Rituximab in childhood steroid-sensitive nephrotic syndrome: are multiple subsequent courses safe and effective?

Long-Term Efficacy and Safety of Repeated Rituximab to Maintain Remission in Idiopathic Childhood Nephrotic Syndrome: An International Study

BACKGROUND

Long-term outcomes after multiple courses of rituximab among children with frequently relapsing, steroid-dependent nephrotic syndrome (FRSDNS) are unknown.

METHODS

A retrospective cohort study at 16 pediatric nephrology centers from ten countries in Asia, Europe, and North America included children with FRSDNS who received two or more courses of rituximab. Primary outcomes were relapse-free survival and adverse events.

RESULTS

A total of 346 children (age, 9.8 years; IQR, 6.6-13.5 years; 73% boys) received 1149 courses of rituximab. A total of 145, 83, 50, 28, 22, and 18 children received two, three, four, five, six, and seven or more courses, respectively. Median (IQR) follow-up was 5.9 (4.3-7.7) years. Relapse-free survival differed by treatment courses (clustered log-rank test P<0.001). Compared with the first course (10.0 months; 95% CI, 9.0 to 10.7 months), relapse-free period and relapse risk progressively improved after subsequent courses (12.0-16.0 months; HRadj, 0.03-0.13; 95% CI, 0.01 to 0.18; P<0.001). The duration of B-cell depletion remained similar with repeated treatments (6.1 months; 95% CI, 6.0 to 6.3 months). Adverse events were mostly mild; the most common adverse events were hypogammaglobulinemia (50.9%), infection (4.5%), and neutropenia (3.7%). Side effects did not increase with more treatment courses nor a higher cumulative dose. Only 78 of the 353 episodes of hypogammaglobulinemia were clinically significant. Younger age at presentation (2.8 versus 3.3 years; P=0.05), age at first rituximab treatment (8.0 versus 10.0 years; P=0.01), and history of steroid resistance (28% versus 18%; P=0.01) were associated with significant hypogammaglobulinemia. All 53 infective episodes resolved, except for one patient with hepatitis B infection and another with EBV infection. There were 42 episodes of neutropenia, associated with history of steroid resistance (30% versus 20%; P=0.04). Upon last follow-up, 332 children (96%) had normal kidney function.

CONCLUSIONS

Children receiving repeated courses of rituximab for FRSDNS experience an improving clinical response. Side effects appear acceptable, but significant complications can occur. These findings support repeated rituximab use in FRSDNS.

Comparison of rituximab, cyclophosphamide, and tacrolimus as first steroid-sparing agents for complicated relapsing/steroid-dependent nephrotic syndrome in children: an evaluation of the health-related quality of life

INTRODUCTION

Frequently-relapsing/steroid-dependent nephrotic syndrome (FRSDNS) leads to steroid toxicity impairing quality of life (QOL), thus prompting the use of steroid-sparing drugs.

METHODS

51 FRSDNS children not previously treated with steroid-sparing agents were randomized to receive rituximab, cyclophosphamide, or tacrolimus. Clinical findings and QOL were evaluated before and after treatment.

RESULTS

The mean relapse rate in all groups declined six months after treatment, however, 1-year relapse-free survival rate, number of relapses, and cumulative prednisolone dosage were lower with rituximab than with tacrolimus and cyclophosphamide. Cyclophosphamide group had twice frequency of infections compared to the other groups. At 1 year after treatment, total scores showed greater improvement with rituximab.

CONCLUSIONS

As first-line steroid-sparing agent, rituximab is more effective and safer than cyclophosphamide and tacrolimus in FRSDNS, and improve QOL.