P186 Efficacy and safety of rituximab in the treatment of systemic vasculitis: experience at a single centre

Background Rituximab is a monoclonal chimeric antibody targeting the mature B cell molecule CD20, expressed on the cell surface. It is licenced and widely used in the treatment of autoimmune diseases, including the ANCA associated vasculitides and rheumatoid arthritis. The efficacy and safety of rituximab in rare diseases requires ongoing appraisal. Methods We interrogated the records of 62 consecutive patients treated with rituximab for small vessel systemic vasculitis at our unit over the last 3 years, using a contemporaneously maintained central database, as well as individual electronic patient records. Results The patient demographic data, and main results are presented in Table 1. 31 (50%) of the patients treated with rituximab were female, and the indication for treatment in most cases was ANCA associated vasculitis (77.4%). After a mean follow up period of 2.04 years, the mean reduction in BVAS was 1.64 (3.83). 5 severe adverse events were recorded, defined as death or hospitalisation potentially related to treatment with rituximab. 3 patients died of respiratory sepsis, 1 experienced a wound infection, and 1 experienced an ischaemic colon. Four patients were noted to have low immunoglobulins. Conclusion Rituximab is an effective treatment for many patients with systemic, small vessel vasculitis. Understanding the safety profile of this drug in the context of our cohort is challenging, given the significant morbidity associated with the underlying disease, as well as the age profile and concomitant immunosuppressive medications. Continued surveillance regarding efficacy and safety of rituximab in the small vessel systemic vasculitides remains invaluable. Disclosures C. Orr None. A. Verdiyeva None. N. Ahmad None. H. Ariff None. R. Luqmani None.