Merck & Co. Inc. has announced that the U.S. Food and Drug Administration (FDA) has accepted the New Drug Application (NDA) for its investigational HIV treatment, doravirine/islatravir (DOR/ISL). This once-daily, oral, two-drug regimen is designed for adults with HIV-1 infection who are virologically suppressed on antiretroviral therapy. The FDA has set a target action date of April 28, 2026, under the Prescription Drug User Fee Act. If approved, DOR/ISL would be the first FDA-approved two-drug regimen without an integrase inhibitor, offering a non-inferior efficacy and safety profile compared to current three-drug regimens. The NDA is supported by data from two Phase 3 clinical trials demonstrating its effectiveness and safety.