Rifaximin 200 mg Plus Oral Rehydration vs Oral Rehydration Alone in Children With Acute Diarrhea

NCT07285785 | Recruiting Phase 4 FDA Drug

• 1 other identifier: RFPK1991
• Study Type: interventional
• Target: 54
• Locations: 1 country
• Sites: 10

Brief Summary

The goal of this clinical trial is to learn how rifaximin 200 mg is processed in the body (pharmacokinetics) in children 6 to 11 years old with acute diarrhea that may be caused by bacteria. It will also learn about the safety and effectiveness of rifaximin when given with oral rehydration therapy (ORT) compared with ORT alone. The main questions it aims to answer are: How does rifaximin 200 mg move through and leave the body in children with acute diarrhea? Is rifaximin safe for children in this age group? Does rifaximin plus ORT help resolve diarrhea faster than ORT alone? Researchers will compare rifaximin plus ORT to ORT alone to see if adding rifaximin improves outcomes. Participants will: Take one rifaximin 200 mg tablet + ORT three times a day for 3 days or receive ORT alone Receive oral rehydration therapy according to the investigator's standard of care Attend up to 4 clinic visits over 5 days and receive 4 follow-up phone calls Provide blood samples on Day 1 and Day 3 for pharmacokinetic testing (rifaximin group only) Provide stool samples to identify bacterial pathogens Keep a diary of stool frequency and consistency to help determine when diarrhea resolves Be monitored for side effects, vital signs, and laboratory changes

Conditions

Diarrhea; Gastroenteritis; Bacterial Infection; Acute Diarrhea

Keywords

pediatric; children; rifaximin; xifaxan; Oral Rehydration Therapy (ORT); acute diarrhea; bacterial diarrhea; gastroenteritis; open-label; randomized; ages 6-11; diarrhea

Outcome Measures

Primary Outcomes (5)

• Peak Plasma Concentration (Cmax) of Rifaximin

  Cmax levels following rifaximin 200 mg + ORT

  Days 1 and 3

• Time to Maximum Plasma Concentration (Tmax) of Rifaximin

  Tmax for rifaximin following rifaximin 200 mg + ORT

  Days 1 and 3

• Area Under the Plasma Concentration-Time Curve From Time 0 to Last Quantifiable Concentration (AUC0-last) for Rifaximin

  Area under the concentration-time curve to last measurable concentration

  Days 1 and 3

• Area Under the Plasma Concentration-Time Curve Over the Dosing Interval (AUC0-τ) for Rifaximin

  Area under the concentration-time curve over the dosing interval

  Days 1 and 3

• Proportion of participants with Clinical Cure

  Proportion of participants achieving clinical cure, defined as either: 1. No unformed stools within a 48-hour period with no fever (with or without other clinical symptoms such as abdominal cramps or pain, excess gas/flatulence, nausea, vomiting, urgency, tenesmus); or 2. No watery stools and no more than two soft stools within a 24-hour period with no fever and no other clinical symptoms except for mild excess gas/flatulence.

  Up to Day 5 (End of Treatment)

Secondary Outcomes (4)

• Time to Last Unformed Stool (TLUS)

  Up to Day 5 (End of Treatment)

• Incidence of Treatment-Emergent Adverse Events (AEs)

  Day 1-30

• Change From Baseline in Clinical Laboratory Parameters

  Day 1-30

• Change From Baseline in Vital Signs

  Day 1-30

Other Outcomes (1)

• Detection of Bacterial Pathogens in stool samples

  Screening (Day -2 to Day 1)

Study Arms (2)

Rifaximin 200 mg + ORT

EXPERIMENTAL

rifaximin 200 mg tablets orally three times daily for 3 days plus oral rehydration therapy (ORT) administered per investigator standard of care

Drug: Rifaximin 200 mg Tablet; Other: Oral Rehydration Therapy (ORT)

ORT Alone

ACTIVE COMPARATOR

ORT administered per investigator standard of care without rifaximin.

Other: Oral Rehydration Therapy (ORT)

Interventions

Oral Rehydration Therapy (ORT) OTHER

Participants receive oral rehydration solution according to the investigator's standard of care. This is administered either alone (for the ORT-alone arm) or in combination with rifaximin (for the rifaximin + ORT arm). Participants or caregivers complete a daily diary documenting stool frequency, stool consistency, and related symptoms.

ORT Alone; Rifaximin 200 mg + ORT

Rifaximin 200 mg Tablet DRUG

Participants receive rifaximin 200 mg tablets orally three times daily (TID) for 3 days in combination with oral rehydration therapy (ORT). Blood samples for pharmacokinetic analysis are collected on Day 1 and Day 3 at pre-dose, 1 hour post-dose, and 6 to 8 hours post-dose.

