title: Systematic review: does concurrent therapy with 5-ASA and immunomodulators in inflammatory bowel disease improve outcomes?
abstract: BACKGROUND
  With greater use of immunomodulators in inflammatory bowel disease (IBD), it is uncertain whether concurrent therapy with both 5-aminosalicylic acid [5-ASA, mesalazine (mesalamine)] and an immunomodulator is necessary.
  
  
  OBJECTIVE
  To determine whether concurrent therapy with both 5-ASA and immunomodulator(s) improves outcomes in IBD.
  
  
  METHODS
  Systematic review with search terms 'azathioprine, 6-mercaptopurine, thiopurine(s), 5 aminosalicylic acid, mesalazine, inflammatory bowel disease, ulcerative colitis, Crohn's disease, immunosuppressant(s), immunomodulator and methotrexate' in November 2007 to identify clinical trials on concurrent 5-ASA and immunomodulator therapy.
  
  
  RESULTS
  Two small controlled studies were found. Neither showed a benefit on disease control beyond immunomodulator monotherapy. Potential pharmacological interactions exist between 5-ASA and thiopurines. Whilst circumstantial, epidemiological and laboratory evidence suggests that 5-ASA may assist colorectal cancer (CRC) chemoprevention, it may simply be via anti-inflammatory effects. With changes in practice, ethical issues and the long lead-time needed to demonstrate or disprove an effect, no clinical studies can/will directly answer this. The costs of avoiding one CRC in IBD may be as low as 153 times the annual cost of 5-ASA therapy.
  
  
  CONCLUSIONS
  It is unclear whether concurrent 5-ASA and immunomodulator therapy improves outcomes of disease control, drug toxicity or compliance. Concurrent therapy of 5-ASA and immunomodulators may decrease CRC risk at 'acceptable' cost.
authors.affiliation: Departments of Gastroenterology and Hepatology, Royal Adelaide Hospital and School of Medicine, University of Adelaide, Adelaide, SA, Australia. jane.andrews@health.sa.gov.au
authors.forename: J M
authors.initials: JM
authors.lastname: Andrews
authors.forename: S P L
authors.initials: SP
authors.lastname: Travis
authors.forename: P R
authors.initials: PR
authors.lastname: Gibson
authors.forename: C
authors.initials: C
authors.lastname: Gasche
mesh_terms: D000636:Aminosalicylic Acids / Q000627:therapeutic use*; D004359:Drug Therapy, Combination; D006801:Humans; D007155:Immunologic Factors / Q000627:therapeutic use*; D015212:Inflammatory Bowel Diseases / Q000188:drug therapy*; D019804:Mesalamine / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D000636:Aminosalicylic Acids; D007155:Immunologic Factors; D019804:Mesalamine