Repeat Drug Therapy for Constipation Effective in Patients with Irritable Bowel Syndrome

Repeat Drug Therapy for Constipation Effective in Patients with Irritable Bowel Syndrome

By Jill Stein

COPENHAGEN—Irritable bowel syndrome (IBS) is often associated with constipation, which complicates the treatment of this condition, and repeat treatment is often needed because of the nature of this disease.

Intermittent, repeat treatment with tegaserod (Zelnorm) provides sustained and consistent relief of constipation-predominant IBS (IBS-C), investigators announced at the 13th United European Gastroenterology Week.

The results are from a multicenter study that evaluated the effect of tegaserod, 6 mg twice daily, versus placebo on multiple IBS symptoms, both with initial treatment and retreatment in women with IBS-C diagnosed by Rome II criteria.

Tegaserod is a selective 5-HT⁴ receptor partial agonist.

“While the efficacy of tegaserod on the symptoms of IBS-C during continuous treatment has been established, its effect on individual symptoms during repeat therapy has not been fully examined,” said Peter Bytzer, MD, head, Medical Gastroenterology Department, Glostrup University, Glostrup, Denmark. “This is important because repeat treatment is often necessary in IBS-C due to the cyclical nature of the disorder.”

The study included a 2-week baseline period, followed by two 4-week treatment periods, separated by a treatment-free interval.

At the end of initial treatment with tegaserod, patients with at least a partial response entered the treatment-free interval period. A partial response was defined as satisfactory relief of overall IBS symptoms and/or abdominal discomfort/pain for at least 2 out of 4 weeks.

Patients entered the second treatment period only if their symptoms recurred. A recurrence was defined as ≤7 days of satisfactory relief of overall IBS symptoms and abdominal discomfort/pain during 4 consecutive weeks.

Patients documented their symptoms of abdominal discomfort/pain and bloating daily, and of constipation weekly, using a questionnaire included in electronic patient diaries.

Overall, 2660 patients were randomized to the first treatment period; 983 were randomized to repeat treatment.

Tegaserod was superior to placebo for all efficacy measures at the end of each treatment period (Table). It was also associated with rapid improvement (as early as day 1) in IBS symptoms during both initial and repeat treatment.

“Overall, our data show that intermittent, repeat treatment with tegaserod provides effective therapy for the chronic and intermittent nature of IBS-C in patients who have initially responded to a first course of such treatment,” Dr Bytzer said.

Table. Improvement in IBS-C symptoms with tegaserod vs placebo

Initial treatment Retreatment

Variable Tegaserod Placebo Tegaserod Placebo

Abdominal discomfort/pain 52.5% 42.8% 54.2% 41.8%

Bloating 50.6% 40.1% 54.4% 41.2%

Constipation* 39.4% 24.8% 45.1% 27.5%

*Improvement in constipation was defined as satisfactory relief in 3 out of 4 weeks.

IBS-C = Constipation-predominant irritable bowel syndrome.