Rituximab for troublesome cases of childhood nephrotic syndrome

The Efficacy and Safety of Rituximab for Childhood Steroid-Dependent Nephrotic Syndrome: A Systematic Review and Meta-Analysis

Objectives: Rituximab (RTX), a possible alternative treatment option, is recognized as a new therapeutic hope for the treatment of steroid-dependent nephrotic syndrome (SDNS) in children. However, the efficacy and safety of RTX in the treatment of childhood SDNS are still controversial. The objective of this study was to evaluate the efficacy and safety of RTX treatment in children with SDNS. Study Design: Six randomized controlled trials (RCTs) and one retrospective comparative control study data from studies, performed before January 2021 were collected, from PubMed, Cochrane Library, Embase, and Web of Science. The studies evaluating the efficacy and safety of RTX in childhood SDNS were included. Results: Six RCTs and one retrospective comparative control study were included in our analysis. Compared with the control group, the RTX treatment group achieved a higher complete remission rate (OR = 5.21; 95% CI, 3.18-8.54; p < 0.00001), and we found significant differences between the two groups on serum albumin level (MD = 0.88; 95% CI, 0.43-1.33; p = 0.0001) and estimated glomerular filtration rate (MD = 6.43; 95% CI, 2.68-10.19; p = 0.0008). However, RTX treatment did not significantly lower serum creatinine levels nor did it significantly reduce the occurrence of proteinuria. In addition, we found no advantages with RTX on treatment safety. Conclusions: RTX has shown satisfactory characteristics in terms of efficacy and may be a promising treatment method for SDNS in children. However, the long-term effects have not been fully evaluated and should be further studied through randomized clinical trials.

Long-term repeated rituximab treatment for childhood steroid-dependent nephrotic syndrome

BACKGROUND

Rituximab (RTX) can be used as a rescue therapy for steroid-dependent nephrotic syndrome (SDNS). However, the efficacy and safety of long-term, repeated use of RTX are not established. This study was conducted to assess the efficacy and safety of long-term, repeated RTX treatment in children.

METHODS

Eighteen consecutive child patients with SDNS who were treated with three or more cycles of RTX for one year or longer were recruited, and their medical records were retrospectively reviewed.

RESULTS

The patients were followed for 4.7 ± 1.9 years and received 5.2 ± 2.3 cycles of RTX over 2.8 ± 1.1 years. Approximately 70% of the additional RTX cycles were administered due to recovery of B-cells without relapse. The relapse rate decreased from 3.4 ± 2.0 per year initially to 0.4 ± 0.8 per year at the third year after RTX treatment. Approximately 10% of the RTX infusions were accompanied by mild infusion reactions. Eight patients showed sustained remission without any oral medication after the last cycle of RTX, while 10 patients had one or more episodes of relapse after the last cycle of RTX. The relapse rate in the latter group decreased from 2.8 ± 1.5 per year before RTX treatment to 1.3 ± 0.8 per year after cessation of RTX treatment. No significant differences in clinical parameters were found between the two groups.

CONCLUSION

This retrospective study showed that pre-emptive and long-term, repeated RTX treatment is relatively effective and safe in children with SDNS. However, well-designed prospective studies are needed to confirm these findings.

Ofatumumab in two pediatric nephrotic syndrome patients allergic to rituximab

BACKGROUND

Rituximab, a chimeric anti-CD20 monoclonal antibody, is an effective treatment in steroid-dependent nephrotic syndrome (SDNS). However, some patients develop adverse reactions.

CASE-DIAGNOSIS/TREATMENT

Patient 1, a 14-year-old boy with SDNS since the age of 2, was treated with oral prednisone, cyclosporine A (CsA) and mycophenolate mofetil. A first infusion of rituximab at age 12 years was well tolerated, but this was followed by a prolonged relapse unresponsive to oral prednisone, mycophenolate mofetil and CsA. A second rituximab infusion was attempted, but treatment was interrupted due to severe dyspnea. Treatment with a humanized anti-CD20 monoclonal antibody, ofatumumab, was then attempted. The patient experienced a mild allergic reaction and maintained remission despite interruption of all treatment at >12 months of follow-up. Patient 2, a 3-year-old boy who presented at 18 months with nephrotic syndrome initially resistant to treatment with oral prednisone, was given with three intravenous boluses of methylprednisolone followed by CsA and achieved remission. Upon steroid discontinuation, the NS relapsed. Prednisone was restarted and treatment with a single dose of rituximab was never completed due to a severe allergic reaction. Ofatumumab infusion was uneventful, and he maintained remission during the follow-up period (>12 months) despite interruption of prednisone therapy. B cells reappeared at 7 months in both patients.

CONCLUSIONS

Ofatumumab may be a therapeutic option in severe forms of NS with allergy to rituximab.