Used in the treatment of autoimmune diseases such as systemic lupus erythematosus (SLE) and lupus nephritis. Targets ICOS (inducible T-cell co-stimulator) on activated T cells, helping to modulate immune response and reduce disease activity. Clinical trials have evaluated its safety and efficacy in suppressing abnormal immune activation in patients with moderate to severe SLE, showing potential for improving clinical outcomes with an acceptable safety profile.