Merck has announced results from three phase 3 trials of its investigational, once-daily oral treatment combo, doravirine/islatravir (DOR/ISL), to treat adults living with HIV-1.
The phase 3 trials compared DOR/ISL to bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF) in adults who had not previously received antiretroviral treatment. The regimen was found to be non-inferior and to have a similar safety profile at week 28 to BIC/FTC/TAF.
The combo is the first non-integrase strand transfer inhibitor (INSTI) two-drug regimen to show such results. In addition, the regimen maintained virologic suppression at week 96 in patients who switched from other oral antiretroviral therapies.
Merck released the results as late-breaking data at the 33rd Conference on Retroviruses and Opportunistic Infections (CROI) 2026.