Evaluating the Effect Of Rifaximin on the Gut Microbiota and Metabolome in SIBO Using CapScan®

Evaluating the Effect of Rifaximin on the Regional Composition of the Gut Microbiota and Metabolic Profiles of Subjects With SIBO Using the CapScan® Collection Capsule

We will sample intestinal microbiota using a microbiome sampling capsule in patients with Small Intestinal Bacterial Overgrowth (SIBO)

Study Overview

• Status: Recruiting
• Conditions: Small Intestinal Bacterial Overgrowth
• Intervention / Treatment: Device: CapScan collection capsule

Detailed Description

Prospective, open-label, single-arm, non-randomized, multi-center study designed to evaluate the effect of the antibiotic rifaximin on the regional composition of the gut microbiota and metabolic profiles of subjects diagnosed with SIBO, using the CapScan collection capsule.

• Study Type: Interventional
• Enrollment (Estimated): 34
• Phase: Phase 1

Contacts and Locations

• Study Contact: Name: Jennifer Taufui; Phone Number: (650) 988-7530; Email: svgistaff@gmail.com

Study Locations

• United States
  • California
    • Mountain View, California, United States, 94040
      • Recruiting
      • Silicon Valley Gastroenterology
      • Contact: Jennifer Taufui; Email: svgistaff@gmail.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Study Population

SIBO patients

Description

Inclusion Criteria:

• Males or females 18 years of age or older and 80 years of age or younger at the time of the first Screening Visit.
• ASA Classification 1 or 2.
• For women of childbearing potential, negative urine pregnancy test within 7 days of Screening Visit.
• Willingness to use highly effective contraception during the entire study period (e.g.: implants, injectables, oral contraceptives, intra-uterine device or declared abstinence).
• Subject is fluent in English and understands the study protocol and informed consent and is willing and able to comply with study requirements and sign the informed consent form.
• Positive for at least one clinical symptom consistent with SIBO.
• Positive lactulose breath test for SIBO, by Hydrogen (H2) criteria.
• Prescribed, but has not started, a two-week course of Rifaximin for SIBO.

Exclusion Criteria:

• History of any of the following: Prior gastric or esophageal surgery, including lap banding or bariatric surgery, bowel obstruction, gastric outlet obstruction, diverticulitis, inflammatory bowel disease, ileostomy or colostomy, gastric or esophageal cancer, achalasia, esophageal diverticulum, active dysphagia or odynophagia.
• Actively taking a proton-pump-inhibitor medication within 30 days of enrollment
• Pregnancy or planned pregnancy within 30 days from Screening Visit, or breast-feeding
• Any form of active substance abuse or dependence (including drug or alcohol abuse), unstable medical or psychiatric disorder, or any chronic condition susceptible, in the opinion of the investigator, to interfere with the conduct of the study
• A clinical condition that, in the judgment of the investigator, could potentially pose a health risk to the subject while involved in the study

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Sampling of gut microbiota	> 75% of the retrieved CapScan devices to provide at least 3 million metagenomic DNA sequencing reads of gut microbes from the intestinal tract, and at least 900 annotated gut metabolites.	56 days
Sampling of gut metabolome	>75% of the retrieved CapScan devices to provide at least 900 annotated gut metabolites.	56 days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Effect of rifaximin on gut microbiota	Determine the effect of rifaximin on the regional compositions of the gut microbiota among SIBO patients by assessing the diversity, centroids and distributions of microbial taxa from sequenced CapScan samples of each subject before and after rifaximin at 5 time points.	56 days
Effect of rifaximin on gut metabolome	Determine the effect of rifaximin on the regional compositions of the gut metabolites among SIBO patients by assessing the changes to metabolite classes and metabolic pathways as measured by LC/MS-MS analysis of CapScan samples for each subject before and after rifaximin at 5 time points.	56 days

Collaborators and Investigators

• Sponsor: Envivo Bio Inc
• Investigators: Principal Investigator: George Triadafilopoulos, Silicon Valley Gastroenterology

Study record dates

Study Major Dates

• Study Start (Actual): February 15, 2024
• Primary Completion (Estimated): February 28, 2026
• Study Completion (Estimated): February 28, 2026

Study Registration Dates

• First Submitted: February 28, 2024
• First Submitted That Met QC Criteria: March 5, 2024
• First Posted (Actual): March 7, 2024

Study Record Updates

• Last Update Posted (Actual): June 11, 2025
• Last Update Submitted That Met QC Criteria: June 8, 2025
• Last Verified: June 1, 2025

More Information

Terms related to this study

• Other Study ID Numbers: EB04

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