Rifaximin 200 mg + ORT

Eligibility Criteria

• Age: 6 Years - 12 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17)

You may qualify if:

• Parent/legally authorized representative and participant, as applicable, have provided written informed consent/assent, are able to understand, and agree to comply with, all study procedures and requirements.
• Participant is between 6 to 11 years of age (inclusive)
• Participant weighs at least 15 kg (33 lbs) at Screening
• Participant is able to swallow pills
• Participant has diarrhea of suspected bacterial etiology defined by:
• At least 3 unformed stools in the last 24 hours prior to Screening
• Illness for less than 96 hours at Screening
• Clinical presentation consistent with acute infectious diarrhea of suspected bacterial etiology
• The participant agrees to use a highly effective method of contraception (if applicable) and to have urine pregnancy tests. Applies to females of childbearing potential (defined as postmenarche). Participants must practice at least 1 of the following medically acceptable methods of birth control throughout the study:
• Applicable to:
• All Post-Menarche Female Particpants:
• Highly effective hormonal contraception methods such as oral, implantable, injectable, vaginal ring, or transdermal contraception for a minimum of 1 full cycle (based on the participant's usual menstrual cycle period) before study drug administration.
• Total abstinence from sexual intercourse since the last menses before screening and agrees to total abstinence from screening until at least 30 days after last study drug administration.
• Intrauterine device.
• All Males Participants:

You may not qualify if:

• Participant has a history of chronic diarrhea (defined as loose or watery stools persisting for at last 4 consecutive weeks) within 12 months prior to onset of current acute illness.
• Participant is unable to eat or drink.
• Participant has clinical features suggestive of invasive or severe bacterial diarrhea requiring alternative therapy (e.g., frank blood in stool, mucoid diarrhea with systemic symptoms such as high fever, severe abdominal cramping or tenderness, or signs of sepsis).
• Participant has taken \>2 doses of anti-diarrheal therapies in the 24 hours prior to randomization.
• Participant has taken any oral antimicrobial drug within 14 days of randomization.
• Participant has a clinically significant or unstable medical condition, in the opinion of the Investigator, (including, but not limited to, evidence of severe dehydration noted by tachycardia, abnormal blood pressure, or decreased skin turgor) at the Screening visit.
• Participant has a known hypersensitivity or allergy to Xifaxan®, rifampin, rifamycin-derived antibiotics, or any of the components of the rifaximin (Xifaxan®) formulations used in this study.
• Participant is pregnant or lactating or plans to become pregnant during the study.
• Participant has had a previous history of malignancy.
• Participant has a history of tuberculosis infection and/or has received treatment for tuberculosis infection.
• Participant has any concurrent illness, disability or circumstance that may affect the interpretation of clinical data, could cause noncompliance with treatment or visits or otherwise contraindicates participation in this study in the opinion of the Investigator.
• Participant has had significant blood loss within the 30 days prior to the Screening visit which prevents the collection of the blood volume required for this study.
• Participant has participated in an investigational drug or device study within the 30 days prior to randomization.
• Participant is an immediate household family member of study site personnel directly involved in the conduct of this study.
• Participant is taking a medication that is prohibited per Section 4.5 (Prohibited Therapy).

Sponsors & Collaborators

• Bausch Health Americas, Inc.: lead

Study Sites (10)

Alliance Research Institute

Lynwood, California, 90262, United States

RECRUITING

Direct Helpers

Hialeah, Florida, 33012, United States

RECRUITING

SouthCoast Research Center

Miami, Florida, 33136, United States

RECRUITING

Oceane7 Medical & Research Center, Inc

Miami, Florida, 33144, United States

RECRUITING

Rophe Adult & Pediatric Medicine

Union City, Georgia, 30291, United States

RECRUITING

Innovative Clinical Research Center

Island Lake, Illinois, 60042, United States

RECRUITING

Cyn3rgy Research Corporation

Gresham, Oregon, 97030, United States

RECRUITING

Little Stars Pediatrics / Tattva Trials

Prosper, Texas, 75078, United States

RECRUITING

LinQ Research

Rosharon, Texas, 77583, United States

RECRUITING

Tekton Research

Richmond, Virginia, 23233, United States

RECRUITING

MeSH Terms

Conditions

Diarrhea; Gastroenteritis; Bacterial Infections

Interventions

Rifaximin; Tablets; Fluid Therapy

Condition Hierarchy (Ancestors)

Signs and Symptoms, Digestive; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Gastrointestinal Diseases; Digestive System Diseases; Bacterial Infections and Mycoses; Infections

Intervention Hierarchy (Ancestors)

Rifamycins; Heterocyclic Compounds, 4 or More Rings; Heterocyclic Compounds, Fused-Ring; Heterocyclic Compounds; Lactams, Macrocyclic; Macrocyclic Compounds; Polycyclic Compounds; Dosage Forms; Pharmaceutical Preparations; Drug Therapy; Therapeutics

Central Study Contacts

Angela Moore

CONTACT

843-877-2756; angela.moore@bauschhealth.com

Maryanne Santilli

CONTACT

Study Design

• Study Type: interventional
• Phase: phase 4
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: December 2, 2025
• First Posted: December 16, 2025
• Study Start: February 11, 2026
• Primary Completion (Estimated): April 20, 2027
• Study Completion (Estimated): July 31, 2027
• Last Updated: August 13, 2026

Record last verified: 2026-08

Data Sharing

• IPD Sharing: Will not share

Locations

US (10)