Treatment of MOG antibody associated disorders: results of an international survey

Introduction: Myelin oligodendrocyte glycoprotein antibody associated disorders (MOGAD) include monophasic and relapsing presentations of optic neuritis, transverse myelitis, encephalitis and acute disseminated encephalomyelitis. Disease course is unpredictable at outset, and differs between children and adults. Evidence guiding treatment is limited to small retrospective cohort studies or is extrapolated from neuromyelitis optica spectrum disorders with aquaporin-4 antibodies. Objectives: To survey the current clinical practice of clinicians treating MOGAD Methods: Neurologists worldwide with expertise in treating MOGAD participated in an online survey using 'Survey Monkey', a web-based survey tool (February - April 2019). Results: 52 responses were received (response rate 60.5%) from adult (44.2%, 23/52) and paediatric (21.2%, 11/52) neurologists, and those treating all ages (34.6%, 18/52). Mean number of MOGAD patients under each respondent's care is 31.3±28.7. All treat acute attacks with high dose corticosteroids. If recovery is incomplete, 71.2% (37/52) proceed next to plasma exchange (PE). 45.5% (5/11) of paediatric neurologists use IV immunoglobulin (IVIg) in preference to PE. Following an acute attack, 55.8% (29/52) of respondents typically continue corticosteroids for ⩾3 months; though less commonly when treating children. After an index event 60% (31/51) usually start steroid-sparing immunotherapy (SSIT); after ⩾2 attacks 92.3% (48/52) would start SSIT. Repeat MOG antibody status is used by 52.9% (27/51) to help decide on SSIT initiation. Commonly used first-line SSITs in adults are azathioprine (30.8%, 16/52), mycophenolate mofetil (25.0%, 13/52) and rituximab (17.3%, 9/52). In children, IVIg is the preferred first line SSIT (54.5%; 6/11). Rituximab is the preferred escalation therapy (55.7%, 29/52). Tocilizumab and combination therapies are also frequently used in refractory cases. Treatment response is monitored by MRI (53.8%; 28/52), optical coherence tomography (23.1%; 12/52) and MOG antibody titres (36.5%; 19/52). Regardless of monitoring results, 25.0% (13/52) would not stop SSIT. Factors influencing treatment duration are attack severity/frequency, time from last relapse, MOG-Ab status during follow-up and patient preference. Conclusions: This worldwide survey highlights that current treatment of MOGAD is highly variable. It underlines the need for consensus-based treatment guidelines, while awaiting definitive clinical trials.