Zelnorm Clinical Trials and Studies
Zelnorm Information
Zelnorm Clinical Trials and Studies
In three multicenter, double-blind, placebo-controlled Zelnorm studies, 2,470 women (mean age 43 years [range 17-89 years]; 86% Caucasian, 10% African American) with at least a 3-month history of IBS symptoms prior to the study baseline period that included abdominal pain, bloating and constipation received either Zelnorm (tegaserod maleate) 6 mg b.i.d. or placebo. In all patients, constipation was characterized by at least two of the following three symptoms each occurring ≤ 25% of the time over a 3-month period: < 3 bowel movements/week, hard or lumpy stools, or straining with a bowel movement. Study design consisted of a 4-week placebo-free baseline period followed by a 12-week double-blind Zelnorm treatment period. Study 1 and 2 evaluated a fixed dose regimen of tegaserod 6 mg b.i.d. while Study 3 utilized a dose-titration design.
Each week of the 4-week placebo-free baseline period and the 12-week double-blind treatment period, patients were asked the question, "Please consider how you felt this past week in regard to your IBS, in particular your overall well-being, and symptoms of abdominal discomfort, pain and altered bowel habit. Compared to the way you usually felt before entering the study, how would you rate your relief of symptoms during the past week?" The response variable consisted of the following 5 categories: completely relieved, considerably relieved, somewhat relieved, unchanged, or worse. Patients were classified as responders within a month if they were considerably or completely relieved for at least two of the four weeks, or if they were at least somewhat relieved for each of the four weeks.
The differences in Zelnorm response rates vs. placebo were greater at month 1 than month 3.
The same efficacy variable (i.e., complete relief, considerable relief, somewhat relief, unchanged, worse) was analyzed on a weekly basis. The proportion of patients with complete, considerable or somewhat relief at weeks 1, 4, 6, 8 and 12.
In addition, individual symptoms of abdominal pain/discomfort and bloating were assessed daily using a 6 or 7 point intensity scale. A positive response was defined as at least a 1 point reduction in the scale. During the first four weeks in the fixed dose studies, 8 to 11% more Zelnorm-treated patients than placebo patients were responders for abdominal pain/discomfort. Similarly, 9 to 12% more Zelnorm-treated patients were responders for bloating. Corresponding differences at month 3 were 1 to 10% for abdominal pain/discomfort and 4 to 11% for bloating. Patients on Zelnorm also experienced an increase in median number of stools from 3.8/week at baseline to 6.3/week at month 1 and 6.0/week at month 3, while placebo patients increased from 4.0/week to 5.1/week at month 1 and 5.5/week at month 3.
The efficacy of Zelnorm beyond 12 weeks has not been studied.
