Methotrexate effective for maintenance of remission in Crohn's disease

Clinical question: 
How effective is methotrexate for maintenance of remission in Crohn's disease?
Bottom line: 
Methotrexate (15mg/week) injected intramuscularly for 40 weeks is an effective treatment (NNT* 4) for preventing relapse among patients whose disease became inactive while taking higher doses of intramuscular methotrexate (25mg/week). Side effects occurred in a small number of patients. These side effects were usually mild in nature and included nausea and vomiting, cold symptoms, abdominal pain, headache, joint pain and fatigue. Methotrexate (12.5 to 15mg/week) taken orally was not shown to be an effective treatment for inactive Crohn's disease. * NNT = number needed to treat to benefit 1 individual
The 3 studies differed significantly with respect to methodology. Two studies investigated the efficacy of methotrexate compared to placebo. Two studies looked at methotrexate compared to 6-mercaptopurine, and also investigated oral methotrexate compared to 5-ASA. One well-designed trial provided evidence that methotrexate at a dose of 15mg intramuscularly weekly is safe and effective for maintenance of remission in quiescent Crohn's disease. The other 2 studies suggested methotrexate is safe, but failed to show a benefit for lower doses given orally.
Safe and effective long-term treatments that reduce the need for corticosteroids are required for Crohn's disease. Although purine antimetabolites (such as azathioprine and 6-mercaptopurine) are moderately effective for maintenance of remission, patients often relapse despite treatment with these agents. Methotrexate may provide a safe and effective alternative to more expensive maintenance treatment with tumour-necrosis factor-α antagonists (such as infliximab).
Review CD#: 
February, 2010
Authored by: 
Brian R McAvoy