Beneficial effect of aliskiren combined with olmesartan in reducing urinary protein excretion in patients with chronic kidney disease

Blockade of the renin-angiotensin-aldosterone system is a therapeutic mainstay in patients with chronic kidney disease (CKD). However, the renoprotective effect of the novel direct renin inhibitor aliskiren is unknown. We performed a prospective study in 10 CKD patients. All 10 patients with persistent proteinuria (urinary protein-to-creatinin ratio 0.3-3.5 g/g), despite good blood pressure control (< 130/80 mmHg) with olmesartan, were started on 150 mg/day aliskiren. Clinical parameters were examined before and after 4, 8, 12, and 16 weeks of treatment. Urinary protein-to-creatinine ratio significantly decreased by about 40% at 16 weeks from baseline (P = 0.0002), although estimated glomerular filtration rate and blood pressure did not change throughout the study period. Plasma renin activity also decreased significantly from baseline (P = 0.019), although plasma aldosterone concentration did not change. Aliskiren combined with olmesartan reduces proteinuria in CKD patients.