Efficacy and safety of doravirine/islatravir in heavily treatment-experienced participants living with HIV-1: results from a randomized trial

OBJECTIVE: This study evaluated the efficacy (day 8) and safety (week 49) of doravirine/islatravir (DOR/ISL; 100 mg/0.75 mg) plus baseline antiretroviral therapy (ART) and optimized background therapy (OBT) in heavily treatment-experienced (HTE) adults living with detectable HIV-1 RNA. DESIGN AND METHODS: HTE adults with confirmed plasma viral load more than 500 copies/ml receiving a stable ART regimen for at least 3 months were randomly assigned 1 : 2 : 1 : 1 to receive once-daily ISL alone, DOR alone, DOR/ISL, or matching placebo for 7 days; at day 8, baseline ART was optimized and all participants received DOR/ISL and OBT through week 49. The primary efficacy endpoint was percentage of participants receiving DOR/ISL achieving at least 0.5 log 10 decline in viral load from baseline (day 1) to day 8. Secondary efficacy endpoints included HIV-1 RNA levels and CD4 + T-cell counts through week 49. RESULTS: Thirty-five of the planned 100 participants were enrolled; most were White (57.1%) and men (77.1%) with median age of 50 years. From days 1 to 8, an at least 1.0 log 10 decrease in HIV-1 RNA was achieved in 85.7% of the DOR/ISL group compared with 0 in the placebo group. At week 49, HIV-1 RNA less than 50 copies/ml was achieved in 22 participants (71%) and the mean increase in CD4 + T-cell count was 87 cells/μl. Adverse events were reported in 29 participants (82.9%) through week 49; 9 (25.7%) were considered related to DOR/ISL. CONCLUSION: DOR/ISL plus OBT improved HIV-1 suppression in HTE adults living with HIV-1 and was generally well tolerated. CLINICALTRIALSGOV: NCT04233216.