Medical Information Only. Consult your healthcare provider before considering clinical trial enrollment.

ClinicalTrials.gov 16 recruiting now official registry

Gut Microbiome clinical trials

Every US clinical trial registered for Gut Microbiome — phase mix, recruiting status, and the sponsors running them, straight from the NIH ClinicalTrials.gov registry.

23 US clinical trials · 16 currently recruiting

The research picture

Gut Microbiome has 23 registered US clinical trials, 16 of them open to new participants right now — about 70% of the total.

16
recruiting participants now
70%
of trials open to enrollment
1
in Phase 3–4 (later-stage)
2
top sponsor: Seeding

Counts reflect the public ClinicalTrials.gov registry as last mirrored by PlainTrial. Status and phase are reported by each study's sponsor. This is reference information, not medical advice.

Active & Recent Trials

RECRUITING 4,000 participants

Fecal Microbiota Transplant National Registry

American Gastroenterological Association

NCT03325855

RECRUITING NA 250 participants

Flourish: Exploring the Early Infant Gut Microbiome

Seeding

NCT07333482

RECRUITING 250 participants

A Study to Explore the Role of Gut Flora in COVID-19 Infection

ProgenaBiome

NCT04359836

RECRUITING NA 150 participants

Early Avocado Exposure on Development and the Gut Microbiome in American Hispanic Infants

Arizona State University

NCT06876935

RECRUITING 133 participants

The Gut Microbiome and Serum Metabolites As a Biological Mechanism Underlying Pain in Kidney Transplantation

University of Illinois at Chicago

NCT06206486

RECRUITING NA 80 participants

The Path Study: Cognitive and Inflammation Targeted Gut-brain Interventions in Alcohol; Probiotics, Alcohol, Transcutaneous Vagus Nerve Stimulation, and HIV Study

University of Florida

NCT05090267

RECRUITING NA 60 participants

The Effect Cranberry-Based Products on the Female Microbiome

Ocean Spray Cranberries

NCT07109713

RECRUITING Phase 1 60 participants

Curcumin and Retinal Study

Texas Tech University Health Sciences Center

NCT05774704

RECRUITING NA 60 participants

Effects of Mango or Low-Fat Cookie Consumption on Gut Health, and Its Relationship With Mental, Sexual and Skin Health

San Diego State University

NCT06800833

RECRUITING NA 50 participants

Enhanced Nutritional Optimization in LVAD Trial

Columbia University

NCT05655910

RECRUITING NA 40 participants

How a Single Workout Affects Gut Bugs in Women With Different Fitness Levels and Body Types

George Washington University

NCT06691100

RECRUITING 35 participants

Impact of Gut Microbiome on Metabolic and Bowel Function During the First Year After Spinal Cord Injury

University of Alabama at Birmingham

NCT05670288

RECRUITING NA 30 participants

Feasibility and Potential Efficacy of Herbs and Spices for Improving Dietary Quality in College Students: A Pilot Study

University of Nevada, Las Vegas

NCT07082348

RECRUITING 30 participants

Gut Microbiome and Treatment for Gynecological Cancer Patients Receiving Immunotherapy

Viome

NCT04957511

RECRUITING Phase 4 20 participants

Understanding the Efficacy of Dietary Supplement on Fungal Mycobiota in Healthy Volunteers: A Pilot Study

Weill Medical College of Cornell University

NCT06433310

RECRUITING NA 20 participants

Garden-fresh Foods and Gut Microbiomes

University of Oregon

NCT06506786

ACTIVE NOT RECRUITING NA 267 participants

Effects of Complementary Feeding on Infant Growth and Gut Health

University of Colorado, Denver

NCT05012930

ACTIVE NOT RECRUITING NA 126 participants

Gut Microbe Composition, Exercise, and Breast Breast Cancer Survivors

University of Alabama at Birmingham

NCT04088708

ACTIVE NOT RECRUITING NA 100 participants

Infant Restore: Efficacy of Microbiome Analysis and Education

Seeding

NCT06424691

ACTIVE NOT RECRUITING NA 40 participants

Low Sugar Protein Pacing, Intermittent Fasting Diet in Men and Women

Skidmore College

NCT04327141

COMPLETED NA 40 participants

Salmon Intake and Gut Health in Adults

University of Colorado, Denver

NCT04792216

COMPLETED NA 32 participants

Yogurt and GI Health

USDA, Western Human Nutrition Research Center

NCT05931471

COMPLETED NA 14 participants

Fiber Blends and Gut Microbiota (FB)

Washington University School of Medicine

NCT04101344

Phase Distribution

PhaseTrial count
Phase 1 1
Phase 4 1

Source: ClinicalTrials.gov, National Library of Medicine. Data is informational only.

Reading the Gut Microbiome Trial Landscape

ClinicalTrials.gov lists 23 US studies indexed under Gut Microbiome, and 16 of those are currently open to recruitment — roughly 70% of the total volume on the registry. That ratio is a useful proxy for activity level: a high share of recruiting studies often signals that research interest is current and that new enrollment opportunities are appearing, while a low share typically means the field is dominated by completed or follow-up work where most participant spots have already been filled. These counts reflect the public registry only and include studies at every stage of design, so they should be read as an index of research attention rather than as a measure of treatment availability.

The phase distribution for Gut Microbiome shows 1 late-stage studies (Phase 3 and Phase 4 combined) alongside 1 earlier-phase entries (Phase 1 through Phase 2). Phase 1 and Phase 2 studies focus on early safety signals, dosing, and preliminary effect, while Phase 3 studies are typically the larger efficacy and safety trials submitted toward regulatory review, and Phase 4 studies follow approved interventions in real-world use. A condition weighted toward later phases often reflects a mature research pipeline with several interventions already close to or past approval, whereas a heavier early-phase tilt suggests the field is still exploring new mechanisms and candidate approaches.

Top sponsor activity for Gut Microbiome is led by Seeding with 2 indexed trials, alongside 9 other organizations in the top contributor list. The list on this page surfaces up to 23 of the most relevant recent and active entries, ordered with recruiting studies first so practical options are visible. All figures are derived from the public ClinicalTrials.gov dataset maintained by the National Library of Medicine and are reproduced here for reference. Inclusion of a trial, sponsor, or intervention on this page is neither an endorsement nor a recommendation — eligibility, protocol changes, and site-level status can shift frequently, so always verify current details on ClinicalTrials.gov and consult a qualified healthcare provider before acting on anything you see here.

Frequently Asked Questions

How many clinical trials are there for Gut Microbiome?

PlainTrial tracks 23 US clinical trials for Gut Microbiome, of which 16 are currently recruiting participants. Data sourced from ClinicalTrials.gov.

How do I find a recruiting trial for Gut Microbiome?

Use the trial list above filtered by "Recruiting" status, or visit our trial finder at /recruiting to search by condition and state. Always discuss trial participation with your healthcare provider before enrolling.

Is this data current?

Data is sourced from ClinicalTrials.gov and reflects our most recent data pull. Trial status may have changed since then. Always verify current information at ClinicalTrials.gov before making decisions about participation.

Related

Disclaimer: This information is provided for informational purposes only and does not constitute professional advice. Data is sourced from ClinicalTrials.gov (National Library of Medicine). Consult a qualified professional before making decisions based on this data.

Source: ClinicalTrials.gov (NIH/NLM) ClinicalTrials.gov AACT registry · 2026 Trial counts and statuses sourced from ClinicalTrials.gov. Sponsor counts include both industry and federal/academic sponsors.

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