Objective: To investigate the efficacy and safety of first-line antiretroviral treatment (ART) with 2DR dolutegravir/lamivudine (DTG/3TC) versus 3DR bictegravir/tenofovir alafenamide/emtricitabine (BIC/TAF/FTC) in persons with low CD4 cell counts and/or an AIDS-defining disease.
Design: Retrospective, multicentre, multinational study.
Methods: We conducted a retrospective, multicentre, multinational analysis to investigate the virological response and discontinuation rate in people living with HIV starting first-line ART with a CD4 cell count <200/μL and/or an AIDS-defining condition. Proportions of discontinuations were compared using univariate analysis. Virological response was analyzed using FDA snapshot analysis (HIV-1 RNA <50 copies/mL at week 48).
Results: Two hundred and fifty-nine people who were diagnosed late with HIV were included in the study. Sixty-nine of them were started on 2DR DTG/3TC and 190 on 3DR BIC/TAF/FTC. After matching 1 to 1 (matching criteria: age, sex, CD4 cell count, HI-viral load, Centers for Disease Control and Prevention (CDC) stage, n = 62 per group), the mean baseline CD4 cell count was 121/μL (standard deviation [SD] 65), including 21% presenting with an AIDS-defining condition. 96.2% and 91.8% of people living with HIV on 2DR and 3DR, respectively, had a viral load <50 copies/mL at week 48 (p = 0.244). No significant differences in discontinuation rates were observed at week 48 (5.5% in the 2DR and 9.4% in the 3DR group; p = 0.301).
Conclusion: In a European cohort of people diagnosed late with HIV who started first-line ART either with 2DR DTG/3TC or 3DR BIC/TAF/FTC, there were no significant differences in virological response and discontinuation rates after 48 weeks of treatment. With respect to the relatively small sample size and the inherent constraints of the study design, the possibility of establishing causal inference remains limited, and prospective studies are needed to further investigate on this topic.
Keywords: 2DR; 3DR; AIDS; HIV; bictegravir; dolutegravir; late diagnosis.
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