Randomized, Double-Blind, Controlled Study of Losartan in Children with Proteinuria

Background and objectives: No large, randomized, double-blind trials in children with proteinuria treated with angiotensin-converting enzyme inhibitors or angiotensin receptor blockers have previously been reported. Design, setting, participants, & measurements: This 12-week, double-blind, multinational study investigated the effects of losartan 0.7 to 1.4 mg/kg per day compared with placebo (normotensive stratum) or amlodipine 0.1 to 0.2 mg/kg per day up to 5 mg/d (hypertensive stratum) on proteinuria (morning-void urinary protein-creatinine ratio, baseline >= 0.3 g/g) in 306 children up to 17 years of age. Results: Twelve weeks of treatment with losartan significantly reduced proteinuria compared with amlodipine/placebo: losartan -35.8% (95% confidence interval: -27.6% to -43.10%) versus amlodipine/placebo 1.4%, (95% confidence interval: -10.3% to 14.5%)), P <= 0.001. Significance remained after adjustment for differences across treatment groups in change in BP (losartan produced incremental systolic and diastolic BP reductions versus amlodipine of 5.4 and 4.6 mmHg, respectively; and versus placebo of 3.8 and 4.0 mmHg, respectively). Proteinuria reduction was consistently observed in the normotensive (-34.4%, losartan; 2.6% placebo) and hypertensive (-41.5% losartan; 2.4% amlodipine) strata, and in all prespecified sub-groups, including age, gender, race, Tanner stage, weight, prior therapy with angiotensin-converting enzyme inhibitors or angiotensin receptor blockers, as well as among the most common etiologies of proteinuria. Adverse event incidence was low and comparable in all groups. Conclusions: Losartan significantly lowered proteinuria and was well tolerated after 12 weeks in children aged 1 to 17 years with proteinuria with or without hypertension, a population that has not previously been rigorously studied. Clin J Am Soc Nephrol 5: 417-424, 2010. doi: 10.2215/CJN.06620909