Obinutuzumab as a viable therapeutic strategy in rituximab-refractory childhood frequently relapsing, steroid-dependent nephrotic syndrome that relapsed during B-cell depletion.

A subgroup of children with frequently-relapsing, steroid-dependent nephrotic syndrome relapse during B-cell depletion after rituximab. A 15-year-old boy with focal segmental glomerulosclerosis became rituximab-refractory after 5 courses of treatments, with a relapse-free period shortened to 1 month. Circulating total and memory B-cells were undetectable at the time of relapse. A single infusion of obinutuzumab sustained relapse-free remission up to the last follow-up at 18 months. There was persistent hypogammaglobulinemia but no infection was observed. Obinutuzumab may be a viable option for attaining long-term remission with reasonable side effect profiles in patients who relapse during B-cell depletion after rituximab.