Merck (MRK) stock swings, ends flat after FDA clears Keytruda regimen in ovarian cancer
New York, Feb 12, 2026, 16:23 EST — After-hours Merck & Co finished almost flat on Thursday, wiping out earlier gains, after the FDA signed off on a Keytruda combo for certain patients with platinum-resistant ovarian cancer—a form that recurs within six months after platinum chemo. Shares slipped 0.03% to $119.28, swinging between $118.18 and $121.62 over the session.