Systematic review: does concurrent therapy with 5-ASA and immunomodulators in inflammatory bowel disease improve outcomes?
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.
Andrews
J M
JM
Departments of Gastroenterology and Hepatology, Royal Adelaide Hospital and School of Medicine, University of Adelaide, Adelaide, SA, Australia. jane.andrews@health.sa.gov.au
Travis
S P L
SP
Gibson
P R
PR
Gasche
C
C
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
D000636:Aminosalicylic Acids; D007155:Immunologic Factors; D019804:Mesalamine