Biologic Therapy for Refractory Immune Checkpoint Inhibitor Colitis.

Immune checkpoint inhibitors (ICI) are treatments for several cancer types. Pathogenesis of ICI-induced colitis is not yet clearly explained as it can be disguised as another form such as inflammatory bowel disease or IBD. Recent studies revealed that ICI-induced colitis is a unique form of colitis wherein the synergy of regulatory T cells with the gut microbiome is involved.