Used in immunotherapy research for modulating T-cell activity, particularly in autoimmune diseases and cancer. Targets the ICOS/ICOS-L pathway to suppress overactive immune responses. Investigated for treating conditions like rheumatoid arthritis, lupus, and other inflammatory disorders by blocking co-stimulatory signals that contribute to immune dysregulation. Also explored in combination with other immunotherapies to enhance anti-tumor responses while managing immune-related adverse effects.