Abstract
OBJECTIVE: Dolutegravir plus lamivudine (2-DR) is suggested as an initial and switch option in HIV-1 treatment. The aim of this study was to analyze the effectiveness, durability, and safety of 2-DR compared to bictegravir/emtricitabine/tenofovir alafenamide (3-DR). PATIENTS AND METHODS: This was an observational, ambispective study that included all treatment-naïve (TN) and treatment-experienced (TE) people living with HIV/AIDS (PLWH), who started 2-DR or 3-DR between 01 July 2018, and 31 January 2022. The primary endpoint was non-inferiority, at 24 and 48 weeks, of 2-DR vs 3-DR regarding the percentage of PLWH with viral load (VL)<50 and 200 copies/mL in TN (12% margin) and VL≥50 and 200 copies/mL in TE (4% margin). Durability of response and safety were also measured. RESULTS: 292 PLWH were included (39 TN and 253 TE). In TN PLWH, non-inferiority was not achieved at 24 weeks (17; 95% CI -17 to 51 p = 0.348). By week 48, all PLWH on 3-DR maintained VL<50 copies/mL compared to 70% of PLWH on 2-DR although without reaching statistical significance (-33; 95% CI -60 to -10 p = 0.289). Non-inferiority was not achieved in TE PLWH either at 24 (0.4; 95% CI -9 to 10 p = 1) or at 48 weeks (4.5; 95% CI -0.5 to 9 p = 0.132). In TN, the risk of treatment discontinuation was similar between groups (HR: 0.31, p = 0.07); similar rates were also found in TE (HR: 1.3, p = 0.38). TE PLWH on 2-DR showed a better safety profile compared to 3-DR (p = 0.017). CONCLUSION: Our results did not show non-inferiority in terms of virological effectiveness. Additionally, durability and safety of 2-DR were confirmed to be similar to 3-DR.