Merck & Co. presented initial results from its Phase 2b MK-7240-012 trial of tulisokibart in patients with moderate to severe hidradenitis suppurativa at the European Academy of Dermatology and Venereology 2026 Congress. The investigational monoclonal antibody targeting tumor necrosis factor-like cytokine 1A met the study's primary endpoint, with HiSCR50 responses at week 16 of 72% for the 480 mg every-two-weeks regimen and 64% for 480 mg every-four-weeks, versus 35% for placebo. The low-dose 240 mg every-four-weeks group recorded a 52% response rate in an exploratory analysis. HiSCR75 and quality-of-life results also numerically favored some active regimens, while adverse events and serious adverse events were broadly comparable with placebo and no serious or opportunistic infections were reported. Tulisokibart's development program spans six disease indications, including Phase 3 trials in ulcerative colitis and Crohn's disease. Merck shares were down 1.63% at $146.85 at publication, according to Benzinga Pro data.