Coated Aldehyde Oxystarch for Protein-Bound Uremic Toxin Reduction in End-Stage Renal Disease

Inclusion Criteria: * Age ≥ 18 years, no restriction on sex or ethnicity. * Receiving maintenance dialysis for at least 3 months, with dialysis regimen remaining unchanged during the trial period. * If taking other medications that do not interfere with gut microbiota prior to enrollment, they must have been stable for at least 1 month and the regimen must remain unchanged during the trial. * Ability to understand and voluntarily sign the informed consent form. Exclusion Criteria: * Known allergy to Coated Aldehyde Oxystarch. * History of or planned kidney transplantation within 6 months, or change in dialysis regimen. * Use of medications or supplements that may affect gut microbiota (e.g., antibiotics, probiotics, prebiotics, laxatives) within the past 3 months. * Diagnosis of serious gastrointestinal diseases, including gastrointestinal bleeding, colitis, inflammatory bowel disease, irritable bowel syndrome, history of intestinal obstruction, history of gastrectomy or duodenectomy. * History of cardiovascular or cerebrovascular events within 3 months prior to screening, including hospitalization for stroke, myocardial infarction, unstable angina, congestive heart failure; severe valvular stenosis, uncontrolled atrial fibrillation or arrhythmia; QTc interval \>500 ms on repeated ECG. * Concurrent severe primary diseases of cardiovascular, cerebrovascular, hepatic, hematopoietic systems, or other known life-threatening diseases (e.g., malignancy, AIDS), or patients with mental or legal disabilities. * Investigator judges life expectancy ≤6 months. * Inability to maintain stable dietary habits during the study period. * Inability to maintain original dialysis regimen during the study period. * Use of Chinese patent medicines for kidney disease (e.g., Shenkang Injection, Haikun Shenxi Capsule, Shenshuaining, Tripterygium preparations, Niaoduqing Granules) within 1 month prior to enrollment. * Participation in another clinical trial within the past 1 month. * Intellectual disability, psychiatric disorders, or suspected/confirmed history of alcohol or drug abuse that may affect compliance. * Any other condition that, in the investigator's judgment, makes the patient unsuitable for participation in this study.