This report is part of a series of reviews CADTH is conducting on the effectiveness of treatment strategies for patients with inflammatory bowel disease (both Crohn’s disease and ulcerative colitis). The purpose of the current report is to evaluate the clinical and cost-effectiveness of biologics (i.e., adalimumab, infliximab, and vedolizumab) compared with immunomodulators or antibiotics for the management of fistulizing Crohn’s disease.