PRevention of End Stage Kidney Disease by Darbepoetin Alfa In Chronic Kidney Disease Patients With nondiabeTic Kidney Disease

Inclusion Criteria: 1. CKD patients who have not received chronic dialysis 2. eGFR 8 and more and less than 20 mL/min/1.73m2 determined twice in last 12 weeks. 3. CKD patients with renal anemia at Hb less than 10g/dL within last 8 weeks 4. CKD patients with TSAT 20% and higher or serum ferritin 100ng/mL and higher. 5. CKD patients treated with standard care 6. CKD patients provided written informed consent. Exclusion Criteria: 1. Diabetes (treated, or HbA1c 6.4% IFCC) 2. CKD patients treated with ESA other than epoetins and darbepoetin. 3. CKD patients treated with epoetin 24000 IU/4w or more. 4. CKD patients treated with darbepoetin 90μg/4w or more. 5. Uncontrolled hypertension (180/10mmHg and higher) 6. Heart failure (NYHA III and IV) 7. malignancy, hematological disorder 8. malnutrition 9. Active and continuous gastrointestinal tract bleeding 10. ANCA associated glomerulonephritis, acute infection, active SLE 11. CKD patients who will undergo dialysis or receive transplantation within 6 months 12. Myocardial infarction within last 6 months 13. Stroke or pulmonary embolism within last 12 months 14. Severe allergy 15. Pregnant women, women on lactation, or CKD patients who plant to get pregnant 16. Allergy against erythropoetin 17. Ineligible patients according to the investigator's judgment