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Tundra lists 8 Gut Microbiomes clinical trials. Each listing includes eligibility criteria, study locations, and direct links to research sites in the Tundra directory.
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NCT07873346
Study on Changes in Gut Microbiota, Inflammatory Factors, and Bowel Habits Following Oral Administration of Recombinant B-subunit/Whole Cell Cholera Vaccine in a Community Population
This randomized, placebo-controlled clinical trial aims to investigate the effects of oral cholera vaccine administration on three aspects of gut health in healthy adult community members aged 18 years and older: (1) the composition and function of gut microbiota, (2) serum inflammatory cytokine levels, and (3) bowel habits. The study is designed as an exploratory/basic science investigation to generate hypotheses about how cholera vaccination may influence intestinal health in healthy populations. The findings from this study may provide valuable insights into vaccine-induced changes in the gut microbiome and immune responses, which could inform future research on oral vaccines and their extra-intestinal effects. Participants who agree to take part in this study will be asked to complete the following procedures at two time points: before receiving the study intervention (baseline) and 28 days after completing the full vaccine series. Approximately 200 healthy adults aged 18 years and older from the community will be enrolled in this study. Participants will be randomly assigned in a 1:1 ratio to one of two study groups: Intervention Group (Vaccine Group): receive the oral cholera vaccine according to the manufacturer's recommended schedule; Control Group (Placebo Group): receive a placebo that looks identical to the vaccine but contains no active ingredient. The study will measure the following outcomes to evaluate the effects of cholera vaccine:Gut Microbiota Changes, Serum Inflammatory Cytokine Levels and Bowel Habit Changes.
Gender: All
Ages: 18 Years - Any
Updated: 2026-10-14
1 state
NCT07797803
Grape Impact on Human Gut Microbiome
This is a bio-specimen analysis and dietary intervention study that will examine whether the daily consumption of California table grape powder significantly modulates the gut microbiome and systemic immune profiles in healthy adults. The primary objective is to characterize longitudinal changes in microbial strains, metabolites, and immune markers following a 4-week grape intervention compared to a placebo. Methods include a screening of up to 300 individuals to evaluate pre-specified microbiome eligibility criteria, followed by a randomized, double-blind, placebo-controlled, parallel-group design where up to 40 participants will provide fecal and blood samples for high-resolution metagenomic sequencing and LC-MS/MS metabolomics at baseline, mid-study, and post-washout. Participants who meet the microbiome screening and other study eligibility criteria may be invited to participate in the intervention phase; participation in the screening phase does not guarantee enrollment in the intervention phase.
Gender: All
Ages: 45 Years - 65 Years
Updated: 2026-09-24
1 state
NCT07752589
Microbiota in Neoadjuvant Chemoimmunotherapy for NSCLC
Locally advanced lung cancer (LALC) has poor prognosis despite multimodal therapies. Neoadjuvant chemoimmunotherapy is now standard for resectable stage II-IIIB NSCLC, but patient responses vary. The gut microbiota, a key immune regulator, has been linked to immunotherapy efficacy, with microbial diversity predicting ICI response and fecal microbiota transplantation improving outcomes. While most studies focus on advanced disease, the microbiota's role in LALC during neoadjuvant therapy remains unclear. Exploring its dynamics may uncover novel biomarkers and strategies to optimize treatment
Gender: All
Ages: 18 Years - 80 Years
Updated: 2026-08-07
1 state
NCT07575529
DORA - A Study Using Digital Health Tools/Platform to Explore the Impact of the Consumption of Senior Milk Powder Containing Synbiotics on the Gut micRobiome in Healthy Aging Individuals
The DORA study is a single-arm, open-label, interventional exploratory study designed to evaluate the impact of a synbiotic-containing senior milk powder on the gut microbiome and selected biological, physiological, and digital health parameters in community-living adults in good health. The study enrolls adults aged 40 to 65 years and aims to investigate changes in gut microbial composition, with a primary focus on butyrate-producing microbial taxa, following at least 28 days of study product consumption. Secondary and exploratory objectives include assessment of stool metabolites, blood-based biomarkers, bowel patterns, sleep quality, physical activity, cognitive function, dietary patterns, and quality of life. Approximately 125 participants will be recruited in Singapore to achieve 100 study completers. Following informed consent and screening, participants undergo a baseline observation period of 14 days during which physiological and lifestyle data are collected using wearable digital health devices. Baseline assessments also include blood sampling, stool collection for microbiome analysis, digital imaging and videography, and completion of validated questionnaires. After completion of baseline assessments and collection of the first stool sample, participants initiate consumption of the study product, a senior milk powder containing a defined synbiotic formulation. The study product is consumed twice daily for a minimum of 28 days and up to 35 days to allow completion of study assessments. Participants return for end-of-intervention assessments following the study product phase, including repeat biological sampling, physical and digital assessments, and questionnaires. Stool microbiome profiles and other exploratory outcomes are compared between baseline and post-intervention time points. This exploratory study is intended to generate feasibility data and hypotheses regarding the effects of synbiotic nutritional intervention and the integration of biological and digital health data in the context of healthy aging.
