Clinical outcomes on B/F/TAF and dolutegravir-based regimens at 12 months following regimen switch: an observational cohort study.

Background: This retrospective observational study evaluated the clinical use and treatment outcomes in virologically suppressed people with HIV (PWH) switching to either bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF) or dolutegravir (DTG)-based regimens (single- and multi-tablet formulations (STR and MTR)).

Methods: We analyzed electronic medical and dispensing records from Trio Health HIV Research Network for treatment-experienced PWH ≥ 18 years suppressed (viral load [VL] < 200 copies/mL) at switch to B/F/TAF, DTG STR (DTG/3TC, DTG/RPV, DTG/3TC/ABC) or most common DTG MTRs with VL at 12 months (+/-3) since switch between April 2019 and December 2024. Univariate comparisons: chi-square or t-test; characteristics associated with virologic suppression at 12 months: multivariable logistic regression [LR], controlling for age, gender, race, baseline CD4 count, regimen, and adherence (proportion days covered [PDC] ≥ 80%).

Results: Of 3141 PWH, 66% switched to B/F/TAF, 27% to DTG STR, and 7% to DTG MTRs. Baseline characteristics differed significantly between groups: B/F/TAF group had a higher proportion of males (81% vs. 67% DTG MTR) and Black individuals (40% vs. 31% DTG STR), while the DTG STR and MTR groups had higher proportions of PWH with cardiovascular disease (35% and 39% respectively vs. 32% on B/F/TAF) and eGFR < 60 mL/min/1.73 m² (18% and 22% respectively vs. 8% on B/F/TAF). At 12 months post switch, proportion of individuals with PDC ≥ 80% was higher in the DTG STR group (76%) compared to DTG MTR (67%) and B/F/TAF (69%) with similar virologic suppression across groups (98%, 98%, and 97% respectively). In multivariable LR, there was an association of White race, PDC ≥ 80%, and CD4 ≥ 200 cells/mm³ with greater probability of suppression at 12 months.

Conclusions: Despite differences in baseline characteristics and regimen adherence between individuals switched to B/F/TAF, DTG STRs, and MTRs, both B/F/TAF and DTG-based regimens were associated with high rates of virologic suppression. This data strongly supports the inclusion of these simple and safe regimens as switch options in virologically suppressed PWH. Baseline differences in patient demographics and characteristics may have impacted the adherence on B/F/TAF compared to DTG STR, however virologic outcomes were preserved, demonstrating the forgiveness of B/F/TAF in populations potentially facing adherence challenges.