Specimen and Data Collection for a Novel Biomarker Combination for the Differential Diagnosis of Inflammatory Bowel Disease and Irritable Bowel Syndrome. (COMBI)

Specimen and Data Collection for the COMBI Study: A Multi-center, Multi-national Clinical Evaluation of LIAISON® Calprotectin HD, a Novel Biomarker Combination for the Differential Diagnosis of Inflammatory Bowel Disease and Irritable Bowel Syndrome. COMBI: Combination of Markers for Bowel (IBD-IBS) Investigation

This study will evaluate how well the a new stool test can distinguish inflammatory bowel disease (IBD) from non-IBD conditions compared with standard calprotectin testing and colonoscopy findings. Participants will undergo only routine clinical care, including colonoscopy, and will provide a stool sample for testing. The study will also examine how test results relate to endoscopic, histologic, and ultrasound measures of disease activity. Findings may help determine whether the new test could reduce unnecessary colonoscopies and support future regulatory submissions.

Study Overview

• Status: Enrolling by invitation
• Conditions: Gastrointestinal Symptoms; IBS (Irritable Bowel Syndrome); IBD (Inflammatory Bowel Disease)

Detailed Description

This study will evaluate the performance of a new stool-based laboratory test, which is designed to help identify inflammatory bowel disease (IBD). The study will compare this new test to standard fecal calprotectin testing. The goal is to determine how accurately the new assay can distinguish IBD from non-IBD conditions when compared with clinical diagnosis based on colonoscopy findings.

Participants will be individuals undergoing routine medical evaluation for symptoms suggestive of IBD. All medical care-including colonoscopy and biopsy collection (if applicable)-will follow standard clinical practice, and no additional procedures will be performed. Each participant will provide a stool sample for testing with the investigational device.

The study will also explore how the new test relates to endoscopic disease severity, microscopic inflammation in ulcerative colitis, and intestinal ultrasound findings. In addition, the study will estimate whether use of the new test could help reduce unnecessary colonoscopies.

This is a prospective, observational, multi-center study enrolling both pediatric and adult participants in the United States and internationally. Results from this study will support regulatory submissions in the United States and Europe.

• Study Type: Observational
• Enrollment (Estimated): 300

Contacts and Locations

Study Locations

• Italy
  • Michigan
    • Milan, Michigan, Italy, 20132
      • San Rafaelle Hospital
• United States
  • Minnesota
    • Minneapolis, Minnesota, United States, 55455
      • University of MN

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

Subjects without a diagnosis or signs/symptoms of IBD, IBS, or other chronic gastrointestinal disorders will be enrolled exclusively at selected sites.

Description

Inclusion Criteria:

• Able and willing to provide written informed consent, either personally or through a legally authorized representative
• Capable of understanding and complying with the study's stool specimen collection procedures
• For subjects under 18 years of age, enrollment will occur in accordance with applicable US IRB regulations, including informed consent from a parent or guardian and assent from the subject when appropriate (e.g., ages 14-17 years)

Exclusion Criteria:

• History of IBD, IBS, or other chronic GI disorders

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
Healthy (normal); Subjects without history or signs and symptoms of IBS, IBD, or other chronic GI disorders
Diseased Cohort; Subjects under clinical evaluation for suspected IBD exhibiting persistent lower GI symptoms and undergoing endoscopic evaluation.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Diagnostic Performance	The candidate assay will be compared to standard FC testing in differentiating IBD from non-IBD cases against a predicate (IVDR comparator) device and using the clinical SOC, specifically endoscopic classification as the reference standard.	1 year

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Correlation with Endoscopic Disease	Evaluate the relationship between device and endoscopic disease activity, defined as: A Simple Endoscopic Score for Crohn's disease (SES-CD) > 2; A Mayo Endoscopic Score (MES) > 1 for ulcerative colitis (UC)	1 year
Correlation with Histological Inflammation in Ulcerative Colitis	Assess the association between candidate device and histological inflammation in UC, defined by a Nancy Histological Index > 1.	1 year
Correlation with Intestinal Ultrasound Findings	Investigate the correlation between candidate device and intestinal ultrasound (IUS) activity, defined as: Milan Ultrasound Criteria (MUC) > 6.2 in UC; Bowel Ultrasound Susceptibility Score (BUSS) > 3.52 in Crohn's disease (CD)	1 year
Potential Reduction in Unnecessary Colonoscopies	Estimate the number of colonoscopies that could potentially be avoided by using candidate device in place of standard fecal calprotectin (FC) testing. This analysis will include quantification of reduced procedures and evaluation of associated direct and indirect healthcare costs.	1 year

Collaborators and Investigators

• Sponsor: DiaSorin Inc.

Study record dates

Study Major Dates

• Study Start (Actual): May 7, 2025
• Primary Completion (Estimated): August 1, 2026
• Study Completion (Estimated): September 1, 2026

Study Registration Dates

• First Submitted: March 10, 2026
• First Submitted That Met QC Criteria: March 10, 2026
• First Posted (Actual): March 13, 2026

Study Record Updates

• Last Update Posted (Actual): March 13, 2026
• Last Update Submitted That Met QC Criteria: March 10, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: Irritable Bowel Syndrome; IBS; Ulcerative Colitis; Inflammatory Bowel Disease; IBD; GI; Calprotectin
• Additional Relevant MeSH Terms: Intestinal Diseases; Digestive System Diseases; Gastrointestinal Diseases; Colonic Diseases; Gastroenteritis; Colonic Diseases, Functional; Colitis; Irritable Bowel Syndrome; Colitis, Ulcerative; Inflammatory Bowel Diseases
• Other Study ID Numbers: 006634

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: IPD will not be shared but a submission will be provided to FDA

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No