The FDA approved Merck’s once-daily HIV regimen Idvynso, adding a two-drug option for adults with HIV-1 who are virologically suppressed. The approval comes as Merck targets a market long dominated by other combination regimens and highlights continued regulatory momentum in HIV therapeutics. The decision also sets up direct competitive pressure on established anchor therapies, particularly where safety or tolerability can drive switching decisions. For developers and clinicians, the approval matters as it provides a new formulation and dosing strategy within current antiretroviral frameworks, potentially affecting payer and guideline choices.