Clinical trials
Microbiota clinical trials
Below are recruiting microbiota clinical trials, each written for real people, not researchers. We’re tracking 376 recruiting studies, each written for real people, not researchers, below.
Recruiting studies
- NCT04022109Recruiting
Check gastric cancer using breath chemical signals
This study looks at chemical signals in your breath to help screen for or understand gastric (stomach) cancer. It may help doctors improve earlier detection, or better sort out who may need further tests.
São PauloAges 18 years+ - NCT05698862Recruiting
Study how gut bacteria affect brain and behavior
This study looks at how gut bacteria may influence brain function and behavior, through a chemical called GABA. It may help researchers understand brain–gut links, though it is not yet a treatment trial.
ReadingAges 18–50 - NCT03855657Recruiting
Biobank study of gut microbes, genes, and blood chemistry
This study collects samples to learn how gut microbes, genetics, and body chemistry may relate to Crohn’s disease or ulcerative colitis. Your information and samples may help researchers understand disease patterns, but it does not test a new drug.
Hong KongAges 18 years+ - NCT06001619RecruitingPhase 4
Prostate medication, metabolism, and gut bacteria
This study looks at how prostate medication affects your metabolism and the helpful bacteria in your gut. It may help explain how these drugs work and how they affect your body.
TurkuAges 18 years+ - NCT06050148RecruitingPhase 2/Phase 3
Fecal Transplant to Prevent Repeat Urinary Tract Infections
This trial tests whether a fecal microbiota transplant (a procedure that transfers healthy bacteria from a donor's stool into your gut) can help prevent repeat urinary tract infections in women who have frequent infections.
HelsinkiAges 18–90 - NCT06106698Recruiting
Washed microbiota transplant for C. diff infection
This trial tests a treatment called washed microbiota transplantation (WMT) for people with a C. diff infection that causes diarrhea. WMT uses processed donor bacteria to help restore healthy gut balance and fight the infection.
Nanjing, JiangsuAges 3–100 - NCT05024188Recruiting
Gut bacteria and exercise performance study
This study looks at how the bacteria in your gut might affect your physical fitness and exercise ability. You would need to be a regular exerciser and take some antibiotics as part of the study.
RehovotAges 20–55 - NCT06266897Recruiting
Endometriosis and tissue bacteria study
This study looks at how tiny organisms (microbiota) inside the uterus and pelvis may be linked to endometriosis. If you are having surgery for endometriosis, researchers will collect tissue samples to compare the bacteria in your body with your symptoms.
Guangzhou, GuangdongAges 18–52 - NCT05654753RecruitingPhase 2/Phase 3
Fecal transplant for stubborn axial spondyloarthritis
This trial tests whether transplanting healthy stool bacteria (fecal microbiota transplantation) can reduce symptoms in people with axial spondyloarthritis (including ankylosing spondylitis) who are not improving enough with standard medicines. If you qualify, you may receive study capsules containing processed bacteria and be closely monitored for safety and symptom changes.
Boulogne-BillancourtAges 18–75 - NCT03373721Recruiting
Compare gut microbes in preterm vs full-term babies
This study looks at differences in the gut bacteria of babies born early (preterm) compared with babies born full-term. It may help researchers understand how early birth affects early health and gut development.
ShanghaiAges 1 day–4 months - NCT05786404RecruitingPhase 1
Fecal transplant study for people with active ulcerative colitis
This trial tests whether transplanting stool bacteria (called fecal microbiota transplantation, or FMT) can improve symptoms in people with active ulcerative colitis. You may be able to help test a new approach for restoring gut bacteria, while receiving standard ulcerative colitis care from your doctor.
Houston, TexasAges 18 years+ - NCT04117321Recruiting
Study of mother-to-baby gut germs and baby health
This study looks at how germs in a mother can be passed to her baby and whether that affects the baby’s health. If you join, your baby (and the other parent or legal guardian) may be asked to share consent so researchers can follow the pregnancy and early life.
Hong Kong, Hong KongAges Any age - NCT07848594Recruiting
Temperature-regulating bed cover for sleep and health
This study tests whether a special temperature-regulating bed cover can improve sleep quality and reduce body inflammation, and how it affects gut health and your body's internal clock. You will use the bed cover and other devices at home, and provide blood and stool samples to see how your body responds.
Newton Center, MassachusettsAges 45 years+ - NCT07846254Recruiting
Daily fiber supplement for a healthy gut
This study tests whether a daily soluble fiber supplement can improve the balance of bacteria in your gut. If you are generally healthy and have normal bowel habits, you may be able to join and help researchers learn more about gut health.
Addison, IllinoisAges 18–60 - NCT07828093Enrolling by invitation
Effects of agave on performance and gut health in athletes
This trial studies whether eating agave, a natural sweetener, can improve physical performance and support healthy gut bacteria in athletes. If you are an athlete, this could help you understand how diet affects your training and digestion.
Yautepec, MorelosAges 18–40 - 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 - NCT07818109Enrolling by invitation
Risk factors for carrying resistant gut bacteria in the community
This study looks at why some healthy people carry resistant bacteria in their gut (called ESBL-producing bacteria). Researchers will collect stool and urine samples and ask about your daily life to find possible risk factors. You won't receive any treatment, but your participation can help scientists understand how to prevent the spread of these bacteria.
Buenos Aires, Buenos Aires F.D.Ages 18 years+ - NCT07816536Recruiting
How gut bacteria change with exclusive liquid nutrition in children
This study looks at how giving children complete liquid nutrition (exclusive enteral nutrition) affects the good bacteria in their gut. It may help us learn how this treatment works for children who rely on it.
NantesAges 1–16 - NCT07808086Recruiting
Tumor bacteria in triple-negative breast cancer treatment response
This study looks at the bacteria found in the tumor to see if they affect how well chemotherapy or immunotherapy works in treating triple-negative breast cancer. The goal is to find ways to predict treatment response and improve care.
PaviaAges 18 years+ - NCT06479928Recruiting
How environment and gut bacteria affect early life
This study looks at how things in the environment (like diet, pollution, or lifestyle) and the bacteria in a baby's gut affect health early in life. It is for pregnant women who are in their last month of pregnancy and their newborns.
BeijingAges 1 day–2 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+ - NCT06265246Recruiting
Milk and yogurt for stronger bones in young adults
This study tests whether adding milk and yogurt to your diet can improve bone health and body composition. If you're a young adult with low calcium intake, you may qualify to join.
Saskatoon, SaskatchewanAges 19–30 - NCT03787771Recruiting
Fecal transplant registry for donors and recipients
This is a registry that collects information from adults who either receive fecal microbiota transplant (FMT) or plan to receive it, and from people who have donated—or plan to donate—stool for FMT. It helps researchers understand who participates in these gut-microbiome treatments in real life.
Hong KongAges 18 years+ - NCT07755800Enrolling by invitation
Arginine toothpaste for gum health in periodontitis patients
This study tests whether an arginine-containing toothpaste improves gum health in people with treated periodontitis during their maintenance care. It may reduce gum inflammation and promote better bacterial balance below the gumline.
Iowa City, IowaAges 18–95
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Common questions
- Are there clinical trials for microbiota?
- Yes. Clin2 currently lists 376 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.