Evaluation of the comparative efficacy and safety of obinutuzumab and other follow-up strategies after rituximab failure in refractory nephrotic syndrome.

BACKGROUND

Refractory nephrotic syndrome (RNS) in children remains difficult to manage, particularly in patients who fail to maintain sustained remission after rituximab (RTX). Optimal follow-up treatment strategies after RTX failure remain unclear. This study aimed to evaluate the efficacy of different follow-up treatment strategies after RTX failure.

METHODS

This retrospective study included children with RNS who failed to maintain sustained remission after a single course of RTX. According to subsequent treatment, patients were divided into three groups: anti-CD20-free maintenance therapy (ACF), RTX retreatment (RTX-R), and obinutuzumab treatment (OBZ). Patients in the ACF group received corticosteroids and/or other immunosuppressants without additional anti-CD20 biologics, whereas those in the RTX-R and OBZ groups received RTX or OBZ therapy respectively.

RESULTS

Twenty-eight children were included: 10 in the ACF group, 8 in the RTX-R group, and 10 in the OBZ group. At 6 months, the OBZ group demonstrated significantly higher relapse-free survival compared to both the RTX-R group (100% vs. 37.5%, P < 0.01) and the ACF group (100% vs. 30%, P < 0.01), with no difference between the RTX and ACF groups. At 52 weeks, relapse-free survival remained highest in the OBZ group (80.0%), compared with 25.0% in the RTX-R group and 30.0% in the ACF group. OBZ induced sustained peripheral B-cell depletion, with B cells remaining undetectable throughout the scheduled 6-month follow-up. No serious adverse effects were observed in three groups.

CONCLUSION

Obinutuzumab may be an effective and safe follow-up option for children with RNS who fail to maintain sustained remission after RTX.