Singapore - Malaysia - Shanghai Kidney Trial - Nephrotic Syndrome (SMART-NS): dulepivoumab for maintenance treatment of steroid-dependent and frequently relapsing nephrotic syndrome

INTERVENTION: Placebo Group:Placebo;Experimental Group:Dupilumab; CONDITION: Nephrotic Syndrome in Children PRIMARY OUTCOME: Time to relapse; SECONDARY OUTCOME: Time‐averaged Albusti Xquantitation of proteinuria during study period;Percentage reduction in prednisolone dose at the end of study compared to baseline;Minimum dose of prednisolone at the end of study;Change in health‐related quality of life at the end of study compared to baseline;Number of participants with adverse events; INCLUSION CRITERIA: 1.Age between 2 years old and 18 years old at the point of recruitment with idiopathic nephrotic syndrome with disease onset between 1‐18 years old; 2.Steroid‐dependent disease or frequently relapsing disease prior to commencement of maintenance immunosuppression; 3.On oral prednisolone +/‐ mycophenolate or levamisole only as maintenance therapy for 6 months or more, and with inadequate disease control or steroid toxicity on therapy; 4.Nephrotic relapse or partial relapse (clinical or biochemical) within the last 1 year either unprovoked or during prednisolone wean, and which responded to increase in steroids; 5.In complete remission at the time of recruitment; 6.Competent with, and compliant to, daily urine protein monitoring with Albustix;