Comparing the long-term effectiveness and safety of dolutegravir/lamivudine versus bictegravir/emtricitabine/tenofovir alafenamide fumarate as first-line regimens: a real life multicentre cohort.

Objectives: We compared the effectiveness and safety of bictegravir/emtricitabine/tenofovir alafenamide fumarate (BIC/FTC/TAF) and dolutegravir plus lamivudine (DTG + 3TC) in our cohort of treatment-naive people with HIV (PWH).

Methods: In a multicentre cohort of treatment-naive PWH starting a first-line regimen with either dolutegravir plus lamivudine or BIC/FTC/TAF, Kaplan-Meier survival analysis was used to estimate time to virological failure (VF) and time to treatment discontinuation (TD), whereas Cox regression was used to evaluate predictors of VF and TD. Changes in CD4+ cell count were assessed via non-parametric tests, and linear regression analyses were performed to explore predictors of CD4+ cell count changes.

Results: One hundred and seventy individuals were included: 66 started dolutegravir plus lamivudine (DTG group) and 104 started BIC/FTC/TAF (BIC group). During follow-up, we observed two VFs in the DTG group [1.7 per 100 person-years of follow-up (PYFU)] and two in the BIC group (1.7 per 100 PYFU). Estimated probability of remaining free from VF at Week 144 was 95.9% in the DTG group and 95.2% in the BIC group (log-rank P = 0.955). Four TDs were observed in the DTG group (3.4 per 100 PYFU) and 21 in the BIC group (17.6 per 100 PYFU). Estimated probability of maintaining the study regimen at Week 144 was 90.3% in the DTG group and 70.0% in the BIC group; individuals in the BIC group had a higher probability of TD (log-rank P = 0.003). In both groups, the CD4+ count improved significantly during follow-up.

Conclusions: Our study shows that both strategies are effective and safe, with few VFs and TDs due to tolerability issues.