Cyclosporine C2 monitaring for frequently relapsing nephrotic syndrome in children: A randomized controlled trial

INTERVENTION: Cyclosporine C2 monitoring with higher target levels Cyclosporine C2 monitoring by lower target levels CONDITION: Frequently relapsing nephrotic syndrome in children PRIMARY OUTCOME: Relapse‐free rate INCLUSION CRITERIA: 1.Primary nephrotic syndrome (proteinuria with a urinary protein‐creatinine ratio >1.8 and hypoalbuminemia with serum albumin level <2.5 g/dL). 2.Frequently relapse or steroid independence, based on the International study of kidney disease in children. 3.Biopsy diagnoses of MCNS, MPGN or FSGS, where a renal biopsy has been performed within 12 months before eligibility. 4.Aged twelve months to 18 years. 5.Written informed consent from the patients' parents or legal guardians.