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Study to Assess the Efficacy and Safety of Rifaximin Administered BID in the Treatment of Patients With Diarrhea-Associated Irritable Bowel Syndrome

Phase 2
Completed
Conditions
Irritable Bowel Syndrome
Registration Number
NCT00269412
Lead Sponsor
Bausch Health Americas, Inc.
Brief Summary

This is placebo-controlled study of three rifaximin doses in patients with DIBS. Subjects will be randomized to receive daily doses of placebo BID, rifaximin 275 mg BID, rifaximin 550 mg BID, or 1100 mg BID for 14 days. These four groups will subsequently receive an additional two weeks of placebo for a total of 4 weeks of treatment. A fifth group of subjects will receive rifaximin 550 mg BID for a period of 28 days. Subjects who successfully respond to treatment at the end of the 28-day Treatment Phase will be followed in a Post-treatment Phase that includes study visits during Weeks 6, 8, 12 and 16. Subjects who relapse during the Post-treatment Phase will be discontinued from the study.

Detailed Description

While IBS is one of the most common chronic medical conditions the etiology of IBS is unknown. Although not a life-threatening illness, IBS is considered to be a serious condition that has a substantial impact on a subject's day-to-day function. IBS is characterized by abdominal pain and altered bowel habits, including diarrhea, constipation, or alternating diarrhea and constipation. Symptoms are typically intermittent but may be continuous.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
525
Inclusion Criteria
  1. Male or female subject 18 years of age or older.
  2. Irritable bowel syndrome confirmed by the Rome II Criteria
  3. Lower endoscopic examination that demonstrates normal colonic anatomy
Exclusion Criteria
  1. Subject has exclusively constipation-predominant IBS (CIBS) that is characterized by < 3 bowel movements/week or hard and lumpy stools.
  2. Subject has alternating IBS, but is currently presenting with constipation associated IBS symptoms.
  3. Subject has had adequate control of their DIBS and their symptom of bloating the week preceding the screening visit or at the time of randomization. Bloating includes the following symptoms: abdominal fullness, bloating, gas, or swelling.
  4. Subjects has a positive stool culture for O & P (ovum and parasite) and/or Clostridium difficile
  5. Subject has failed to record 2 negative weekly global assessments during the past 10 days prior to randomization.

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Primary Outcome Measures
NameTimeMethod
The primary objective of this trial is to evaluate the efficacy of a 14-day course of oral rifaximin at 550 mg BID versus placebo in providing adequate relief from Diarrhea-associated IBS (DIBS) symptoms.
Secondary Outcome Measures
NameTimeMethod
To evaluate the dose-response relationship of placebo administered for 28 days and rifaximin administered at 275 mg BID, 550 mg BID, or 1100 mg BID for 14 days;
to evaluate the efficacy of 550 mg BID for 4 weeks to determine if there are any differences when treatment is extended for an additional 2-week period when compared to a similar dosing regimen for 2 weeks;
to evaluate the durability of response over a 12-week Post-treatment Phase in subjects with DIBS who achieved a response during the acute Treatment Phase of the study.

Trial Locations

Locations (65)

Mayo Clinic Scottsdale

🇺🇸

Scottsdale, Arizona, United States

Premeire Pharmaceutical Research

🇺🇸

Tempe, Arizona, United States

Advanced Clinical Research Institute

🇺🇸

Anaheim, California, United States

Lovelace Scientific Resources

🇺🇸

Irvine, California, United States

West Gastroenterology Medical Group

🇺🇸

Los Angeles, California, United States

Beverly Hills Gastroenterology

🇺🇸

Los Angeles, California, United States

Medical Associates Research Group

🇺🇸

San Diego, California, United States

Gastroenterology Associates of Fairfield County

🇺🇸

Bridgeport, Connecticut, United States

Connecticut Gastroenterology Institute

🇺🇸

Bristol, Connecticut, United States

Litchfield County Gastroenterology Associates, LLC

🇺🇸

Torrington, Connecticut, United States

Scroll for more (55 remaining)
Mayo Clinic Scottsdale
🇺🇸Scottsdale, Arizona, United States

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