Beginning of Effective and Safe Treatment in Immunoglobulin A-1 Nephropathy-1

Inclusion Criteria: 1. Biopsy-proven IgAN: dominant or co-dominant deposits of mesangial IgA in immunofluorescence stain 2. Age \>= 19 years 3. Random urine protein-to-creatinine ratio 0.3 g/g creatinine to 1.0 g/g creatinine at visit 1 4. Estimated glomerular filtration rate \>= 60 mL/min/1.73m2 at visit 1 5. People who voluntarily agreed to participate 6. People who are compliant Exclusion Criteria: 1. Prevalent Hypertension: systolic blood pressure \>=140 mmHg and \>=90 mmHg, previous physician diagnosis of hypertension, or taking anti-hypertensive drugs 2. Prevalent Diabetes: fasting glucose \>= 126 mg/dL, HbA1c \>= 6.5%, taking insulin or anti-diabetic drugs, or previous physician diagnosis of diabetes 3. Previous immunosuppressive drugs use to treat IgAN 4. Secondary IgAN 5. Renin-angiotensin-aldosterone inhibitors (RASI) dependent patients (congestive heart failure, ischemic heart disease, and others) 6. hypersensitivity to RASI 7. Other chronic diseases: malignancy within 5 years, significant liver and gastrointestinal disease and other autoimmune disease 8. Pregnancy 9. symptomatic orthostatic hypotension 10. People who already participated in other interventional studies or taking interventional drugs within 3 month of screening visit 11. Inappropriate people ascertained by investigator