A Clinical Study of Tulisokibart (MK-7240) to Treat Radiographic Axial Spondyloarthritis (MK-7240-013)

Researchers are looking for new ways to treat radiographic axial spondyloarthritis (r-axSpA). R-axSpA is a type of arthritis that causes pain, stiffness, and inflammation (swelling) in the spine and joints in the pelvis (hip bone). Radiographic means the damage it causes can be seen on X-rays. This study will help find out if a study medicine called tulisokibart can treat symptoms of r-axSpA. Researchers will look at different doses of tulisokibart. Researchers want to know if at least one of the study doses of tulisokibart works better than a placebo to improve r-axSpA symptoms. A placebo looks like the study medicine but has no study medicine in it. Using a placebo helps researchers better understand the effects of the study medicine.

Inclusion Criteria: The main inclusion criteria include but are not limited to the following: * Has a clinical diagnosis of axial spondyloarthritis (axSpA) and meets the Assessment of SpondyloArthritis international Society (ASAS) classification criteria for axSpA including ≥3 months of back pain with age at symptom onset \