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: 5

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

Keywords

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

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 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:

• Consent and assent are appropriately obtained prior to any study related activities, including discontinuation of any prohibited medications (subjects must sign an assent for the study and a parent or a legal guardian must sign the informed consent).
• Subject is between 6 to 11 (and 11 months) years of age, inclusive, and weighs at least 15 kg (33 lbs) at Screening.
• Females of childbearing (reproductive) potential must have a negative urine and serum pregnancy test at Screening and agree to use a highly effective method of contraception throughout their participation in the study. Acceptable methods of contraception are those alone or in combination, that result in a low failure rate (ie, less than 1% per year) when used consistently and correctly and include hormonal methods (oral, injected or implanted), intrauterine device or intrauterine system or double barrier methods (simultaneous use of a physical barrier method by the subject and male partner, including a male condom and an occlusive cap \[diaphragm or cervical/vault cap\] with spermicidal). Abstinence or partner(s) with a vasectomy may be considered an acceptable method of contraception at the discretion of the Investigator.
• NOTE: Female subjects are considered of child-bearing potential if they are (a) physiologically capable of becoming pregnant, defined as a female who has experienced menarche and (b) they will be, or could possibly be, engaging in sexual activity during the course of the study.
• Subject has diarrhea of suspected bacterial etiology defined by:
• At least 3 unformed stools in the last 24 hours prior to Screening.
• A fever ≥ 100.4°F (38°C) and ≤ 102.2°F (39°C) or has had a fever of ≥ 100.4°F (38°C) and ≤ 102.2°F (39°C) at any time since the development of abdominal pain or diarrhea.
• Illness for less than 96 hours at Screening.
• Parent or legal guardian and subject, when applicable based on aged, are capable of understanding the requirements of the study and willing to comply with all study procedures and visits.

You may not qualify if:

• Subject has a history of chronic diarrhea.
• Subject is unable to eat or drink.
• Subject has at least one of the following signs or symptoms:
• Presence of fever \>39°C (\>102.2°F).
• Presence of frank blood in stool.
• Subject has taken \>2 doses of anti-diarrheal therapies in the 24 hours prior to randomization.
• Subject has taken any oral antimicrobial drug within 14 days of randomization.
• Subject has an 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.
• Subject has known, clinically significant hepatic disease manifested by twice the age and sex-adjusted upper limit of normal (2 × ULN) for any of the following liver function tests: alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl transferase, alkaline phosphatase, or total bilirubin (except in isolated elevation of unconjugated bilirubin).
• Subject has known, clinically significant renal disease (eg, 1.5 × ULN of serum creatinine or 2 × ULN of blood urea nitrogen levels).
• Subject has serum sodium of ≥150 mEq/L and serum potassium ≤3.0 mEq/L.
• Subject 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.
• Subject is pregnant or lactating or plans to become pregnant during the study.
• Subject has had a previous history of malignancy.
• Subject has a history of tuberculosis infection and/or has received treatment for tuberculosis infection.

Sponsors & Collaborators

• Bausch Health Americas, Inc.: lead

Study Sites (5)

Direct Helpers

Hialeah, Florida, 33012, United States

NOT YET RECRUITING

SouthCoast Research Center

Miami, Florida, 33136, United States

RECRUITING

Oceane7 Medical & Research Center, Inc

Miami, Florida, 33144, 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

John Lahey VP, Clinical Operations

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: March 18, 2026

Record last verified: 2026-03

Data Sharing

• IPD Sharing: Will not share

Locations

US (5)