Efficacy and safety of calcitriol therapy for reduction of proteinuria in children with chronic kidney disease: an open-label randomized controlled trial

Abstract

Purpose: Reducing proteinuria in children with chronic kidney disease (CKD) has been shown to slow the progression of kidney damage. Hence, we examined the efficacy of a combination of calcitriol and enalapril as compared to enalapril alone in reducing proteinuria in children with CKD.

Methods: Children aged 3 to 18 years with CKD and proteinuria > 250 mg/m²/day were randomized to receive enalapril (0.6 mg/kg/daily) with or without calcitriol (0.25 µg twice weekly) for 6 months. Children with estimated GFR (eGFR) < 30 ml/min/1.73 m², serum calcium > 10.5 mg/dl, and phosphate > 5.5 mg/dl were excluded. A primary outcome was a mean difference in the change in proteinuria at 6 months compared to baseline. Secondary outcomes included changes in PTH and eGFR.

Results: Of 212 screened children with CKD and proteinuria, 72 (56 boys, mean age 11.2 ± 3.4 yr) were randomized. Baseline characteristics were similar in both groups. Proteinuria decreased from the baseline to the end of therapy by median 1.05 (IQR: 0.04 to 1.87) g/day with the combination therapy as compared to median 0.49 (IQR: 0.03 to 1.33) g/day in enalapril group (P = 0.54). The percentage reduction in proteinuria was 60.4% with the combination therapy and 50.1% with enalapril therapy (P = 0.48). Three patients developed hyperphosphatemia in enalapril therapy; hypercalcemia and hyperkalemia were not observed.

Conclusion: In children with CKD, the combination of calcitriol and enalapril did not result in significant reduction in proteinuria than enalapril alone. Combination therapy was tolerated well. Further studies with a larger sample size and a longer duration of follow-up studies are needed. Trial registration https://ctri.nic.in CTRI/2011/10/002086. Registered in October 21, 2011.

Keywords: Chronic kidney disease; Enalapril; Kidney failure; Proteinuria; Vitamin D.