A Study to Evaluate the Efficacy and Safety of Obinutuzumab Versus MMF in Participants With Childhood Onset Idiopathic Nephrotic Syndrome

Inclusion Criteria: * Diagnosis of frequently relapsing nephrotic syndrome (FRNS) or steroid dependent nephrotic syndrome (SDNS) before the age of 18 years * Must be in complete remission defined by the absence of edema, UPCR \<= 0.2 g/g at screening and have three consecutive daily urine dipstick readings of trace or negative for protein within the week prior to randomization * Must have had at least one relapse in the 6 months prior to screening, after discontinuation of or while receiving oral corticosteroids and/or immunosuppressive therapy to prevent relapses * Participants having received cyclophosphamide in the 6 months prior to randomization must have experienced at least 1 relapse subsequent to cyclophosphamide discontinuation * Estimated glomerular filtration rate (eGFR) within normal range for age * For females of childbearing potential: participants who agree to remain abstinent (refrain from heterosexual intercourse) or use highly effective contraception, during the treatment period and for 18 months after the final dose of obinutuzumab and for 6 weeks after the final dose of MMF * For males: participants who agree to remain abstinent (refrain from heterosexual intercourse) or use contraceptive methods, and agree to refrain from donating sperm during the treatment period and for 90 days after the final dose of MMF Exclusion Criteria: * Secondary nephrotic syndrome * History of steroid resistant nephrotic syndrome * History of genetic defects known to directly …