Merck & Co. stock gains as efinopegdutide clears Phase 2b goal

Merck reported positive Phase 2b results for investigational efinopegdutide on Monday, November 9, 2026. In its company release, Merck said the investigational treatment met its primary endpoint in adults with metabolic dysfunction-associated steatohepatitis, or MASH, and stage F2 or F3 liver fibrosis.

Clinical data broaden Merck pipeline

The MK-6024-013 trial evaluated once-weekly efinopegdutide at 4, 7 and 10 milligrams against placebo, with an open-label semaglutide reference arm. After 52 weeks, MASH resolution without worsening of fibrosis occurred in 56 percent, 63 percent and 61 percent of participants across the three efinopegdutide doses, compared with 13 percent for placebo.

Fibrosis improvement of at least one stage without worsening of steatohepatitis reached 43 percent, 52 percent and 34 percent across the dose groups, versus 21 percent with placebo. The study enrolled 386 adults, while 92 percent of randomized participants completed treatment. The findings were presented at The Liver Meeting and published simultaneously in The Lancet.

Safety and development remain central

Merck described efinopegdutide as an investigational GLP-1 and glucagon receptor co-agonist with FDA Fast Track designation for MASH. The company said its safety profile was generally consistent with semaglutide, while discontinuations caused by adverse events ranged from 3 percent to 11 percent across the efinopegdutide groups, compared with 1 percent for both placebo and semaglutide.

Merck & Co. stock traded at 133.23 euros on Lang & Schwarz at 15:44 CET on Thursday, November 12, 2026, 1.38 percent above the Xetra close of Wednesday, November 11, 2026 at 131.42 euros. The quote was 1.25 percent above the 131.59 euros recorded in the previous report on Tuesday, November 10, at 18:46 CET.

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