Clinical trials
Microbiota clinical trials
Below are recruiting microbiota clinical trials, each written for real people, not researchers. We’re tracking 408 recruiting studies, each written for real people, not researchers, below.
Recruiting studies
- NCT07400354Recruiting
PD-1 drug plus chemo for advanced stomach cancer based on gut bacteria
This trial tests if adding a PD-1 immunotherapy drug to standard chemotherapy works better for advanced stomach cancer, and looks at how your gut bacteria may affect treatment. It is for people who have not had chemotherapy before and are starting their first treatment.
Shanghai, Shanghai MunicipalityAges 18 years+ - NCT07401680RecruitingPhase 1
Stool transplant for active ulcerative colitis
This trial tests whether a stool transplant (fecal microbiota transplantation) can help manage active ulcerative colitis. You would receive a transplant from a healthy donor to see if it improves your symptoms.
Calgary, AlbertaAges 18 years+ - NCT07490054RecruitingPhase 1
Fecal transplant for chronic heart failure
This trial tests whether transferring healthy gut bacteria (fecal microbiota transplant) can help people with chronic heart failure feel better and improve their heart function.
New York, New YorkAges 18 years+ - NCT07550023Recruiting
How Different Dietary Fats Affect Your Gut Health
This study examines how different types of dietary fats influence the bacteria in your gut and how your body processes nutrients. By participating, you'll help researchers understand the link between fat intake and digestive health in healthy adults.
GlasgowAges 20–50 - NCT07619560Recruiting
Probiotic Cocktail to Slow Early Parkinson's Disease
This study tests whether a special blend of probiotics (good bacteria), an amino acid called tryptophan, and branched-chain amino acids can help slow the progression of early-stage Parkinson's disease. The idea is that these supplements may work through your gut bacteria to help protect your brain.
TaipeiAges 30–85 - NCT06645223Enrolling by invitation
Gut bacteria and pancreas function in diabetes
This study looks at how gut bacteria relate to the pancreas's ability to make insulin in people with different blood sugar levels. It may help researchers understand why some people develop diabetes and how to better treat it.
BeijingAges 18–80 - NCT06824493Recruiting
How Braces Affect Mouth Bacteria and Saliva
This study looks at how braces (orthodontic treatment) change the bacteria and proteins in your mouth. Healthy volunteers who have never had dental work or cavities are needed to provide saliva samples before and during treatment.
Xi'an, ShaanxiAges 6–18 - NCT07724522Recruiting
Prebiotic Fiber for Irregular Periods in Women
This study tests whether taking a prebiotic fiber (inulin) can help women who are in the later years of their reproductive life (before menopause) and have irregular periods. You may be eligible if you are overweight, have irregular cycles, sit a lot, and do not exercise much.
Washington D.C., District of ColumbiaAges 40–55 - NCT06474234RecruitingPhase 2
Probiotic for Gut Health in Young Children
This study tests whether a probiotic (a 'good bacteria' supplement) can help balance the gut bacteria in young children. Your child may be able to join if they are healthy, under 7, and haven't taken probiotics or antibiotics recently.
Cheras, Kuala LumpurAges 1 month–7 years - NCT07243574Recruiting
Night owl sleep study: how sleep affects gut bacteria
This study looks at how different sleep patterns (short or long sleep) affect the bacteria in your gut. You will wear a sleep tracker, record your sleep and diet, and provide stool samples to see if changing your sleep schedule changes your gut health.
Miami, FloridaAges 20–40 - NCT03223077Recruiting
Study of gut germs in new Campylobacter stomach illness
This trial studies how your gut germs (microbiome) and gut lining change during a new bout of Campylobacter infection. It may help researchers understand what drives symptoms and how the gut recovers.
Rochester, MinnesotaAges 18–80 - NCT05758961Recruiting
Study of gut bacteria in adults living in France
This study looks at the types of bacteria in your gut (gut microbiota) by analyzing a stool sample. It aims to better describe typical gut bacteria patterns in France and may help researchers understand links to health.
BobignyAges 18 years+ - NCT05449119Recruiting
Study links gut health, diet, and thinking and movement in seniors
This study looks at how differences in gut bacteria and nutrition may relate to changes in thinking and movement in people over 75 who have a reduced appetite (“small eaters”). It may help doctors better understand what could be contributing to these problems and how nutrition might play a role.
