AB0459 Treatment of systemic autoimmune diseases with rituximab: safety data

Background Systemic autoimmune diseases (SAD) have traditionally been treated with steroids and immunosuppressants, but not all patients respond to this strategy. Rituximab (RTX) has been used in several SAD with favorable efficacy and safety results; there are only reports of isolated clinical experiences of small series of patients. The description of this drug safety data in daily clinical practice may be relevant. Objectives To describe the adverse events and the hospital admissions during the treatment of a series of patients with SAD with RTX. Methods Demographic data, related to disease and treatment, response and safety variables were included. We use the EULAR definitions of partial response (improvement of at least 50% of the main manifestations) and complete response (disappearance of the manifestations), because of the heterogeneity of the SAD. Results We included 53 patients, 90.6% were women; the mean age at diagnosis was 31.42±14.33 years; and the median duration of disease at the onset of RTX 1.99 (0–7.5) years. Patients received a median of 2 cycles (1–3; min -1, max 12); and the median interval between cycles was 14.81 months (6–15.75;min 6, max 120). The SAD were SLE with 23 cases (43.4%), systemic sclerosis with 7 cases (13.2%), Sjogren9s syndrome with 6 cases (11.3%), vasculitis with 5 cases (9.4%), Still disease with 3 cases (5.7%), autoinmune cytopenias with 3 cases (5.7%), dermatomyositis with 2 cases (3.8%), Behcet9s disease with 2 cases (3.8%), IgG4 disease with 1 case (1.9%) and sarcoidosis with 1 case (1.9%). A partial response was observed in 27 patients (50.9%) and complete in 20 patients (37.7%). There was no response in 6 of the 53 patients (11.3%). Adverse events were detected in 15 of the 53 patients (28.3%) and 20 were hospitalized (37.7%) during the treatment with RTX (Table 1). Three patients developed hypogammaglobulinemia, only one of them was associated with recurrent respiratory infections and even hospitalized in one occasion. Febrile neutropenia was detected in 2 patients, and one of them required admission. Three patients were diagnosed with pneumonia and admitted for supportive and antibiotic treatment. Three other patients suffered gastroenteritis requiring admission in one of them. In two cases, low respiratory infections were repeated requiring admission on 7 occasions. There was also recurrent otitis and a severe hypersensitivity reaction. Conclusions The most frequent adverse event were the infectious, mainly respiratory tract infections followed by an infusion reaction. No patient developed opportunistic diseases. This findings are similar than observed in other studies on patients with SAD treated with RTX. Infusion reactions are becoming less frequent, due in part to premedication. We are dealing with a large number of patients with refractory EAS treated with RTX, so the data obtained from this study show an acceptable safety profile. References Ramos-Casals M, Garcia-Hernandez FJ, de Ramόn E, Callejas JL, Martinez-Berriotxoa A, Pallares L, et al. Off-label use of rituximab in 196 patients with severe, refractory systemic autoimmune diseases. Clinical and experimental rheumatology 2010;28(4):468–76. Disclosure of Interest None declared