Role of transplantation of fecal microbiota from healthy individuals to patients with Crohn's disease and its effect on achieving control of disease activity

INTERVENTION: Participants will be randomly assigned to receive either FMT or a placebo at four scheduled intervals: weeks 0, 4, 12, and 20. The placebo will consist of food‐grade color mixed in normal saline. Both FMT and placebo will be administered via colonoscopy, with the fecal slurry or placebo solution delivered into the terminal ileum or cecum. Preparation of fecal slurry: The fecal slurry for FMT will be freshly prepared on the day of each intervention from healthy, unrelated voluntary donors. These donors will undergo thorough screening to ensure the absence of transmissible diseases and other health risks. The stool will be processed to create a slurry suitable for transplantation. Assessment of disease activity and response: At each visit, disease activity and response to therapy will be assessed using the Crohn's Disease Activity Inde X(CDAI). Endoscopic findings will be recorded, with disease activity graded according to the Simple Endoscopic Score for Crohn's Disease (SES‐CD). These assessments will help monitor the clinical progression and response to treatment. Study schedule: Week 0: Initial FMT or placebo administration, baseline fecal sample collection, CDAI and SES‐CD assessments Week 4: Second FMT or placebo administration, CDAI and SES‐CD assessments Week 12: Third FMT or placebo administration, CDAI and SES‐CD assessments Week 20: Fourth FMT or placebo administration, CDAI and SES‐CD assessments Week 24: Final assessment of disease activity using CDAI and SES‐CD, fecal sample collection for microbiome analysis, and evaluation of successful engraftment Data analysis: Data collected will be analyzed to determine the efficacy of FMT in inducing clinical remission and endoscopic response in patients with Crohn's disease. The similarity of microbiota between CONDITION: Crohn's disease of both small and large intestine ; Digestive System PRIMARY OUTCOME: 1. Clinical remission defined as a CDAI score of less than 150 at 24 weeks; 2. Endoscopic response defined as a 50% reduction in the SES‐CD score from baseline at 24 weeks SECONDARY OUTCOME: 1. Gut microbiome composition assessed via fecal metagenome analysis at baseline and week 24; 2. Safety and adverse events: adverse events related to FMT will be meticulously recorded using a pre‐designed template throughout the study. The severity of these events will be graded according to the American Society of Gastrointestinal Endoscopy (ASGE) report criteria. This process will ensure comprehensive monitoring of any negative effects associated with the intervention. INCLUSION CRITERIA: 1. Patients with mild to moderate active CD, defined as CDAI 150‐449 2. Ileal, ileo‐colonic or colonic disease location 3. Inflammatory (non‐penetrating non‐stricturing disease behavior) 4. Diagnosis (endoscopic or radiographic and histological) of IBD at least 6 months prior to enrolment into the study 5. Subjects who are willing and able to comply with treatment plan, laboratory tests 6. Subjects who are willing to provide written informed consent