07:30 AM EDT, 10/06/2025 (MT Newswires) -- Merck ( MRK ) said Monday it has begun three phase 2 trials to evaluate its experimental therapy, tulisokibart, in patients with hidradenitis suppurativa, axial spondyloarthritis, and rheumatoid arthritis.

The company said the global studies would enroll more than 640 patients.

Merck ( MRK ) added that tulisokibart is now being tested in six immune-mediated diseases, including ongoing phase 3 trials in ulcerative colitis and Crohn's disease, as well as a phase 2 trial in systemic sclerosis-associated interstitial lung disease.