Efficacy and safety of off-label use of rituximab in refractory lupus: data from the Italian Multicentre Registry

OBJECTIVES: To evaluate the efficacy and safety of rituximab (RTX) in patients with systemic lupus erythematosus (SLE) refractory to standard therapy in the clinical practice setting. METHODS: 145 SLE patients (ACR criteria) were treated with RTX in 11 Italian Centres: 118 with two infusions (1 g), two weeks apart; 27 with 4 infusions (375 mg/m2), one week apart, followed in 10 cases by two further doses, after 1 and 2 months. Systemic complete response (CR) was defined as European Consensus Lupus Activity Measurement (ECLAM) score ≤1 and partial response (PR) as 1< ECLAM ≤3. Renal CR (RCR) and renal PR (RPR) were defined according to EULAR recommendations for management of lupus nephritis. RESULTS: Data from 134 (92.4%) patients were available. The mean±SD follow-up was 27.3±18.5 months. After the first course of RTX, CR or PR were observed in 85.8% and CR in 45.5% of cases; RCR or RPR in 94.1% and RCR in 30.9% of patients after 12-month follow-up. Disease flares occurred in 35.1% and renal flares in 31.2% of patients during observational period. Among patients retreated, CR or PR were observed in 84.4% and CR in 57.8% of cases. Adverse events, infections, and infusion reactions occurred after first RTX course in 23.8%, 16.4%, and 3.8% of patients and after retreatment in 33.3%, 22.2% and 11.1%, respectively. No severe infusion reactions or deaths occurred. CONCLUSIONS: Data from Italian multicentre RTX Registry confirmed the efficacy and safety of RTX in SLE patients refractory to standard treatment in clinical practice setting.