A double-blind comparison of oral versus rectal mesalamine versus combination therapy in the treatment of distal ulcerative colitis

Abstract

Objectives: The aim of this study was to compare the efficacy of mesalamine rectal suspension enema (Rowasa) alone, oral mesalamine tablets (Asacol) alone, and the combination of mesalamine enema and mesalamine tablets in patients with active mild-to-moderate distal ulcerative colitis.

Methods: Sixty outpatients with ulcerative colitis at least 5 cm above the anal verge and not more than 50 cm, inclusive, and a total disease activity index (DAI) score between 4 and 10, inclusive, were randomized to either mesalamine rectal enema (n = 18) once nightly, oral mesalamine 2.4 g/day (n = 22), or a combination of both treatments (n = 20). Placebo capsules and enemas were used to maintain a blind procedure. Total DAI scores and abbreviated DAI scores were evaluated at wk 3 and 6, and wk 1 and 2, respectively. Patients recorded the amount of blood in stools, urgency, straining at stools, and abdominal pain in daily diaries. Physicians and patients rated overall improvement at each visit.

Results: At wk 6, combination therapy produced a greater improvement (-5.2) in total DAI scores than did either mesalamine enema (-4.4) or mesalamine tablet (-3.9) therapy alone; similar treatment differences were observed at wk 3. Compared with patients given mesalamine enemas or mesalamine tablets, combination-therapy patients reported an absence of blood in stools significantly sooner and, at all visits, the combination therapy group had the highest percentage of patients who reported no blood in their stools. Physicians' and patients' ratings of improvement indicated that combination therapy significantly improved disease status, compared with mesalamine tablet therapy alone. All treatments were well tolerated.

Conclusions: The combination of oral and rectal mesalamine therapy was well tolerated and produced earlier and more complete relief of rectal bleeding than oral or rectal therapy alone.