Merck announced positive topline results from a pivotal Phase 3 trial evaluating its once-daily, oral two-drug regimen doravirine/islatravir (DOR/ISL) in treatment-naïve adults with HIV-1. The regimen met the primary efficacy endpoint, demonstrating non-inferiority to the standard three-drug regimen bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF), with similar rates of viral suppression at Week 48. The safety profile of DOR/ISL was also comparable.
Merck plans to present full results at an upcoming scientific meeting and submit the data to global regulators. The FDA has already accepted the company’s New Drug Application for DOR/ISL as a treatment option for virologically suppressed adults seeking to switch regimens, with a target decision date of April 28, 2026.
Dr. Eliav Barr said the findings highlight the potential of DOR/ISL as the first non–integrase inhibitor two-drug regimen to show non-inferiority to a leading INSTI-based therapy.