who had previous INI failures were more prone to losing virological control under B/F/TAF.