Rifaximin Therapy vs Low FODMAP Diet In IBS

Rifaximin Therapy Versus Low FODMAP Diet In Irritable Bowel Syndrome: A Randomised Controlled Trial

Functional gastrointestinal disorders (FGIDs) are common and from the most recent global epidemiology study, an estimated 40% of the world population suffer from the condition. FGIDs cause significant morbidity to patients, despite not influencing mortality. IBS is among the most important functional gastrointestinal disorder with an estimated 3.8 to 9.2 % of the general population worldwide were affected by this disorder.

Rifaximin (gut specific antibiotic) and low FODMAP diet (dietary based therapy) were proven to be effective in treating irritable bowel syndrome (IBS), however there was no head-to-head study comparing both treatments. This study will help doctors to understand the efficacy of different IBS/SIBO treatments. With the evaluation of factors that can predict treatment response, doctor could potentially treat IBS and SIBO more effectively in future.

The purpose of the study is to compare the clinical symptoms and psychological improvement in patients with irritable bowel syndrome (IBS) after treatment with Rifaximin versus treatment with low FODMAP diet. The factors that is associated with treatment response will also be evaluated. In IBS patients with small intestinal bacterial overgrowth (SIBO), eradication rate of SIBO will be evaluated.

Study Overview

• Status: Recruiting
• Conditions: Irritable Bowel Syndrome; Small Intestinal Bacterial Overgrowth
• Intervention / Treatment: Drug: Rifaximin; Other: Low FODMAP diet

• Study Type: Interventional
• Enrollment (Anticipated): 100
• Phase: Phase 4

Contacts and Locations

• Study Contact: Name: Kee-Huat Chuah, MBBS; Phone Number: +60379492965; Email: chuah319@yahoo.com

Study Locations

• Malaysia
  • Kuala Lumpur, Malaysia
    • Recruiting
    • University Malaya Medical Centre
    • Contact: Kee Huat Chuah, MBBS

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 80 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Patients diagnosed with Irritable bowel syndrome using Rome III diagnostic criteria with Abdominal Pain/ Discomfort Intensity of weekly average of worst abdominal pain/ discomfort in past 24 hours score of ≥ 3.0 on a 0 to 10 point scale AND Stool Consistency of at least 2 days per week with at least one stool that has a consistency of Type 6 or Type 7 BSS or <3 CSBM per week
2. Subject who can provide written informed consent and willingness to comply with the requirement of the protocol
3. Able to communicate in English, Malay, or Mandarin languages

Exclusion Criteria:

1. Patients with known hypersensitivity or contraindication to Rifaximin
2. Pregnant / breastfeeding women
3. Patients who are on probiotics for the past 1 month
4. Presence of family history of GI malignancy or alarm features suggested malignancy - e.g. Unintentional weight loss (≥ 10% of body weight in recent 6 months), GI bleeding
5. History of gastrointestinal (GI) malignancy
6. Patients with any hepatobiliary or pancreatic diseases
7. Patients with severe depression, anxiety, or other psychological disorder
8. Patients with any terminal disease
9. Other conditions determined by the investigator to be inappropriate for this clinical study

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Antibiotics	Drug: Rifaximin; Administration route: PO Rifaximin 400mg TDS for 2 weeks
Active Comparator: Dietary based therapy	Other: Low FODMAP diet; Low FODMAP diet under dietitian guidance for 4 weeks

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Proportion of subjects with adequate relief of composite of abdominal symptom (pain/discomfort) and stool symptom (frequency/ consistency) after treatment.	Adequate relief was defined as self-reported relief of both symptoms (abdominal symptom and stool symptom) at least in week 2 or 4. (Subjects will be provided with self-reported questionnaires for week 2 and 4). For IBS-D, relief was defined as a decrease of at least 30% from baseline in weekly mean ratings of IBS-related abdominal pain or discomfort and a weekly decrease of at least 50% in the number of days per week with at least one stool that has a consistency of Type 6 or 7 compared with baseline. For IBS-C, relief was defined as a decrease of at least 30% from baseline in weekly mean ratings of IBS-related abdominal pain or discomfort and an increase of 1 or more complete spontaneous bowel movement (CSBM) per week compared with baseline. For IBS-M, relief was defined as fulfilled both IBS-D and IBS-C symptom relief criteria.	4 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Proportion of patients who had relief was determined from the patients' weekly assessments of global IBS symptoms, bloating, abdominal pain/ discomfort, and stool consistency/ frequency after treatment with Rifaximin or low FODMAP diet	Rated on a 5-point scale: 2 = Significantly Relieved, 1 = Moderately Relieved, 0 = Unchanged, -1 = Moderately Worse, and -2 = Significantly Worse for at least 50% of the days in a week. Relief was defined as a score of either 2 (Significantly Relieved) or 1 (Moderately Relieved).	4 weeks
Symptom severity score improvement	The symptom severity was assessed by the IBS-symptom severity (IBS-SS) score from baseline to 4 weeks after initiation of treatment. Total scores ranging from 0 to 500	4 weeks
Proportion of patients with SIBO who had eradication of SIBO after treatment	as measured by glucose hydrogen breath test	6 weeks
Assessment of factors that were associated with treatment response	Baseline characteristic (age, gender, ethnicity), IBS subtype (IBS-D, IBS-C IBS-mixed), and SIBO status (positive or negative) of patients who responded to treatment (based on primary outcome) will be compared to non-responder	6 weeks
Change in Health-Related Quality of Life (HRQOL) score	HRQOL will be assessed using EuroQol-5D (EQ-5D) instrument. Overall utility score (as mean value) was calculated with a range score from 0 (worst health scenario) to a maximum of 1.0 (best health scenario).	4 weeks

Collaborators and Investigators

• Sponsor: University of Malaya
• Investigators: Principal Investigator: Kee-Huat Chuah, MBBS, University Malaya

Study record dates

Study Major Dates

• Study Start (Actual): April 22, 2021
• Primary Completion (Anticipated): May 31, 2024
• Study Completion (Anticipated): May 31, 2024

Study Registration Dates

• First Submitted: January 21, 2021
• First Submitted That Met QC Criteria: April 9, 2021
• First Posted (Actual): April 12, 2021

Study Record Updates

• Last Update Posted (Actual): May 16, 2023
• Last Update Submitted That Met QC Criteria: May 14, 2023
• Last Verified: May 1, 2023

More Information

Terms related to this study

• Keywords: IBS; Rifaximin; low FODMAP diet; SIBO
• Additional Relevant MeSH Terms: Digestive System Diseases; Pathologic Processes; Disease; Gastrointestinal Diseases; Colonic Diseases, Functional; Colonic Diseases; Intestinal Diseases; Syndrome; Irritable Bowel Syndrome; Anti-Infective Agents; Gastrointestinal Agents; Anti-Bacterial Agents; Rifaximin
• Other Study ID Numbers: 2021001

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No