Clinical trials
Microbiome clinical trials
Below are recruiting microbiome clinical trials, each written for real people, not researchers. We’re tracking 346 recruiting studies, each written for real people, not researchers, below.
Recruiting studies
- NCT05296681RecruitingPhase 2
Probiotic trial to help irinotecan work better in metastatic colon cancer
This trial tests a “microbiome health” product (a probiotic-type supplement) to improve how well irinotecan chemotherapy works for people with metastatic colon cancer. It aims to support gut health so treatment can be delivered effectively.
Hamilton, New JerseyAges 18 years+ - NCT05275335Recruiting
Study how germs in burn wounds are best identified
This study compares two ways of finding germs (microbes) in burn wounds: traditional tissue swabs/cultures versus a newer DNA-based method. It may help improve how clinicians understand burn infections and tailor care.
Galveston, TexasAges 18–100 - NCT05288790RecruitingPhase 2
Study how gut chemicals and alcohol affect heart risk in HIV
This Phase 2 study looks at how “microbiome metabolites” (chemicals from gut bacteria) and alcohol may affect heart and blood vessel risk in people living with HIV. If you qualify, you may be asked to follow a study plan to see how these factors change health markers related to cardiovascular disease.
Nashville, TennesseeAges 18–89 - NCT05190848Recruiting
Study of gut microbes and blood chemicals in IgA kidney disease
This trial looks at how bacteria in the gut (microbiome) and substances in the body (metabonomics) relate to IgA nephropathy, a kidney condition. The goal is to understand patterns that may help explain the disease and improve future care.
Guangzhou, GuangdongAges 16–65 - NCT05135351Recruiting
Prebiotics to help your gut health after cancer cell treatment
This trial tests whether taking prebiotics (food for helpful gut bacteria) can improve gut microbiome diversity after your own cancer-cell treatment, like autologous stem cell transplant or CAR-T. It may help your gut ecosystem recover during and after therapy.
Omaha, NebraskaAges 19 years+ - NCT05117125Recruiting
Testing for markers in early ventilator lung infections
This study looks at changes (biomarkers) in the blood or other samples from people on a breathing machine. It may help doctors detect ventilator-associated pneumonia earlier and tailor treatment sooner.
DrammenAges 18 years+ - NCT05133102Recruiting
Collecting saliva to study Barrett’s esophagus over time
This study collects saliva (and, for some people, looks at stomach/esophagus samples) to understand how the mouth and gut “microbiome” changes over time in people with Barrett’s esophagus. It may help researchers find patterns that relate to Barrett’s esophagus and future risk.
Ann Arbor, MichiganAges 18 years+ - NCT05090267Recruiting
Gut-brain treatments for alcohol use and memory changes
This study tests whether gut-brain–targeted treatments (including probiotics and stimulation of a nerve) can improve thinking and inflammation-related health in people who use alcohol. You may be able to join if you have memory/thinking problems and meet specific medical limits, including HIV immune system levels.
Coral Gables, FloridaAges 35–70 - NCT05112614Recruiting
Study links gut bacteria to cancer treatment response
This study looks at how the bacteria in your gut change during cancer treatment (and during some blood stem cell transplants). It may help researchers understand why some people respond differently and guide better future treatment.
Scottsdale, ArizonaAges 18–99 - NCT05020574RecruitingPhase 2
Study how the microbiome may affect breast implant infections
This Phase 2 study looks at whether changes in the body’s “microbiome” (the normal germs in and on the body) are linked to infections after breast surgery with implants. It may help doctors better predict and prevent implant infections in people undergoing mastectomy with immediate implant placement.
San Francisco, CaliforniaAges 18 years+ - NCT04885959Enrolling by invitation
Study how an Asian diet affects gut bacteria and allergy risk in pregnancy
This study looks at whether eating a traditional Asian diet during pregnancy changes gut bacteria and body chemistry in a way that may lower (or change) a baby’s risk of developing allergies. You would follow the diet during pregnancy and be tracked after delivery.
Kota Bharu, KelantanAges 18–40 - NCT04804956Recruiting
Testing gut microbes and metabolites to predict rectal cancer outcomes
This study looks at patterns in the gut microbiome (gut bacteria) and gut chemicals (metabolites) to predict how rectal cancer may do after planned surgery. By understanding these markers, researchers hope to better forecast prognosis and tailor follow-up.
