AB1024 USE,EFFICACY AND LONG TERM SAFETY OF RITUXIMAB IN PEDIATRIC RHEUMATIC DISEASES: SINGLE CENTER EXPERIENCE FROM NORTH INDIA

Background Rituximab(RTX) is used in pediatric rheumatic diseases as an off label indication.There is paucity of data on safety and long term efficacy in countries with high burden of infectious diseases. Objectives 1. To study the use and safety of RTX in pediatric rheumatic diseases 2. To assess the long term efficacy of RTX in pediatric systemic lupus erythematosus(pSLE). Methods Data of all children who received RTX was collected on standardized collection forms.This data set was reviewed.Children with pSLE who were given RTX were included for efficacy analysis.Screening, use and safety were evaluated for all patients. Results USE: Rituximab was given to 4 children with polyarticular juvenile idiopathic arthritis(PJIA)(4/145=2.7%) and 17 children with pSLE(17/225=7.5%).In children with PJIA, RTX was used as third line treatment, who failed methotrexate and TNF inhibitor therapy. In pSLE, lupus nephritis was the primary indication for RTX(56%), vasculitis(17%), neuropsychiatric SLE and refractory cytopenias(12% each) and aggressive polyarthritis with steroid dependence( 5%). SAFETY: Pre-biologic screen for HIV, Hepatitis B and C and tuberculosis was negative. Total immunoglobulinG level was assayed prior to RTX for all children. CMV PCR was done in 11/17 pSLE patients. No immediate or delayed anaphylaxis was noted. No child had reactivation of herpes zoster.There was no mortality in this cohort. EFFICACY: Studied in 17 children with pSLE over 21 episodes of RTX(2 received 3 cycles of RTX over 5 years).Median age at RTX use was 13.66 years(range 6.58-21.66 years).Median duration of follow up was 48 months(range 3-120 months).During long term follow up 14 patients didnot have any disease flare. Three(17.6%) flared and required cyclophosphamide/second cycle of RTX. Mean dose of prednisolone prior to RTX was 0.7mg/kg/day while that at 1 year post RTX was 0.065mg/kg/day(p value 0.001) and at 2 years was 0.05mg/kg/day(p value 0.003). Mean SLE disease activity index 2K(SLEDAI-2K) prior to RTX was 16.25 while that at 1 year post RTX was 1.25(p value 0.004), at 2 years was 2( p value 0.004) and at 3 years was 0.85(p value 0.028). Conclusion We conclude that RTX is efficacious for use in severe spectrum of pSLE and is relatively safe to use even in a developing country like ours with huge infectious disease burden. References [1] Gladman DD, Ibanez D, Urowitz MB (2002) Systemic lupus erythematosus disease activity index 2000. J Rheumatol 29:288–291 Disclosure of Interests None declared