TY - JOUR T1 - Less frequent rituximab retreatment maintains remission of neuromyelitis optica spectrum disorder, following long-term rituximab treatment JF - Journal of Neurology, Neurosurgery & Psychiatry JO - J Neurol Neurosurg Psychiatry SP - 486 LP - 487 DO - 10.1136/jnnp-2018-318465 VL - 90 IS - 4 AU - Su-Hyun Kim AU - Yeseul Kim AU - Gayoung Kim AU - Na Young Park AU - Hyun-Min Jang AU - Hyun-June Shin AU - Jae-Won Hyun AU - Ho Jin Kim Y1 - 2019/04/01 UR - http://jnnp.bmj.com/content/90/4/486.abstract N2 - Rituximab, a chimeric monoclonal antibody that selectively targets CD20+ B cells, has exhibited robust efficacy and an acceptable safety profile in neuromyelitis optica spectrum disorder (NMOSD).1–3 Previously, we reported that the therapeutic response of B cell depletion varied among 100 patients with NMOSD, which resulted from multiple factors including Fc gamma polymorphism, and that monitoring CD27+ memory B cell appears to improve treatment outcomes via individualised treatment.2 Our treatment strategy has also proven to effectively prevent relapse at a lower cumulative dose, compared with the fixed maintenance therapy every 6 months, in a French cohort.4 Currently, we have a group of patients with NMOSD who have undergone long-term rituximab treatment for more than 7 years. We found that retreatment interval became significantly prolonged over time when we targeted depletion of memory B cells. Here, we analysed clinical outcomes and changes in B cell reconstitution over time, following long-term repeated rituximab treatment.Through December 2017, sixty-eight patients with NMOSD had been treated with rituximab for at least 7 years. Twenty-one patients who had been treated with mitoxantrone, prior to rituximab, were excluded; the remaining 47 patients were included. Written informed consent was obtained from all patients. After induction therapy, patients received a single infusion of rituximab, at a dose of 375 mg/m2, as maintenance therapy; this was performed whenever the frequency of re-emerging CD27+ memory B cells in peripheral blood mononuclear cells (PBMC) exceeded 0.05% as revealed by flow cytometry for the initial 2 years, and, subsequently, when the frequency exceeded … ER -