title: Safety issues with biological therapies for inflammatory bowel disease.
abstract: OBJECTIVE
  The purpose of this review is to summarize recent evidence describing specific complications associated with the use of biological therapy derived from controlled trials and from post-marketing surveillance.
  
  
  RESULTS
  Biological therapies, particularly anti-tumour necrosis factor antibodies, are increasingly used in patients with Crohn's disease and ulcerative colitis. Some adverse events, such as serious infections, are a consequence of the immunomodulatory effect of biological agents, while other complications, such as the induction of autoimmune phenomena, neurotoxicity and the development of an immune response to engineered proteins, are class or molecule-specific. Although the immunopathogenesis of these side effects is often a matter of debate, they have been observed not only in inflammatory bowel disease, but also in other immune disorders such as rheumatoid arthritis and psoriasis.
  
  
  CONCLUSIONS
  The benefits of biological agents clearly outweigh the risks. Nevertheless, they are associated with specific toxicity, and this requires the attention of the clinician.
authors.affiliation: Division of Gastroenterology, University of Leuven Hospitals, Leuven, Belgium. gert.vanassche@uz.kuleuven.ac.be
authors.forename: Gert
authors.initials: G
authors.lastname: Van Assche
authors.forename: Séverine
authors.initials: S
authors.lastname: Vermeire
authors.forename: Paul
authors.initials: P
authors.lastname: Rutgeerts
mesh_terms: D000911:Antibodies, Monoclonal / Q000627:therapeutic use*; D001691:Biological Therapy / Q000379:methods*; D006801:Humans; D007155:Immunologic Factors / Q000627:therapeutic use*; D015212:Inflammatory Bowel Diseases / Q000276:immunology / Q000628:therapy*; D016896:Treatment Outcome; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors
chemical_list: D000911:Antibodies, Monoclonal; D007155:Immunologic Factors; D014409:Tumor Necrosis Factor-alpha