Merck & Co (NYSE: MRK) presented initial results from a Phase 2b trial evaluating tulisokibart at the European Academy of Dermatology and Venereology (EADV) 2026 Congress. The study focused on patients with moderate to severe hidradenitis suppurativa.
The trial met its primary endpoint of Hidradenitis Suppurativa Clinical Response 50 (HiSCR50) at week 16. In the high-dose group (480 mg Q2W, n=42), 72% of patients achieved the response, compared to 64% in the medium-dose group (480 mg Q4W, n=42). These figures represented improvements of 37% and 29% over the placebo group (35%, n=44), respectively. An exploratory analysis showed that low-dose participants (240 mg Q4W, n=21) achieved a 52% response rate, exceeding the placebo group by 17%.
Secondary endpoints at week 16 indicated numerical improvements across active doses. HiSCR75 response rates were 41% for high-dose patients, 40% for medium-dose patients, and 29% for low-dose patients, compared to 15% for placebo. Quality of life improvements were also observed, with high-dose patients recording a mean Dermatology Life Quality Index reduction of -5.62 from baseline, a 3.16-point advantage over placebo. Medium-dose participants recorded a reduction of -3.50, a gain of 1.02 points over placebo.
The safety profile of tulisokibart was comparable to placebo. Adverse events affected 42.9% of high-dose patients, 47.6% of medium-dose patients, and 52.4% of low-dose patients, compared to 40.9% in the placebo arm. Serious adverse events were low across groups, ranging from 2.4% to 4.8% versus 2.3% for placebo, with no serious or opportunistic infections reported.
Tulisokibart is an investigational monoclonal antibody targeting tumor necrosis factor-like cytokine 1A (TL1A). The company noted that tulisokibart features the broadest anti-TL1A development program, spanning six disease indications, including Phase 3 trials in ulcerative colitis and Crohn’s disease.
