Efficacy and Safety of Obinutuzumab Versus Rituximab in Childhood Steroid Dependant and Frequent Relapsing Nephrotic Syndrome (OBIRINS)

Inclusion Criteria: Age between 3 and 18 years Steroid dependant Nephrotic Syndrome defined as: 2 or more relapses during steroids or within 2 weeks following discontinuation. 2 or more relapses including one under steroid-sparing agent (MMF, Calcineurin inhibitors, cyclophosphamide, levamisole) or within 6 months following treatment withdrawal OR Frequent Relapsing Nephrotic Syndrome defined as: 2 or more relapses within 6 months following first remission 3 or more relapses within any 12-month period Last relapse within 3 months prior to inclusion In remission, defined as 3 consecutive urinary dipsticks without proteinuria, at the time of randomization Vaccination schedule in accordance with the current recommendations in France Informed consent from parents Exclusion Criteria: Secondary cause of nephrotic syndrome (such as membranous nephropathy, IgA nephropathy, lupus nephritis) Primary or secondary steroid resistance nephrotic syndrome Prior treatment with Rituximab within 6 months Prior treatment with obinutuzumab at any time CD20+ B-cell count < 2.5% Patient with neutrophils < 1.5 G/L and/or platelets < 75 G/L GFR < 80 ml/min/1.73m2 Weight <16kg History of severe infection such as tuberculosis, hepatitis B, hepatitis C or HIV infection or LEMP History of malignancy- Uncontrolled infection (viral, bacterial and fungal) Vaccination with a live vaccine within 4 weeks prior to assignment/randomization Known hyperprolinemia Hypersensitivity to the active substance (OBI or RTX) or to proteins of murine origin, or to any of the other excipients Pregnancy or breastfeeding or ability to become pregnant and refusal to use effective contraception during the 18 months following the study treatment (only 1 infusion of obinutuzumab/Rituximab at the beginning of the study) Patient without medical insurance coverage (beneficiary or legal)