DijonAges 75 years+ - NCT04418258Recruiting
Test a new scope suction catheter during endoscopy
This study tests a special aspiration (suction) catheter used during an upper GI endoscopy to see how well it works during routine care. It may help doctors improve how they clear fluid or residue during the procedure.
Los Angeles, CaliforniaAges 18–85 - NCT04373473RecruitingPhase 2
Oral stool treatment to prevent ulcerative colitis flare-ups
This study tests whether taking freeze-dried (lyophilized) donor stool material by mouth can help prevent ulcerative colitis from coming back or causing intestinal inflammation. Participants are in remission and stay on their usual treatment while receiving the study product.
Houston, TexasAges 18 years+ - NCT06957626Recruiting
Predicting polyp return after removal
This study aims to develop a tool using gut bacteria and metabolites to predict if high-risk colon polyps will come back after removal. If you are between 40 and 75 and have had certain types of colon polyps removed, you may be able to help us build better prediction methods.
BeijingAges 40–75 - NCT06298409RecruitingPhase 1
Rifaximin for SIBO: Gut Bacteria Study
This study tests how Rifaximin (a medicine for SIBO) affects the bacteria and other substances in your gut. You'll swallow a small capsule that collects samples as it travels through your digestive system, so researchers can see how your gut changes during treatment.
Mountain View, CaliforniaAges 18–80 - NCT06001333Recruiting
Fecal transplant to clear superbugs from the gut
This study tests whether a fecal transplant (FMT) can remove certain antibiotic-resistant bacteria from your gut. It might help people who carry superbugs like CPE or VRE but aren't currently on antibiotics.
Chuncheon, Gangwon-doAges 20 years+ - NCT06037421Recruiting
Bacteria in breast milk of NICU mothers
This study looks at the bacteria naturally found in breast milk. Researchers want to learn more about the germs in milk from mothers whose babies are in the neonatal intensive care unit.
Corbeil-Essonnes, FranceAges 1 hour+ - NCT05319067Recruiting
Gut bacteria study in toddlers on long-term reflux antibiotics
This study compares gut bacteria (microbiome) in toddlers who take an antibiotic to prevent urine infections for vesicoureteral reflux, versus other similar children. It may help researchers understand how long-term antibiotic use and reflux affect gut health and future risk.
MontpellierAges 1–3 - NCT05473793Recruiting
Dried vegetables study for constipation and gut bacteria
This study tests whether eating a dried vegetable can improve bowel habits and change gut bacteria. It may help people who feel their bowel function is not working well and have hard or infrequent stools.
Wageningen, GelderlandAges 20–80 - NCT06645535Enrolling by invitation
Gut Bacteria and Blood Substances in Stiff Heart Failure
This study looks at how bacteria in your gut and certain substances in your blood relate to a type of heart failure called HFpEF (where the heart is stiff and doesn't relax well). It may help doctors understand the condition better and find new ways to treat it.
Naning, JiangsuAges 18 years+ - NCT05071131Recruiting
Inulin supplement to improve gut health in kidney disease
This trial studies whether taking inulin—a dietary fiber—can improve gut bacteria and the gut barrier in people with end-stage kidney disease on hemodialysis. It may help reduce gut-related problems that can affect overall health in kidney disease.
BerlinAges 18–75 - NCT05054361Recruiting
Study gut immunity changes in children with type 1 diabetes
This study looks at how a type of immune cell (MAIT cells) and the gut (microbiota and gut lining) change around the time type 1 diabetes starts in children. It may help researchers understand why type 1 diabetes begins and how the gut and immune system are connected.
AntonyAges 1–15
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Common questions
- Are there clinical trials for microbiota?
- Yes. Clin2 currently lists 408 recruiting microbiota studies from the U.S. registry, each rewritten for real people, not researchers, so you can see what it’s testing and who it’s for.
- How do I know if I qualify for a microbiota trial?
- Each study lists its eligibility criteria — rules about age, diagnosis, and prior treatments. On every Clin2 trial page we explain these in words written for real people and offer a short, optional pre-screen for a fit read. The study team makes the final decision.
- Does it cost anything to join a microbiota trial?
- Using Clin2 is always free. Many trials cover the cost of the study treatment and related visits; some reimburse travel. The study team explains exactly what’s covered before you decide.
Related conditions
Clin2 helps you find and understand clinical trials and does not provide medical advice. Study data comes from ClinicalTrials.gov. Talk with your doctor about whether a specific trial is right for you.