Observational Study to Evaluate the Safety and Efficacy of Kremezin IDT/Fine Gran in Progressive Chronic Kidney Disease Patients.

This is a multicenter, prospective, observational study to evaluate the effectiveness and safety of Kremezin immediate-release tablets or Kremezin fine granules in adults diagnosed with advanced chronic renal failure. During routine clinical visits, the investigator will determine whether Kremezin treatment is appropriate. The investigator will prescribe the selected formulation in accordance with the product labeling and routine clinical practice. The treatment decision must be made before the participant provides consent to participate in the study and without any study-related intervention. Adults will receive Kremezin immediate-release tablets or fine granules at the approved dosage-2 g three times daily (4 tablets per dose or 1 sachet per dose, respectively)-for the treatment period determined in routine care, with study data collected through Week 48. Scr and eGFR will be recorded at baseline, Week 24 (±3 weeks), and Week 48 (±4 weeks). At Weeks 24 and 48, the investigator will also assess overall effectiveness and treatment satisfaction and collect safety information. Blood pressure and laboratory results will be collected when available. The study will not require additional treatment or visits beyond routine clinical care.