Effectiveness of double-dose dolutegravir in people receiving rifampin-based tuberculosis treatment: an observational, cohort study of people with HIV from six countries.

Background: Tenofovir-lamivudine-dolutegravir (TLD) is the preferred first-line antiretroviral therapy (ART) regimen. An additional 50 mg dose of dolutegravir (TLD + 50) is required with rifampin-containing tuberculosis (TB) co-treatment. There are limited data on the effectiveness of TLD + 50 in individuals with TB/HIV.

Methods: Prospective, observational cohort study at 12 sites in Haiti, Kenya, Malawi, South Africa, Uganda, Zimbabwe. Participants starting TLD and rifampin-containing TB treatment were eligible. Primary outcome was HIV-1 RNA ≤1000 copies/mL at end of TB treatment.

Findings: We enrolled 91 participants with TB/HIV: 75 (82%) ART-naïve participants starting TLD after a median 15 days on TB treatment, 10 (11%) ART-naïve participants starting TLD and TB treatment, 5 (5%) starting TB treatment after a median 3.3 years on TLD, and 1 (1%) starting TB treatment and TLD after changing from efavirenz/lamivudine/tenofovir. Median age was 37 years, 35% female, median CD4 count 120 cells/mm3 (IQR 50-295), 87% had HIV-1 RNA >1000 copies/mL. Two participants died during TB treatment. Among 89 surviving participants, 80 were followed to TB treatment completion, including 7 who had no HIV-1 RNA result due to missed visits. Primary virologic outcome was assessed in 73 participants, of whom 69 (95%, 95% CI 89-100%) had HIV-1 RNA ≤1000 copies/mL. No dolutegravir resistance mutations were detected among four participants with HIV-1 RNA >1000 copies/mL.

Interpretation: In routine programmatic settings, concurrent rifampin-containing TB treatment and TLD + 50 was feasible, well-tolerated, and achieved high rates of viral suppression in a cohort of predominantly ART-naïve people with TB/HIV.