Clinical Trials

The purpose of this study is to evaluate the effectiveness and safety of vibegron, a beta-3 adrenergic receptor (β3-AR) agonist, in the treatment of pain associated with irritable bowel syndrome (IBS) due to IBS with predominant diarrhea (IBS-D) or mixed episodes of diarrhea and constipation (IBS-M).

To evaluate the safety and effectiveness of oral nutritional therapy Serum-Derived Bovine Immunoglobulin (SBI) on nutritional status, epithelial barrier function, and mucosal expression of pivotal genes including tight junction, secretory mechanisms, tissue repair proteins and chemokines in subjects with IBS-D.

This study is being done to see if Lyrica helps people with irritable bowel syndrome.

This study will evaluate obesity as a comorbidity in a population of patients with irritable bowel syndrome (IBS), and assess this cohort for vitamin D-deficiency. It will also determine whether alterations in the fecal microbiome and metaproteome, associated with vitamin D deficiency or other factors, underpin obesity-IBS comorbidity.

The purpose of this study is to evaluate symptom response to a low FODMAP diet provided by different educational programs, assess adherence to the low FODMAP diet provided by different educational programs, and to measure knowledge retention for different low FODMAP educational programs.

The purposes of this study are to to evaluate the use of IgG antibody guided dietary restrictions, based on the Biomerica InFoods® IBS ELISA, in the management of patients diagnosed with Irritable Bowel Syndrome (IBS).

The primary objectives of this study are to explore the therapeutic effect of eluxadoline in treating IBS-D in pediatric patients 12-17 years of age, to evaluate the pharmacokinetics of eluxadoline in pediatric patients with IBS-D, and to evaluate the safety and tolerability of eluxadoline in pediatric patients with IBS-D.

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The purpose of this study is to assess how common bile acid malabsorption is in patients that have diarrhea predominant irritable bowel syndrome, by measuring blood samples for bile acids and abnormal levels of regulating hormones.

The purpose of this study is to identify twin pairs where one or both the siblings have Irritable bowel syndrome (IBS) based on the Rome III criteria and to determine fecal microbiota changes in concordant and discordant twins with IBS.

The purpose of this study is to find out if having a stomach tube placed as a baby is connected to having greater chances of stomach or intestine problems later in life.

A study of the efficacy and safety of Lubiprostone in subjects diagnosed with IBS-M/IBS-U.

The purpose of this study is to evaluate gastric, small-bowel, and colonic transit in subjects with IBS-C and IBS-D treated with multiple (three times daily) doses of olorinab (50 mg).

The purpose of this study is to test gluten supplementation for four weeks, to see if it increases small intestinal permeability and accelerates colonic transit in patients who have irritable bowel syndrome with diarrhea (IBS-D) or functional diarrhea (FD) who are HLA-DQ2 positive.

To better understand the relationship between gut barrier function and the symptomatology and pathophysiology of IBS.

The investigators' hypothesis is that therapy with Colesevelam, reduces fecal bile acid excretion in patients with IBS-diarrhea with prior evidence of increased fecal 48 hour total bile acid excretion. The investigators aim to study the ability of the HPLC assay for fecal bile acids to demonstrate responsiveness after treatment with Colesevelam.

Microbiota from fecal samples from IBS-D patients, in combination with vitamin D supplementation added to our 3-D immunocompetent intestinal models will establish a high fidelity disease model to achieve our long-term goal to understand the relationship between gut microbiome, vitamin D levels, host gene expression and IBS-D symptoms that could ultimately be used as a testing platform for treatment and prevention.

The purpose of this study is to determine if people with diarrhea predominant IBS (IBS-D) from the community are interested in making dietary modifications to control their symptoms.  Also to determine if people with IBS-D from the community have tried dietary modifications to control their symptoms and if they have, which diets they have tried.

The purpose of this study is to understand the role of genetics (inherited genes from biological parents) and expression of genes and proteins in the lining of the intestine and colon in the development of diarrhea in patients with irritable bowel syndrome with or without bile acid malabsorption. 

The purpose of this study is to compare the effects of 5g of TU-100 three times per day (TU-100 is a botanical agent that modulates gastrointestinal nerves), and placebo on rectal sensation (sensation ratings of urgency to defecate and sensation threshold for pain) in response to rectal balloon distension by barostat in patients with IBS.

The purpose of this study is to evaluate the effects of an investigational (not yet FDA approved) medication, ROSE-010, on the movement of food through the stomach, small intestine and colon in females who have a  constipation predominant form of irritable bowel syndrome.

The purpose of this study is to measure 48 hour fecal bile acids in IBS-D adolescents and compare it to HC; measure serum C4 and FGF-19 in adolescents with IBS-D and HC and compare it to 48 hour fecal bile acid loss; measure primary bile acids concentration in 48 hour stool collection in adolescents with IBS-D and compare it to HC.

We aim to validate fasting serum C4 and primary bile acids from a single stool sample (individually or in combination) in 65 patients with diarrhea predominant irritable bowel syndrome (IBS-D), 30 healthy volunteers, and 12 patients with terminal ileal resection > 10 cm. First, we will validate the combined serum C4 and primary bile acids in patients with IBS-D without BAM, IBS-D with BAM, and healthy volunteers by comparing the individual or combined serum and stool test to documented 48 hour total fecal bile acid (current gold standard to diagnose bile acid malabsorption in the USA). Second, we will evaluate ...

This study is being done to see if Lyrica helps people with irritable bowel syndrome. Lyrica is the trade name for pregabalin, which was first approved by the FDA in June 2005 and has been available through prescription since fall 2005, and is marketed by Pfizer. Lyrica is known to have clinical efficacy treating pain disorders including irritable bowel syndrome-related conditions such as fibromyalgia.

