Efficacy and Safety of DT01 Tablets in Patients With Irritable Bowel Syndrome With Diarrhea

Inclusion Criteria: Patients aged 18 years or older. Has a diagnosis of IBS-D (Irritable Bowel Syndrome with Diarrhea) and meets the Rome IV Criteria Additional criterion: more than 3 bowel movements per day at least 25% of the time in the last 3 months. For patients older than 50 years OR patients with a positive family history of colorectal cancer: Normal results from colonoscopy/flexible sigmoidoscopy performed within the last 2 years. For patients aged 65 years or older: Absence of ischaemic colitis, microscopy colitis or any other organic gastrointestinal disease as evidenced by the results of a colonoscopy/flexible sigmoidoscopy with biopsy performed within 12 months. Mentally competent, able to give written informed consent, and compliant to undergo all visits and procedures. Unrestricted access to a touch-tone telephone. Willingness to refrain from using loperamide within 3 days prior to run-in visit and during the run-in period. For women of childbearing potential: Use of a highly effective contraceptive method with a failure rate <1% per year throughout the entire study period. Additional criteria at randomisation: During both weeks of the run-in period: A weekly average of worst abdominal pain in the past 24 hours with a score of ≥ 3.0 according to the Visual Analogue Scale (VAS). At least one bowel movement on each day. A weekly average of at least 3 bowel movements per day. At least one stool with a consistency of Type 6 or Type 7 according to the Bristol Stool Scale (BSS) on at least 2 days per week. Less than 2 bowel movements with a consistency of Type 1 or Type 2 according to the BSS per week. Adequate compliance with the diary recording procedure defined as at least ≥80% of the nominal daily data entry. Exclusion Criteria: Diagnosis of IBS with a subtype of constipation, mixed IBS, or un-subtyped IBS. History of organic GI abnormalities, inflammatory bowel diseases, complicated diverticulosis, ischaemic colitis, microscopic colitis. History of pancreatitis, active biliary duct disease, cholecystitis or symptomatic gallbladder stone disease in the previous 6 months. History of gluten enteropathy or lactose intolerance. Hypersensitivity to the active substances or to any of the excipients of study drug or placebo. History of major cardiovascular events in the previous 6 months. History of human immunodeficiency virus infection. Uncontrolled hypertension, insulin-dependent diabetes mellitus or abnormal thyroid function. Evidence of clinically significant hepatic disease, severe renal insufficiency or anemia. Use of prohibited concurrent medication within the previous month such as antibiotics, antimuscarinic drugs, drugs enhancing GI motility and analgesics. Pregnancy or breastfeeding. Inability to understand or collaborate throughout the study. Participation in other clinical studies in the previous 4 weeks or concomitant enrollment in a clinical study. Any condition that would compromise the well-being of the patient.