Girona, GironaAges 18–18 - NCT04666402Recruiting
Testing better ways to diagnose early liver disease
This study looks at integrated diagnostic tests to find early liver problems sooner. It may help you (if referred to the community liver clinic) get more timely information about what’s going on.
Manchester, Greater ManchesterAges 18 years+ - NCT04666727Recruiting
Diet and gut microbiome study during screening colonoscopy
This study looks at how a person’s diet (vegetarian vs. omnivorous) affects the germs in the gut and related stool and tissue samples. You may be able to join if you’re getting a screening colonoscopy and meet lifestyle and medication requirements.
Houston, TexasAges 45 years+ - NCT04598022Recruiting
Study how diet affects the gut microbiome in new college students
This study looks at how different eating patterns (vegan, vegetarian, or omnivore) affect the bacteria in your gut over time. It may help researchers understand which diet patterns are linked to healthier gut function.
KielAges 18–25 - NCT04590690Recruiting
Gut microbes and sex risks for kidney stones after weight surgery
This study looks at how gut bacteria (microbes), along with sex, may affect the chance of getting kidney stones after bariatric (weight-loss) surgery. It may help doctors understand who is at higher risk so prevention can be improved.
Chicago, IllinoisAges 18–130 - NCT04264975Recruiting
Using gut microbiome tests and stool transfer in immunotherapy cancer
This trial studies whether changes in gut bacteria can help predict how well immunotherapy works for solid cancers. It also tests whether stool (fecal microbiota) from certain immunotherapy-responding people can improve outcomes for others who are not responding well.
Seoul, SeoulAges 19 years+ - NCT04046900RecruitingPhase 1/Phase 2
Fecal-style transplant of vaginal microbiome for recurring BV
This trial tests whether transplanting “good bacteria” into the vagina can treat recurrent bacterial vaginosis (BV). It may help restore a healthier vaginal bacterial balance and reduce BV episodes.
Boston, MassachusettsAges 18–50 - NCT03325855Recruiting
Fecal transplant registry for patients and donors
This study is a national “registry” that collects information from people who get fecal microbiota transplant (a stool-based treatment) and from people who donate stool. It helps researchers understand who receives these treatments and how they do over time.
Phoenix, ArizonaAges Any age - NCT03932279Recruiting
Study skin microbiome in certain skin diseases
This study looks at the bacteria (microbiome) living on the skin in people with specific skin conditions, and in healthy volunteers. The results may help researchers understand what skin microbes have to do with these diseases.
Chicago, IllinoisAges 18–89 - NCT03819296RecruitingPhase 1
Fecal transplant to treat cancer immunotherapy bowel side effects
This early-phase study tests whether changing your gut bacteria with a fecal transplant can improve diarrhea or colitis caused by cancer immunotherapy. It may help people whose symptoms have not fully settled with standard treatments like steroids and other immune-blocking medicines.
Houston, TexasAges 18 years+ - NCT03577327Recruiting
Study gut and skin germs in vitiligo progression
This study looks at differences in the gut and skin microbiome (the germs living in and on the body) in people with vitiligo and in people without vitiligo. It aims to understand what might be linked to how vitiligo spreads over time.
Chicago, IllinoisAges 18–89 - NCT03633162Recruiting
Study about maternal grandmothers’ effects on babies
This study looks at whether what maternal grandmothers know, do, or influence during a pregnancy is linked to outcomes for grandchildren. You may be included if your grandchild was born at the study hospital and key pregnancy details are available.
Guangzhou, GuangdongAges 36–100 - NCT03437005RecruitingPhase 1
Testing how common skin creams change gut microbes
This study looks at whether commonly used topical (skin) medications change your skin and gut microbial “ecosystem.” It’s an early (Phase 1) pilot study, mainly to see how these treatments affect samples over time.
Sacramento, CaliforniaAges 18 years+
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Common questions
- Are there clinical trials for microbiome?
- Yes. Clin2 currently lists 346 recruiting microbiome 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 microbiome 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 microbiome 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.