Single tablet regimen with abacavir/lamivudine/dolutegravir compared with two-drug regimen with lamivudine and dolutegravir as different strategies of simplification from a multicenter HIV cohort study.

We investigated the effectiveness and safety of a dual therapy (DT) with lamivudine plus dolutegravir versus a single tablet regimen (STR) with abacavir/lamivudine/dolutegravir. We performed a retrospective analysis in a cohort of virologically suppressed HIV+ patients switching to lamivudine-dolutegravir or abacavir/lamivudine/dolutegravir. We evaluated the incidence of virological failure and treatment discontinuation, as well as their predictors. Non-parametric tests were applied to assess changes in immunological and metabolic parameters. In all, 616 patients were analyzed: 380 began STR and 236 DT. In the STR group three patients experienced VF; in the DT group seven patients experienced VF. No differences in cause of treatment discontinuation were found. The estimated probability of continuing therapy at 48 weeks were 88.5 % in DT and 90.3% in STR, without a statistically significant difference (Log-rank 0.338). Regarding the metabolic profile, in the STR group there was a reduction in LDL cholesterol levels at week 48 (p=0.008), whereas in the lamivudine group there was a significant reduction in total cholesterol level at week 48 (p=0.044). Regarding the renal function, in both groups we registered a reduction in estimated glomerular filtration rate (eGFR), with a median reduction of 8.4 ml/min in the STR group (p<0.001) and 10.2 mL/min in DT (p<0.001). We found a difference in strategy option: in a context of side effect and comorbidities, dual therapy strategy was preferred. Conversely, simplification and compliance improvement more frequently translated into a DTG-STR strategy.