Study on the Efficacy and Safety of Fecal Microbiota Transplantation (FMT) in the Treatment of Functional Gastrointestinal Disorders

November 2, 2026 updated by: Zhongshan Hospital Xiamen University

This study is designed to explore the efficacy and safety of fecal microbiota transplantation (FMT) with different delivery routes for patients with functional gastrointestinal disorders (FGIDs). The response to FMT varies greatly, which is related to donor selection, administration route, individual patient characteristics and microbiota compatibility. This single-center, prospective randomized controlled trial plans to enroll 200 FGID patients refractory to conventional medications from OCT 2026 to OCT 2029. Eligible participants will be randomized into a conventional medication group or an FMT group; the FMT group will be further randomized into three subgroups according to transplantation routes: oral capsule, nasojejunal tube and colonoscopic administration. Clinical data, laboratory, imaging and endoscopic results will be collected. Gut microbiota and metabolites will be analyzed before and after treatment. Clinical efficacy and safety will be evaluated at week 12.

Study Overview

Status

Not yet recruiting

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Estimated)

200

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 65 years (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • 1: Aged 1865 years, regardless of gender;

    2: Meeting the Rome IV diagnostic criteria (independently confirmed by two physicians with associate-senior title or above), including subtypes of irritable bowel syndrome: IBS-D (diarrhea-predominant), IBS-C (constipation-predominant), and IBS-M (mixed-type).

    3: Patients with functional constipation (excluding defecatory disorder-related constipation), functional diarrhea, or functional bloating, who have poor response to or intolerance of at least one conventional pharmacotherapy (e.g., antispasmodics, antidiarrheals, osmotic laxatives), with a disease duration of ≥6 months.

    4: Voluntarily participating in this study, signing a written informed consent form, and committing to comply with the study protocol.

Exclusion Criteria:

  • 1: History of prior colectomy or planned surgery within 6 months

    2: contraindications to colonoscopy (severe luminal stenosis, toxic megacolon, risk of perforation, etc.)

    3: comorbid diagnoses: uncontrolled infectious enteritis, positive Clostridioides difficile test, intestinal ischemia, radiation colitis, active diverticular disease

    4: ast or present history of active tuberculosis, active hepatitis B / hepatitis C / HIV infection opportunistic infections

    5: severe systemic diseases: decompensated liver cirrhosis, NYHA Class Ⅲ-Ⅳ heart failure, renal insufficiency (eGFR<30 ml/min)

    6: concomitant malignant tumor or lymphoma

    7: severe immunodeficiency or long-term use of immunosuppressants or systemic glucocorticoids.

    8: Pregnancy, lactation, or planned pregnancy within 6 months

    9: allergy to FMT or study-related medications (laxatives, PPIs, etc.);

    10: poor compliance, psychiatric disorders,or any other conditions deemed by investigators to render the subject unsuitable for participation in the study.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Oral capsule FMT group

Fecal microbiota transplantation via oral capsule combined with conventional symptomatic treatment for functional gastrointestinal disorders.
Biological: Fecal microbiota transplantation (oral capsule)

FMT prepared from screened donor stool, administered by oral capsules, combined with conventional symptomatic treatment.
Experimental: Nasojejunal tube FMT group

Fecal microbiota transplantation delivered through nasojejunal tube combined with conventional symptomatic treatment for functional gastrointestinal disorders.
Biological: Fecal microbiota transplantation (nasojejunal tube)

FMT prepared from screened donor stool, infused via nasojejunal tube, combined with conventional symptomatic treatment.
Experimental: Colonoscopic FMT group

Fecal microbiota transplantation administered by colonoscopic catheter combined with conventional symptomatic treatment for functional gastrointestinal disorders.
Biological: Fecal microbiota transplantation (colonoscopic catheter)

FMT prepared from screened donor stool, delivered through colonoscopic catheter, combined with conventional symptomatic treatment.
Active Comparator: Conventional medication group

Routine symptomatic drug treatment for functional gastrointestinal disorders without fecal microbiota transplantation.
Drug: Conventional symptomatic medications

Routine symptomatic drugs for functional gastrointestinal disorders, without fecal microbiota transplantation.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Clinical response rate at week 12
Time Frame: 12 weeks after enrollment

The proportion of participants achieving clinical response (≥50% reduction in symptom score). Compare treatment responses across FGID subtypes (IBS-C, IBS-D, mixed IBS, functional constipation, functional diarrhea, functional bloating), and compare efficacy among three FMT administration routes.
12 weeks after enrollment

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Adverse events of FMT
Time Frame: From FMT initiation to week 12

The type, frequency and severity of adverse events during transplantation, within 4 weeks (short-term) and within 12 weeks (long-term) after transplantation; compare route-related safety risks.
From FMT initiation to week 12
Change in quality of life assessed by the Irritable Bowel Syndrome Quality of Life (IBS-QOL) questionnaire
Time Frame: Baseline, week 12

The Irritable Bowel Syndrome Quality of Life (IBS-QOL) questionnaire, ranging from 0 to 100. Higher scores indicate worse quality of life. Assessments will be performed at baseline and week 12.
Baseline, week 12
Change in gut microbial alpha-diversity
Time Frame: Baseline, week 12

Gut microbial alpha-diversity (e.g., Shannon index, Chao1 index). Fecal samples will be collected for 16S rRNA sequencing.
Baseline, week 12
Change in quality of life assessed by the Patient Assessment of Constipation Quality of Life (PAC-QOL) questionnaire
Time Frame: Baseline, week 12

The Patient Assessment of Constipation Quality of Life (PAC-QOL) questionnaire, ranging from 0 to 112. Higher scores indicate worse quality of life. Assessments will be performed at baseline and week 12.
Baseline, week 12
Change in gut microbial beta-diversity
Time Frame: Baseline, week 12

Gut microbial beta-diversity, reflecting overall dissimilarity of microbial community composition. Fecal samples will be collected for 16S rRNA sequencing.
Baseline, week 12
Changes in relative abundance of beneficial taxa and microbiota engraftment
Time Frame: Baseline, week 12

Relative abundance of beneficial bacterial taxa and the degree of microbiota engraftment toward donor microbial profiles. Fecal samples will be collected for 16S rRNA sequencing.
Baseline, week 12

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Zhongshan Hospital Xiamen University

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

November 10, 2026

Primary Completion (Estimated)

October 1, 2029

Study Completion (Estimated)

October 1, 2029

Study Registration Dates

First Submitted

October 27, 2026

First Submitted That Met QC Criteria

November 2, 2026

First Posted (Actual)

November 9, 2026

Study Record Updates

Last Update Posted (Actual)

November 9, 2026

Last Update Submitted That Met QC Criteria

November 2, 2026

Last Verified

November 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • MR-35-26-081205

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

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Subscribe