Inclusion Criteria:  Age ≥ 18 years at screening Stable CKD stage 5 not yet on dialysis with residual kidney function 5-10 ml/min/1.73m2 by CKD-EPI equation Urine output ≥ 800 ml/day Willing to participate in the study and can provide inform consent  Exclusion Criteria:  Rapid glomerular filtration rate (GFR) progression defined as a decline of eGFR >10 ml/min/1.73m2 by CKD-EPI equation in the prior 6 months before enrollment Presence of wasting diseases, cancer cachexia, tuberculosis, AIDS wasting syndrome Other active infection/inflammation determined by CRP >10 mg/L Severe gastrointestinal problem: persistent nausea/vomiting, dysphagia, chronic diarrhea, severe malabsorption Conditions at baseline requiring withdrawal from the study including severe protein energy wasting by SGA and MIS score, prior kidney transplantation with immunosuppressive agents or other serious medical conditions. Pregnancy Uncontrolled hypercalcemia (persistent serum Ca ≥10.5 mg/dl) BMI ≥ 35 kg/m2 Hypersensitivity to the active substances or to any of the excipients of Ketosteril Disturbed amino acid metabolism