The FDA approved Merck’s once-daily HIV regimen Idvynso (doravirine/islatravir), giving clinicians a new option for adults with HIV-1 infection who are virologically suppressed and have no known resistance substitutions. The approval arrives ahead of an April 28 PDUFA date, per the company’s update. The approval adds to Merck’s attempt to reassert competitive positioning in HIV, an area many biotechs have deprioritized. Clinicians will look at how the new combination performs versus existing once-daily options in real-world persistence and resistance development. For developers, the decision also keeps islatravir in focus after years of regulatory scrutiny across the class, though specifics on label restrictions and patient selection will matter for adoption.