TY - JOUR T1 - Humoral immunity to SARS-CoV-2 mRNA vaccination in multiple sclerosis: the relevance of time since last rituximab infusion and first experience from sporadic revaccinations JF - Journal of Neurology, Neurosurgery & Psychiatry JO - J Neurol Neurosurg Psychiatry DO - 10.1136/jnnp-2021-327612 SP - jnnp-2021-327612 AU - Marton König AU - Åslaug Rudjord Lorentzen AU - Hilde Marie Torgauten AU - The Trung Tran AU - Stine Schikora-Rustad AU - Eline Benno Vaage AU - Åse Mygland AU - Stig Wergeland AU - Jan Aarseth AU - Ingeborg Aase S Aaberge AU - Øivind Torkildsen AU - Trygve Holmøy AU - Tone Berge AU - Kjell-Morten Myhr AU - Hanne Flinstad Harbo AU - Jan Terje Andersen AU - Ludvig Andre Munthe AU - Arne Søraas AU - Elisabeth Gulowsen Celius AU - John Torgils Vaage AU - Fridtjof Lund-Johansen AU - Gro Owren Nygaard Y1 - 2021/10/20 UR - http://jnnp.bmj.com/content/early/2021/11/08/jnnp-2021-327612.abstract N2 - Introduction The effect of disease-modifying therapies (DMT) on vaccine responses is largely unknown. Understanding the development of protective immunity is of paramount importance to fight the COVID-19 pandemic.Objective To characterise humoral immunity after mRNA-COVID-19 vaccination of people with multiple sclerosis (pwMS).Methods All pwMS in Norway fully vaccinated against SARS-CoV-2 were invited to a national screening study. Humoral immunity was assessed by measuring anti-SARS-CoV-2 SPIKE RBD IgG response 3–12 weeks after full vaccination, and compared with healthy subjects.Results 528 pwMS and 627 healthy subjects were included. Reduced humoral immunity (anti-SARS-CoV-2 IgG <70 arbitrary units) was present in 82% and 80% of all pwMS treated with fingolimod and rituximab, respectively, while patients treated with other DMT showed similar rates as healthy subjects and untreated pwMS. We found a significant correlation between time since the last rituximab dose and the development of humoral immunity. Revaccination in two seronegative patients induced a weak antibody response.Conclusions Patients treated with fingolimod or rituximab should be informed about the risk of reduced humoral immunity and vaccinations should be timed carefully in rituximab patients. Our results identify the need for studies regarding the durability of vaccine responses, the role of cellular immunity and revaccinations. ER -