Objectives: To compare the efficacy and safety of mesalamine (5-ASA) suspension enema versus oral sulfasalazine (SAS) in patients with active mild to moderate distal ulcerative colitis.
Methods: Thirty-seven patients were randomly assigned to treatment with either rectal mesalamine, 4 g at night, (n = 19) or oral sulfasalazine, 1 g four times a day, (n = 18) in a 6-wk, double-blind, double-dummy, parallel-group, multicenter study. Patients known to be refractory to SAS or 5-ASA preparations were excluded. Efficacy was assessed by a physician-rated Disease Activity Index (DAI), which included symptom evaluations and sigmoidoscopic findings, by physician-rated Clinical Global Improvement (CGI) scores, and by Patient Global Improvement (PGI) scores. Safety was assessed by adverse event reports, clinical laboratory tests, and physical examination. Results. Mean DAI scores indicated significant improvement from baseline in both treatment groups. CGI scores indicated that 94% of the 5-ASA patients were either "Very Much Improved" or "Much Improved" at wk 6 versus 77% of the SAS patients. PGI ratings showed more improvement in the 5-ASA treatment group than in the SAS group at wk 2 (p = 0.02) and at wk 4 (p = 0.04). Adverse events, primarily headache and nausea, occurred significantly more frequently (p = 0.02) in the SAS than in the 5-ASA group (83 vs 42%). Three patients were withdrawn from SAS treatment because of adverse events.
Conclusions: Rectally administered 5-ASA is as effective as oral SAS in treatment of active distal ulcerative colitis but is associated with fewer and milder adverse events. Patients treated with 5-ASA reported improvement earlier than those treated with SAS.