Inflammatory bowel disease (IBD) coexists in up to 80% of patients with primary sclerosing cholangitis (PSC). PSC-IBD tends to be mild and responsive to mesalamine in most patients. However, some may require immunosuppressive (IMM) or biologic therapy to treat PSC-IBD. The aims of this study are to investigate the rates, predictors, and outcomes of biologic/IMM treatment of PSC-IBD.