The single tablet, containing 100 mg doravirine and 0.25 mg islatravir, is for adults on a stable antiretroviral regimen with no history of virologic treatment failure and no known substitutions associated with resistance to doravirine.

Idvynso is contraindicated for use with drugs that are strong cytochrome P450 (CYP)3A enzyme inducers and lamivudine or emtricitabine.

The approval is based on data from two randomized, active-controlled, noninferiority trials. In the double-blind Trial 052, participants were randomly assigned to stay on Biktarvy (bictegravir/emtricitabine/tenofovir alafenamide; 171 individuals) or switch to Idvynso (342 individuals). Results showed that 1% of participants in both groups had a viral load of ≥50 copies/mL at 48 weeks.