The FDA approved Merck’s Idvynso (doravirine/islatravir), a two-drug regimen for adults with HIV-1 who are virologically suppressed, expanding treatment options beyond Gilead’s Biktarvy. The approval is for patients with no prior virologic failure and no known resistance substitutions related to doravirine. The label adds direct competition in a segment where many patients start on integrase- or backbone-based regimens. Merck’s strategy also underscores continued focus on simpler oral options that can help drive switching decisions tied to safety and tolerability. From an industry perspective, Idvynso’s clearance adds another differentiated mechanism-of-action combination to the crowded “switch” market, where payer coverage and real-world persistence can determine uptake.