LAUSR

OBJECTIVE To evaluate disease activity according to rituximab (RTX) induction and maintenance regimens in a multicenter real-life dataset of NMOSD patients. METHODS This is an observational-retrospective multicentre study including patients with NMOSD treated with RTX in 21 Italian and 1 Swiss centers. Demographics, relapse rate and adverse events over the follow-up were summarized taking into account induction strategy (two-1 g infusions at a 15-day interval (IND-A) vs. 375 mg/m2/week infusions for one month (IND-B)) and maintenance therapy (regimen A (M-A) with fixed time-points infusions vs. regimen B (M-B) based on cytofluorimetric driven reinfusion regimens, the least further subdivided according to CD19+ B cells (M-B1) or CD27+ memory B cells (M-B2) monitoring). RESULTS 131 subjects were enrolled, 127 patients completed the induction regimen and 119 patients had at least one follow-up visit and were included in the outcome analysis. Median follow-up was 1.7 years (range 0.1-11.6). Annualized relapse rate (ARR) was 1.7 in the year before RTX start and decreased to 0.19 during the follow-up. Both ARR and Time to first relapse (TTFR) analysis showed a trend toward an increased disease activity for IND-B and M-A. No patients with MT-B2 experienced relapses during the follow-up. Number of relapses in the year before RTX initiation and having received a previous treatment were significantly associated with higher ARR and reduced TTFR in the multivariate analysis. INTERPRETATION We confirm RTX efficacy in NMOSD patients. Use of specific induction and maintenance protocols is warranted in order to foster RTX efficacy and to reduce costs and side effects.