Yongjun Wang, John K MacDonald, Ben Vandermeer, Anne Marie Griffiths, Wael El‐Matary

Methotrexate, a folate antagonist, is an immunosuppressant drug that is effective for treating several inflammatory disorders including Crohn's disease. Ulcerative colitis, a related chronic inflammatory bowel disease, can be challenging to treat. T his updated systematic review summarizes the current evidence on the use of methotrexate for induction maintenance of remission in ulcerative colitis. The objectives of this review were to assess the efficacy and safety of methotrexate for maintenance of remission in patients with ulcerative colitis. We searched MEDLINE, EMBASE, CENTRAL and the Cochrane IBD/FBD group specialized trials register from inception to June 26, 2014. Study references and review papers were also searched for additional trials. Abstracts from major gastroenterological meetings were searched to identify research published in abstract form only. Randomized controlled trials in which methotrexate was compared to placebo or an active comparator in patients with quiescent ulcerative were considered for inclusion. Two authors independently extracted data and assessed the risk of bias for each study. The primary outcome was the occurrence of clinical or endoscopic relapse as defined by the primary studies. Secondary outcomes included frequency and nature of adverse events, change of disease activity score and steroid-sparing effect. We calculated the risk ratio and corresponding 95% confidence interval for dichotomous outcomes. Data were analyzed on an intention-to-treat basis. The overall quality of the evidence supporting the outcomes was evaluated using the GRADE criteria. Three trials (165 patients) fulfilled the inclusion criteria. One study compared oral methotrexate (12.5 mg/week) to placebo, another compared oral methotrexate (15 mg/week) to 6-mercaptopurine (6-MP, 1.5 mg/kg/day) or 5-aminosalicylic acid (5-ASA, 3 g/day) and the other compared methotrexate (15 mg/week) in combination sulfasalazine (3 g/day) to sulfasalazine. The placebo-controlled study was rated as low risk of bias. The study comparing methotrexate to 6-MP and 5-ASA was rated as high risk of bias and the study assessing methotrexate and sulfasalazine was rated as unclear risk of bias for sequence generation, allocation concealment and blinding. The placebo-controlled study found no statistically significant differences in the proportion of patients who maintained remission. At nine months, 36% (5/14) of methotrexate patients maintained remission compared to 54% (10/18) of placebo patients (RR 0.64, 95% CI 0.28 to 1.45). A GRADE analysis indicated that the overall quality of the evidence for this outcome was low due to very sparse data (15 events). The study comparing combination therapy to sulfasalazine found no statistically significant difference in the proportion of patients who maintained remission. At 12 months, 100% (14/14) of patients in the combination group maintained remission compared to 75% (9/12) of sulfasalazine patients (RR 1.32, 95% CI 0.94 to 0.86), A GRADE analysis indicated that the overall quality of the evidence for this outcome was very low due to unknown risk of bias and very sparse data (23 events). There were no statistically significant differences in maintenance of remission rates between methotrexate and 6-MP or between methotrexate and 5-ASA. At 76 weeks, 14% (1/7) of methotrexate patients maintained remission compared to 64% (7/11) of 6-MP patients (RR 0.22, 95% CI 0.03 to 1.45) and 0% (0/2) of 5-ASA patients (RR 1.13, 95% CI 0.06 to 20.71). A GRADE analysis indicated that the overall quality of the evidence from this study was very low due to high risk of bias and very sparse data. Adverse events reported in these studies included transient leucopenia, migraine, nausea and dyspepsia, mild alopecia, mild increase in aspartate aminotransferase levels, peritoneal abscess, hypoalbuminemia, severe rash and atypical pneumonia AUTHORS' CONCLUSIONS: The results for efficacy and safety outcomes between methotrexate and placebo, methotrexate and sulfasalazine, methotrexate and 6-mercaptopurine and methotrexate and 5-aminosalicylic acid were uncertain. Whether a higher dose or parenteral administration of methotrexate would be effective in quiescent ulcerative colitis is unknown. At present there is no evidence supporting the use of methotrexate for maintenance of remission in ulcerative colitis. More studies are needed to determine the efficacy and safety of methotrexate maintenance therapy in patients with quiescent ulcerative colitis. Large scale methodologically rigorous randomized controlled trials are needed. These studies should investigate higher doses of methotrexate (e.g. 15 to 25 mg/week) and parenteral administration.