Merck and Gilead reported positive phase 3 results for a weekly oral HIV regimen combining islatravir and lenacapavir, with both studies meeting their primary efficacy endpoints. The companies said the combination was non-inferior in patients switching from Gilead’s once-daily Biktarvy and performed as expected when patients switched off standard-of-care antiretrovirals. Safety was also a key focus: Merck and Gilead reported no new safety concerns in either Islend-1 or Islend-2. The companies plan to submit the data to regulators worldwide and present at an upcoming scientific congress. Commercially, the results intensify competition in long-acting and convenience-focused HIV therapy, even as analysts continue to view Biktarvy’s established efficacy as a benchmark. The next step will be how regulators evaluate long-term safety and resistance potential for a once-weekly regimen.