Clinical trials
Microbiome clinical trials
Below are recruiting microbiome clinical trials, each written for real people, not researchers. We’re tracking 351 recruiting studies, each written for real people, not researchers, below.
Recruiting studies
- NCT07623902Recruiting
Testing a Tongue Scan to Detect Colorectal Polyps
This study tests whether a new tongue-scanning tool called Gixam can help find advanced colorectal polyps in people with negative stool tests. If it works, it might offer a simpler screening option alongside colonoscopy.
Orlando, FloridaAges 45–84 - NCT07453823Recruiting
Synbiotic for gut health in overweight adults
This trial tests a combination supplement (a synbiotic) to see if it can improve gut function and gut bacteria in middle-aged and older adults who are overweight and have constipation. If eligible, you take the supplement daily and report how your digestion feels.
Cork, BlackpoolAges 50–70 - NCT06724133Recruiting
Mouth bacteria and colon polyps study
This study looks at the bacteria in your mouth and how they might be linked to colon polyps. Researchers want to see if certain mouth bacteria affect the body's immune system and increase the risk of polyps.
Shanghai, Shanghai MunicipalityAges 18 years+ - NCT07052409Enrolling by invitation
Protecting HIV-exposed infants from severe infections
This trial studies ways to protect babies who were exposed to HIV before birth but are not infected themselves. It aims to find better interventions to prevent severe infections in these infants.
JohannesburgAges 6 months–45 years - NCT07082348Recruiting
Herbs and spices for better diet in college students
This study tests whether adding herbs and spices to your daily meals can help improve your diet quality over a short period. It is designed for college students who feel their eating habits could be healthier.
Las Vegas, NevadaAges 18–39 - NCT06423508Recruiting
Testing stool storage methods and gut bacteria differences
This trial will study how different storage methods affect stool samples for gut bacteria analysis. It aims to understand differences in gut bacteria between people over time. Participation involves providing stool samples.
Vienna, State of ViennaAges 18–70 - NCT06466434RecruitingPhase 2
Prebiotic diet to boost immunotherapy for melanoma
This trial tests whether a special prebiotic diet can help your body's bacteria (microbiome) better respond to standard immunotherapy for advanced melanoma that cannot be removed by surgery. If you are starting your first immunotherapy, you may be able to join.
Houston, TexasAges 18 years+ - NCT04611217Recruiting
Testing fiber to change gut bacteria and help with fullness
This study tests how eating different amounts of dietary fiber affects your gut bacteria and how full you feel. You may be able to help researchers understand whether fiber can support appetite and metabolic health.
Columbia, MissouriAges 20–55 - NCT07443280Recruiting
Gut health supplement study for dialysis patients
This trial tests whether a special blend of probiotics and prebiotics (called a synbiotic) can improve gut health and reduce harmful waste products in the blood for people on hemodialysis.
Taichung, Wuqi DistrictAges 18 years+ - NCT06433310RecruitingPhase 4
A dietary supplement's effect on gut fungi in healthy adults
This study tests whether a dietary supplement (L-phenylalanine) can affect the natural balance of fungi in the gut. Healthy volunteers take the supplement for a short time, and researchers check how it changes their gut fungi.
New York, New YorkAges 18 years+ - NCT05670262Recruiting
Study vitamin D and gut bacteria in childhood allergies
This study looks at how gut bacteria (microbiome) and vitamin D levels in newborns may influence whether children develop allergies. It starts with newborn babies and aims to better understand what early factors could predict allergic diseases.
TaichungAges birth–1 year - NCT06310239Recruiting
Microbiome Study for Adults Having Surgery
This study looks at how your body’s natural bacteria (called the microbiome) may change after surgery. Researchers want to learn about the gut and skin bacteria of adults who are having a procedure, which could help improve recovery in the future.
Bethesda, MarylandAges 18–75 - NCT07311083Recruiting
Lifestyle program for triple-negative breast cancer patients
This study tests a lifestyle program (diet, exercise, and support) for women with triple-negative breast cancer who are getting chemotherapy plus immunotherapy before surgery. The goal is to see if healthy habits can help during treatment.
Essen, North Rhine-WestphaliaAges 18–75 - NCT06800833Recruiting
Mango or cookie study for gut, mental, sexual, and skin health
This study is testing whether eating mangoes or low-fat cookies every day for 4 weeks can improve your gut health, and in turn affect your mood, sex life, and skin. If you are generally healthy, not pregnant, and not taking certain medications or supplements, you may be able to join.
San Diego, CaliforniaAges 18–50 - NCT06802276Recruiting
Smart underwear measures gas from diet
This study tests special underwear that can measure gas produced by digestion after eating different foods. Researchers want to see if the underwear can track how diet affects gas production.
Aurora, ColoradoAges 18 years+ - NCT06709976Enrolling by invitation
Fertility test and IVF study
This study looks at whether a special test called ReceptIVFity, which checks the health of the vagina, can help improve pregnancy rates in women undergoing IVF or ICSI. If you are planning IVF or ICSI and are of European origin, you might be able to join.
Rotterdam, South HollandAges 18–42 - NCT07388264Recruiting
Probiotic for bloating and gut health
This study tests a probiotic (a good bacteria) called Weizmannia coagulans to see if it helps reduce bloating and improves gut health. Researchers will check how your digestion changes by looking at your stool and gut bacteria.
Saint Charles, MissouriAges 18–50 - NCT06833593Recruiting
Antibiotic combinations for enterococcus blood infection
This study looks at whether using two or more antibiotics together works better than one alone for a specific type of blood infection caused by Enterococcus faecalis bacteria. The goal is to find the safest and most effective way to treat this infection and improve outcomes for patients.
Bologna, BolognaAges 18 years+ - NCT07200531Recruiting
Can therapy change gut bacteria in women?
This trial studies whether psychotherapy can affect the bacteria living in your gut. It is for women aged 19 to 53 who are not pregnant, breastfeeding, or already in regular therapy.
Omaha, NebraskaAges 19–54 - NCT07189390RecruitingPhase 2
Probiotic study for infants who had antibiotics at birth
This study tests whether giving a probiotic (a 'good' bacteria) to babies who received antibiotics shortly after birth can help their developing gut and immune system. Participants will receive a daily probiotic or placebo for about 6 weeks, and their health will be monitored.
Adelaide, South AustraliaAges Up to 4 weeks - NCT07093463Recruiting
Colon-delivered Vitamin B2 for Gut Health
This trial tests whether a special form of vitamin B2 (riboflavin) delivered to the colon can improve gut health in people with mild to moderate bowel complaints. The study compares the effects of this supplement to a standard diet add-on (inulin) and looks at changes in gut bacteria and symptoms.
Berlin, State of BerlinAges 50–70 - NCT06941090Recruiting
Stool sample collection for nutrition gut health study
This study asks participants of the NutriNet-Santé health study to provide a stool sample. Researchers want to understand how diet and gut bacteria affect health.
BobignyAges 18 years+ - NCT07585474Enrolling by invitation
Gut Health During Long Travel for Football Players
This study looks at how long airplane trips affect the gut bacteria in professional male football players. Researchers will track changes in your digestive system during pre-season travel to understand if travel impacts your gut health.
Nashville, TennesseeAges 18–40 - NCT07614542Recruiting
Understanding Gut Health and Hormones in Aging Women
This study explores how your gut bacteria and hormones change as you age. Researchers will collect stool and blood samples and ask about your health to better understand women's aging.
LisbonAges 40–64
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Common questions
- Are there clinical trials for microbiome?
- Yes. Clin2 currently lists 351 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.