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

A Randomized, Double Blinded, Placebo-controlled, Multicenter, Phase III Study to Evaluate the Efficacy and Safety of Losartan in Early Immunoglobulin A Nephropathy (IgAN) Patients

Immunoglobulin A nephropathy (IgAN) is the most common glomerulonephritis worldwide. IgAN is progressive, particularly when patients have a significant proteinuria (proteinuria >1g/g creatinine), impaired kidney function, or elevated blood pressure. In 10 years, nearly 20-40% of these IgAN patients progress to end-stage renal disease (ESRD). Early IgAN is tentatively defined when proteinuria is insignificant and kidney function and blood pressure are normal. Patients with early IgAN rarely progress to ESRD. However, 30-40% of patients with early IgAN ultimately developed a significant proteinuria and hypertension in 10 years. Therefore, earlier intervention may be needed if it can prevent the development of a significant proteinuria and hypertension. Since angiotensin ll receptor blocker (ARB) is drug of choice in reducing proteinuria and controlling blood pressure, the investigators hypothesized that early introduction of ARB may be beneficial in preventing the significant proteinuria development in early IgAN patients. To prove the hypothesis, the investigators plan the current interventional study.

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