Therapeutic Drug Monitoring for Biological Therapy in Pediatric Inflammatory Bowel Disease

Inflammatory Bowel Diseases (IBD), which include Crohn's disease (CD), ulcerative colitis (UC), and the unclassified form referred to as indeterminate colitis, are most commonly diagnosed during adolescence and early adulthood. In recent decades, an increasing incidence of IBD has been observed in this age group. A wide range of immunomodulatory agents, from corticosteroids to monoclonal antibodies, are now available for the treatment of IBD. These antibodies, known as biologics, target, for example, tumor necrosis factor-alpha (TNF-α; e.g., infliximab and adalimumab), integrin α4β7 (vedolizumab), or interleukin-12/23 (ustekinumab). While infliximab and adalimumab are approved for pediatric use in CD and UC, vedolizumab is only approved for moderate-to-severe UC from the age of 16, and ustekinumab is not approved for pediatric use at all. Nevertheless, vedolizumab and ustekinumab are fr