Comparison of efficacy of single-dose and double-dose rituximab in the treatment of refractory nephrotic syndrome in children: a retrospective study.

BACKGROUND

The objective was to compare the efficacy of single-dose versus double-dose rituximab (RTX) regimens in children with frequently relapsing/steroid-dependent nephrotic syndrome (FRNS/SDNS).

METHODS

This retrospective study analyzed 53 pediatric FRNS/SDNS patients treated at Guangzhou First People's Hospital from January 2020 to November 2024. Patients received either single-dose (n = 36, one RTX infusion at month 0) or double-dose (n = 17, two infusions at 0 and 3 months) RTX (375 mg/m2, maximum 500 mg/dose). The RTX dosing regimen was determined based on disease severity, socioeconomic factors, and physicians' medication preferences, rather than randomization. Some patients were receiving baseline therapy with prednisone, mycophenolate mofetil, and tacrolimus. Both groups underwent steroid tapering and were followed up for at least 6 months, with 45 patients completing 12-month follow-up. Primary endpoints were relapse frequency and cumulative prednisone usage.

RESULTS

At the 6-month and 12-month follow-ups, there were no differences in relapse rates between the single-dose and double-dose groups (31% (11/36) vs. 47% (8/17) at 6 months; 36% (13/36) vs. 53% (9/17) at 12 months). Furthermore, at the 12-month follow-up, no differences were observed between the single-dose and double-dose groups in the annual relapse frequency (0.7 ± 1.1 vs. 1.0 ± 1.2 times/year) or the cumulative prednisone usage (0.21 ± 0.12 vs. 0.22 ± 0.14 mg/(kg·d)). Kaplan-Meier analysis revealed no difference in relapse-free survival between groups (log-rank test, χ2 = 2.561, P = 0.110). At 6 months, 19% (7/36) of single-dose and 24% (4/17) of double-dose patients were CD19 +B cell depleted (< 1%). No major adverse events were seen in either group.

CONCLUSION

Single-dose and double-dose RTX regimens demonstrate comparable efficacy in maintaining remission in pediatric FRNS/SDNS patients over 12 months. The extended-interval double-dose regimen provides no significant clinical advantage, suggesting that a single-dose strategy may be sufficient while reducing treatment costs.