Our overall objective with this study is firstly to provide a comprehensive assessment of intestinal permeability, mucosal barrier function using existing biomarkers and secondly to explore novel biomarkers for measuring intestinal permeability in patients with constipation predominant Irritable Bowel Syndrome (IBS-C).

This study is being done to evaluate the safety and effects of Food and Drug Administration (FDA) approved medication, Eluxadoline, on bowel function in study participants with IBS-D who do or do not have bile acid malabsorption (BAM). Eluxadoline has been approved by the FDA for people with IBS-D but it is not known whether it will work the same way in people with IBS-D who also have BAM.

Will Ranolazine improve bowel function and abdominal pain in human subjects with IBS-D?

The purpose of this study is to determine differences in microbiota composition in volunteers with and without Rome IV defined Campylobacter jejuni PI-IBS, and to determine differences in peripheral metabolites, proteins and lipids in volunteers with and without Rome IV defined Campylobacter jejuni PI-IBS.

This study comprises three sub-studies. The objective of sub-study 1 was to characterize the dose-response, efficacy, and safety of  upadacitinib compared to placebo in inducing clinical remission per Adapted Mayo score (using the Mayo Scoring System for Assessment of Ulcerative Colitis Activity, excluding Physician's Global Assessment [PGA]) in subjects with moderately-to-severely active UC in order to identify the induction dose of upadacitinib for further evaluation in Phase 3 studies including Substudy 2.

The primary objective of Substudy 2 (Phase 3 induction) is to evaluate the efficacy and safety of upadacitinib 45 mg QD compared to placebo in inducing clinical ...

This longitudinal study is being done to understand mechanisms underlying development of irritable bowel syndrome (IBS) and the role of the gut bacteria in development of symptoms. This information will be used to determine whether temporal changes in gut microbial taxonomy and metabolism are associated with changes in symptom severity in IBS, and if targeted dietary interventions, including prebiotics, can reverse or moderate these changes.

The aim of this study is to screen patients who are seen at a motility clinic for borderline personality disorder with the Mclean Screening Instrument for Borderline Personality Disorder.

The overall hypothesis of this research study is that gluten intake alters intestinal barrier function in patients with Irritable Bowel Syndrome (IBS) diarrhea who also exhibit non-celiac gluten sensitivity (NCGS).

The purpose of this study is to determine the safety profile of long-term vedolizumab IV treatment in pediatric participants with UC or CD.

To compare with a randomized trial (n=15 per treatment group), effects of colesevelam and placebo treatment, on colonic transit, bowel functions, permeability and tight junction expression in rectosigmoid mucosa of IBS-D with Bile Acid Malabsorption.

Gastrointestinal (GI) infection with Campylobacter causes inflammation in the bowel and can change bacteria in the gut. Certain individuals with Campylobacter infection are also known to develop chronic bowel problems such as Irritable Bowel Syndrome (IBS). The researchers are doing this study to understand if changes in gut bacteria and gut mucosal lining during an acute infection can help identify individuals who might be at risk for developing problems in the future.

The purpose of this study is to obtain long term safety and tolerability data of vedolizumab subcutaneous (vedolizumab SC) in participants with ulcerative colitis (UC) and Crohn's disease (CD).

The purpose of this study is to evaluate the most applicable endpoints for evaluation of the Biomerica InFoods® IBS product.

The purpose of this study is to assess patients suspected of recurrent C. difficile disease (rCDI) and using a combination of clinical and laboratory markers to determine disease versus post infectious irritable bowel syndrome (IBS) with C. difficile colonization.

The purpose of this study is to collect and annotate PEG (Phonoenterogram) data from healthy volunteers, patients with irritable bowel syndrome (IBS), patients with inflammatory bowel disease (IBD),post-surgical patients with an increased risk of developing paralytic postoperative ileus (POI), and patients with evidence of partial bowel obstruction for facilitating the technical development of the PEG-CAAe using Artificial Intelligence.

The purpose of this study is to develop a resource (bank) of biospecimens and data collected from individuals with functional gastrointestinal disorders (FGID) to facilitate discovery and development of novel microbial biomarkers of disease and response to treatment, and novel targeted therapeutic strategies for FGID.  

The purpose of this study is to assess the effectiveness in self-administered hypnotherapy protocol in decreasing the sensation of bloating, as assessed by validated patient reported outcomes, can be developed and validated using telehealth-based research, and digitally delivered.  

The purpose of this study is to evaluate abdominal pain response to BOS-589 in participants with diarrhea-predominant Irritable Bowel Syndrome (IBS-D) after 4 weeks of treatment, and to evaluate the overall safety and tolerability of BOS-589 in the treatment of IBS-D during 4 weeks of treatment, relative to placebo (PBO).

Some people develop chronic abdominal pain with diarrhea or constipation after an episode of acute bacterial gastroenteritis. These symptoms can be consistent with post-infectious irritable bowel syndrome (IBS) and can last long after the acute infection is over. The exact reason why certain individuals develop these symptoms whereas others don't is not exactly clear. The researchers are studying changes in gastrointestinal permeability (movement of contents across the lining of the intestine) and transit (movement of food through the gastrointestinal tract). The researchers are also studying if there are any genetic risk factors that are associated with development of this disorder.

The purpose of this study is to:

1. To evaluate the pharmacogenomic profile (PGx) by genotyping 22 genes, including the CYP2D6 genotype, in patients with functional GI disorders.
2. To assess the impact of PGx testing on prescriber patterns in this practice.
3. To explore the impact of PGx testing on patient outcomes after an assessment in this practice.