Comparison Of Efficacy Of Rituximab And Cyclophosphamide In The Treatment Of Frequently Relapsing And Steroid-dependent Nephrotic Syndrome In Children

Objective:To compare the clinical efficacy?side effects and costs of rituximab(RTX)and cyclophosphamide(CTX)in the treatment of frequently relapsing nephrotic syndrome and steroid-dependent nephrotic syndrome(FRNS and SDNS)in children.Methods:We retrospectively analyse the 43 chiildren with FRNS/SDNS treated with RTX or CTX in Children's Hospital of Chongqing Medical University from January 2015 to December 2019.In the RTX group(n=17),rituximab was given 375 mg/m~2.The CTX group(n=26)received 8 to 12 mg/kg of CTX intravenously,once every 2 to 4weeks,6 to 8 times in all.The cumulative dose is less than168mg/kg.Glucocorticoid was gradually reduced.The follow-up period is at least 6 months.The frequency of relapse,the steroid dose and treatment costs of the two groups were compared,and the adverse reactions were recorded.Survival curves were estimated by Kaplan-Meier method.Result:1.At 1 year followed-up,The frequency of relapse in group CTX decreased from 3.0(2.0,4.0)times per year to 0.0(0.0,1.0)times per year(P=0.000),the steroid dose decreased from 0.79(0.56,1.09)(mg/kg/d)to0.24(0.16,0.51)(mg/kg/d)(P=0.000).In the group RTX,the frequency of relapse decreased from 3.0(2.0,3.0)times per year to 0.0(0.0,1.0)times per year(P=0.001),the steroid dose decreased from 0.52(0.37,0.99)(mg/kg/d)to0.10(0.06,0.15)(mg/kg/d)(P=0.001).2.Both the steroid dose of 6months and 12 months after treatment in group RTX were lower than the group CTX(P<0.05).There was no statistically significant difference between the relapse frequency of the RTX group and the CTX group(P=0.302).3.The median time to first relapse was 10.0 months after CTX treatment and 14.0 months after RTX treatment(P=0.505);The relapse rates at the time of 6 months of treatment were 19.23%in group CTX and 5.88%in group RTX(P=0.376);the relapse rates at 1 year were 42.31%in group CTX and 23.08%in group RTX(P=0.304).4.There were no statistically significant differences in steroid dose and the number of relapse between the groups of single-dose RTX and double-dose RTX(P>0.05).5.CD19+B cell recovery occurred 4-7 months after the first dose of RTX treatment.6.There were three cases of respiratory tract infections?1 case of urinary tract infection,and 1 case of acute cellulitis in CTX group.There were Three respiratory tract infections.All of them were cured after symptomatic treatment.The incidence rates of infection in the two groups were 19.23%in group CTX and 17.65%in RTX,There was no statistical significance(P=1.000).No other serious adverse reactions were observed.7.The hospitalization costs of single-dose RTX are significantly less than one course of CTX treatment(P=0.000).Concolusion:Both of CTX and RTX were beneficial to steroid reduction?reducing the frequency of relapse for FRNS or SDNS children at1 year after treatment.And RTX was superior to CTX in steroid reduction.Most children could tolerate CTX or RTX treatment,and no serious adverse reactions have occurred.Patient with repeated RTX infusions(once every 6 months)showed a longer urinary protein remission,but the best number of infusions is for further study.Single-dose RTX and double-dose RTX have similar effects in reducing the frequency of recurrence and assisting steroid reduction.Compared with CTX,the single-dose RTX can ensure short-term efficacy while reducing the cost of hospitalization for children.