A phase 2b, randomised, double-blind, placebo-controlled multicentre study to evaluate the efficacy, safety and tolerability of orally administered full-spectrum microbiome therapeutic (EBX-102-02) in participants with moderate to severe irritable bowel syndrome with constipation
Irritable Bowel Syndrome - constipation predominant (IBS-C)
Trial arms: Participants will be randomly assigned in a 1:1:1 ratio to three treatment arms: 1. Active treatment arm 1: participants will receive study drug EBX-102-02 2. Active treatment arm 2: participants will receive study drug EBX-102-02 SD 3. Control group: participants will receive a ‘placebo’ treatment Neither the participants nor the study team will know who is receiving the study drug or the placebo. Study drugs: EBX-102-02 and EBX-102-02 SD are gastro-resistant hard hydroxypropyl methylcellulose (HPMC) capsules containing dried gut bacteria derived from rigorously screened human stool samples. EBX-102-02 (containing material pooled from multiple donors) and EBX-102-02 SD (derived from a single donor) are two versions of the same investigational medicinal product with similar types and numbers of gut bugs. Visual and weight-matched placebo capsules are utilised to maintain the blind. Randomisation: Participants will be randomly assigned by an interactive web-based Randomization and Trial Supply Management (RTSM) tool. Randomisation will be performed using a stratified approach according to baseline disease severity (moderate and severe), with allocation balanced across treatment arms. Dose, schedule and frequency: The study will last for up to 18 weeks, including a screening period of up to 4 weeks ahead of dosing, with participants attending a total of six visits. Updated 15/07/2026: The study will last for up to 19 weeks, including a screening period of up to 5 weeks ahead of dosing, with participants attending a total of six visits. Each dose consists of eight capsules taken in the clinic at four of these visits (at weeks 0, 1, 5, and 9 after screening). Participants will be followed up for 5 weeks after the last dose. Route of administration: oral administration.
1. Participant must be 18 to 70 years of age, inclusive, at the time of signing the informed consent 2. Participants who: 2.1. Have a clinical diagnosis of IBS-C, as confirmed by Rome IV grading criteria (including only participants with at least moderate disease intensity by using an IBS-SSS inclusion of ≥ 175 (recorded at both screening assessment and confirmed at the baseline entry), AND 2.2. Reported IBS-C symptom onset at least 6 months before Screening Date 3. Willing to discontinue all medications for bowel habit abnormalities (IBS-C, IBS-D, and IBS-M) after providing consent. 4. Report an average weekly worst abdominal pain intensity score ≥ 3.0 on a 0-10 numeric scale 5. Have fewer than three (3) complete spontaneous bowel movements (CSBMs) per week recorded in DIBSS-C during the Screening assessment 6. Willing to abstain from consuming regular ‘over-the-counter’ pre- or probiotics from pharmacies or other retailers from screening through to end of follow-up 7. No clinically significant abnormalities in vital signs (blood pressure, heart/pulse rate, respiratory rate, oral temperature) determined within 28 days before first dose of study drug 8. No clinically significant abnormalities in 12-lead electrocardiogram (ECG) determined within 28 days before first dose of study drug. 9. Participants with lactose intolerance who are on a dairy free diet or use lactase-containing products when consuming dairy may be included in the study 10. Body Mass Index within the range 17.5 to 35 kg/m2 (inclusive) 11. Contraceptive use by participants or their partners should be consistent with the requirements stipulated in the study protocol 12. Signed informed consent, which includes compliance with the requirements and restrictions listed in the ICF and in the study protocol 13. Willing and able to comply with all study requirements.
1. Diarrhoeal illness within 7 days prior to Screening based on clinical judgement 2. Infectious diarrhoea including C. difficile or diarrhoea associated with foreign travel within 12 months of screening 3. Other clinically significant chronic gastrointestinal (GI) disease, as per the opinion of the Investigator including: inflammatory bowel disease, diverticulitis (uncomplicated diverticulosis will not exclude a participant from the study), gastro-oesophageal reflux disease uncontrolled by medication, eosinophilic oesophagitis or other eosinophilic GI diseases, microscopic colitis, malabsorption syndromes e.g. coeliac disease. Further guidance and examples are provided in the study protocol. 4. Any history of malignant tumours (primary or secondary) affecting any part of the GI tract including participants with known familial colorectal cancer syndromes (e.g. Lynch) or any conditions associated with increased risk of GI cancer (e.g., familial adenomatous polyposis coli - FAP) 5. History of colectomy/ileostomy at any time 6. History of colonic perforation or fistula at any time 7. History of any malignancy within the 5 years prior to screening, excluding non-melanoma skin cancers 8. Participants with clinically significant dysphagia, or inability to ingest capsules (e.g. severe nausea, vomiting, delayed gastric emptying) as per the opinion of the Investigator, or history of ‘choking’ on capsules 9. Any significant abdominal surgical intervention with the following exceptions: appendectomy, hernia repair, laparoscopic cholecystectomy, and gynaecological and urological procedures including hysteroscopy and cystoscopy. None of these noted surgical exceptions are allowed within 12 months prior to Screening. No upper endoscopy or colonoscopy within 2 months prior to Screening. 10. History of human immunodeficiency virus (HIV), hepatitis B virus (HBV) or hepatitis C virus (HCV) infection, regardless of current viral status and test results 11. Any autoimmune or oncologic