Gender: All
Ages: 40 Years - 65 Years
Updated: 2026-08-03
NCT07366047
Autologous Probiotics in Patients With Defunctioning Ileostomy Following LAR for Rectal Cancer
Rectal cancer patients who received low anterior resection combined with ileostomy may effectively reduce the probability of anastomotic leakage after surgery. However, due to the long-term semi-abandoned state of the distal colon, the probability of bowel dysfunction after ileostomy closure is very high. The incidence of low anterior resection syndrome (LARS) exceeds 70%, which is twice that of those who did not receive a preventive stoma. The main reasons include postoperative anatomical structure alteration, nerve damage, pathological changes of the colorectal mucosa, and gut microbiota variation, etc. The application of probiotics can significantly improve the bowel function of these patients. In this study, in order to enhance the colonization effect of probiotics, autologous probiotics will be applied to treat patients with defunctioning ileostomy. The primary outcome is the occurrence of major LARS after 6 months of the treatment.
Gender: All
Ages: 18 Years - 80 Years
Updated: 2026-01-26
NCT06833593
Antimicrobial Combination Therapy for Treatment of Enterococcus Faecalis Bacteremia
Prospective, multicenter, national, observational pharmacological study on the evaluation of efficacy of appropriate monotherapy vs combination treatment for non-complicated Enterococcus faecalis (EF) bloodstream infection (BSI) and identification of gut microbiota fingerprint of patients with EF-BSI correlated to antimicrobial treatment and clinical outcome
Gender: All
Ages: 18 Years - Any
Updated: 2025-12-03
3 states
NCT06959043
Therapeutic Strategies for Type 2 Diabetes Based on Lifestyle Changes: Plant-based Diet and Physical Exercise
The study evaluates the impact of a strict vegetarian diet combined with regular physical exercise and the use of probiotics on metabolic, inflammatory, and epigenetic parameters in patients with type 2 diabetes. It aims to determine the influence of these interventions on gut microbiota, glycemic control, body composition, insulin resistance, and quality of life.
Gender: All
Ages: 45 Years - 70 Years
Updated: 2025-05-18
1 state
NCT06710574
Multimodal Image Technologies Investigate the Role and Mechanism of Probiotics in Improving RBD with Parkinson's Disease
Rapid eye movement sleep behavior disorder (RBD) is important non-movement feature, and also the important risk factor of Parkinson's disease (PD). In our previous work, we found that the movement features and RBD of PD patients improved after taking probiotics. The later was not reported before and the mechanism not clear. To investigate its role and mechanism, we plan to enroll patients of PD-RBD, idiopathic RBD, and healthy control, collect data of multimodal image technology before and after probiotic treatment,including resting state functional MRI,1H-MRS,123I-MIBG; analyze these data with clinical features, including UPDRS -III score, RBD-HK score , as well as the bacteria abundance and level of glutamate,GABA in blood and stool. Then, construct PD mouse model by fecal transplantation of PD patient, give or not give mouse probiotics treatment, and detect the level of glutamate, GABA, and so on, as well as α-synuclein of each brain area of each group, to explore the role and mechanism of probiotics in improving RBD and movement disorder of PD.
Gender: All
Ages: 40 Years - 85 Years
Updated: 2024-12-02