Disease exacerbation after rituximab induction in neuromyelitis optica

Abstract

OBJECTIVE: To report clinical ,epidemiological and safety data of Neuromyelitis Optica Spectrum Disorders (NMOSD) and Myasthenia Gravis (MG) Argentinian patients treated with rituximab (RTX) . BACKGROUND: NMOSD is a severe inflammatory disease of the central nervous system while MG is an autoimmune disorder of the neuromuscular junction. RTX, an anti-CD20 monoclonal antibody, was highly efficacious in reducing relapse rates in NMOSD and improvement MG refractory in observational case series. Despite the favorable efficacy, some patients experienced clinical relapses after RTX induction. DESIGN/METHODS: We retrospectively reviewed the medical records of patients affected by NMOSD and MG attending Ramos Mejia Hospital in Buenos Aires, Argentina from January 2007 to July 2015. RESULTS: We recruited 55 NMOSD patients and 130 MG patients. Out of 11/55 NMOSD and 3/130 MG patients were treated with RTX. The treatment consisted of a total dose of 2 g of RTX IV divided into 2 biweekly infusions. 5 of 11 (45[percnt]) patients with NMOSD and 1 of 3 (33[percnt]) patients with MG attending at our centre, experienced disease exacerbation within the first month of their first RTX infusion. Average age at RTX induction was 39.3 years (range 21-59 years), average disease duration was 7.2 years (range 1.5-21 years), and all patients were women. Among NMOSD patients, the location of relapses was spinal cord in 2 patients, optic nerves in the other 2 patients. One patient also developed encephalopathy with multiple new gadolinium-enhancing lesions throughout the cerebrum. The patient with MG experienced muscle weakness during the first week post-induction. CONCLUSIONS: Our data showed an increase risk of relapse after RTX infusion. Although these observational data are insufficient to, it seems plausible that patients are at increased risk for post-RTX relapse. Perhaps overlap of immunosuppression with RTX would yield better results.