Efficacy and safety of dolutegravir plus emtricitabine vs combined antiretroviral therapy for the maintenance of HIV suppression: results through week 144 of the SIMPL’HIV trial. Open Forum Infectious Diseases
The SIMPL’HIV study investigated whether switching to dolutegravir (DTG) + emtricitabine (FTC) was noninferior to continuing combined antiretroviral therapy for maintaining HIV-1 suppression. The study found that switching to DTG + FTC was indeed non-inferior to continuing cART, with around 91% of participants maintaining HIV-1 RNA levels <50 copies/mL at week 48 and no confirmed virologic failures in the DTG + FTC group. Here, Marinosci et al. present long-term results from the 144-week analyses of the SIMPL’HIV study.
In the ITT analysis at week 144, 87.1% of participants initially assigned to DTG + FTC group and 81.9% of those initially randomized to the cART group maintained HIV-1 RNA levels <100 copies/mL, demonstrating comparable efficacy (adjusted difference, 5.2%; 95% CI, −5.3% to 15.4%). According to the FDA algorithm, 86% of participants in the DTG + FTC group and 79.8% of patients in the cART group had HIV-1 RNA <50 copies/mL at week 144 (adjusted difference, 6.2%; 95% CI, −4.7% to 16.8%). One patient in the DTG + FTC group and 4 in the cART group had HIV-1 RNA levels >50 copies/mL at week 144. Moreover, the study demonstrated that CD4 gains, adverse events, quality of life, and patient satisfaction were comparable between groups.
In conclusion, the SIMPL’HIV study supports DTG + FTC as an effective and durable maintenance therapy for HIV-1 infection and demonstrates comparable efficacy to 3-drug regimens. FTC shares similarities with 3TC in terms of convenience, safety, and resistance profile. However, FTC boasts a longer intracellular half-life and demonstrates greater in vitro potency, rendering it a favorable choice for the SIMPL’HIV trial at the time the protocol was written in 2016. However, the commercialization of a co-formulated version of DTG/3TC in 2019 made a DTG + FTC regimen a less favorable option.