Dolutegravir-Based or Low-Dose Efavirenz-Based Regimen for the Treatment of HIV-1.

BACKGROUND

An efavirenz-based regimen (with a 600-mg dose of efavirenz, known as EFV600) was the World Health Organization preferred first-line treatment for human immunodeficiency virus type 1 (HIV-1) infection until June 2018. Given concerns about side effects, dolutegravir-based and low-dose efavirenz-based combinations have been considered as first-line treatments for HIV-1 in resource-limited settings.

METHODS

We conducted an open-label, multicenter, randomized, phase 3 noninferiority trial in Cameroon. Adults with HIV-1 infection who had not received antiretroviral therapy and had an HIV-1 RNA level (viral load) of at least 1000 copies per milliliter were randomly assigned to receive either dolutegravir or the reference treatment of low-dose efavirenz (a 400-mg dose, known as EFV400), combined with tenofovir and lamivudine. The primary end point was the proportion of participants with a viral load of less than 50 copies per milliliter at week 48, on the basis of the Food and Drug Administration snapshot algorithm. The difference between treatment groups was calculated, and noninferiority was tested with a margin of 10 percentage points.

RESULTS

A total of 613 participants received at least one dose of the assigned regimen. At week 48, a viral load of less than 50 copies per milliliter was observed in 231 of 310 participants (74.5%) in the dolutegravir group and in 209 of 303 participants (69.0%) in the EFV400 group, with a difference of 5.5 percentage points (95% confidence interval [CI], -1.6 to 12.7; P<0.001 for noninferiority). Among those with a baseline viral load of at least 100,000 copies per milliliter, a viral load of less than 50 copies per milliliter was observed in 137 of 207 participants (66.2%) in the dolutegravir group and in 123 of 200 participants (61.5%) in the EFV400 group, with a difference of 4.7 percentage points (95% CI, -4.6 to 14.0). Virologic failure (a viral load of >1000 copies per milliliter) was observed in 3 participants in the dolutegravir group (with none acquiring drug-resistance mutations) and in 16 participants in the EFV400 group. More weight gain was observed in the dolutegravir group than in the EFV400 group (median weight gain, 5.0 kg vs. 3.0 kg; incidence of obesity, 12.3% vs. 5.4%).

CONCLUSIONS

In HIV-1-infected adults in Cameroon, a dolutegravir-based regimen was noninferior to an EFV400-based reference regimen with regard to viral suppression at week 48. Among participants who had a viral load of at least 100,000 copies per milliliter when antiretroviral therapy was initiated, fewer participants than expected had viral suppression. (Funded by Unitaid and the French National Agency for AIDS Research; NAMSAL ANRS 12313 ClinicalTrials.gov number, NCT02777229.).