The purpose of this study is to evaluate the effect of aliskiren, a novel direct rennin inhibitor, on renal function and progress of renal disease in hypertensive patients with IgA nephropathy.

Inclusion Criteria:

• IgA nephropathy confirmed by renal biopsy
• Hypertension (<= 125/75 mmHg)

Exclusion Criteria:

• Patients who have been treated with angiotensin type 1 receptor blocker or angiotensin-converting enzyme inhibitor within 4 weeks
• Severe hypertension (<= 180/110 mmHg) or secondary hypertension
• Patients with history of allergy or adverse effect for aliskiren
• Renal dysfunction (estimated Glomerular Filtration Rate < 60 mL/min/1.73m2)
• Pregnancy
• Patient treated with cyclosporine
• Hyperkalemia (serum potassium >= 5.6 mmol/L)
• Autoimmune disease including systemic lupus erythematosus
• Patients inadequate for the study