title: Biologic concentration testing in inflammatory bowel disease.
abstract: Anti-TNF medications have revolutionized the care of patients with inflammatory bowel disease. However, despite an initial robust effect, loss of response is common and long-term results are disappointing. Much of this lack of durability may be due to inadequate dose optimization, and recent studies suggest a correlation between serum drug concentrations and clinical outcomes. Currently, in clinical practice, measurement of drug concentrations and antibodies to drug are typically performed only when a patient presents with active inflammatory bowel disease symptoms or during a potential immune-mediated reaction to anti-TNF ("reactive" setting). However, proactive monitoring of anti-TNF concentrations with titration to a therapeutic window (i.e., therapeutic concentration monitoring) represents a new strategy with many potential clinical benefits including prevention of immunogenicity, less need for IFX rescue therapy, and greater durability of IFX treatment. This review will cover the salient features of anti-TNF pharmacokinetics and pharmacodynamics and provide a rational approach for the use of anti-TNF concentration testing in both the reactive and proactive settings.
authors.affiliation: *Center for Inflammatory Bowel Diseases, Division of Gastroenterology, Beth-Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts; †Division of Gastroenterology, Hepatology and Nutrition, University of Minnesota, Minneapolis, Minnesota; and ‡Division of Gastroenterology, University of California San Diego, San Diego, California.
authors.forename: Byron P
authors.initials: BP
authors.lastname: Vaughn
authors.forename: William J
authors.initials: WJ
authors.lastname: Sandborn
authors.forename: Adam S
authors.initials: AS
authors.lastname: Cheifetz
mesh_terms: D000911:Antibodies, Monoclonal / Q000097:blood*; D016903:Drug Monitoring; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000097:blood* / Q000188:drug therapy; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors* / Q000276:immunology
chemical_list: D000911:Antibodies, Monoclonal; D014409:Tumor Necrosis Factor-alpha