Declaration of Competing Interest This study was sponsored by F. Hoffmann-La Roche. Takashi Yamamura served on scientific advisory boards for Biogen, Takeda, Sumitomo, Novartis, and Chugai. He receives consulting fees from Biogen, Takeda, Mitsubishi Tanabe, Novartis, Roche, and Chugai. He carried out contracted research in Mitsubishi Tanabe, Novartis, Chugai, Sanofi, Chiome Bioscience, and Miraca Holdings (within the contract period but no deposit). He received speaker honoraria from Chugai, Takeda, Biogen, and Sumitomo. Brian G. Weinshenker reports consulting fees from UCB Biosciences, Mitsubishi Tanabe, Genentech, and Roche, and speaking fees from Genentech, Roche, and Novartis; he participated on the Attack Adjudication Committee for Alexion and Horizon Therapeutics (formerly MedImmune/Viela Bio). He reports personal fees from Chugai. He has a patent NMO-IgG for diagnosis of neuromyelitis optica with royalties received from RSR Ltd, Oxford University, Hospices Civils de Lyon, and MVZ Labor PD Dr. Volkmann und Kollegen GbR. Michael R. Yeaman received grants from the US National Institutes of Health and the US Department of Defense, and consulting fees from Roche, Horizon, and Alexion. He is a founder and shareholder in NovaDigm Therapeutics, Inc. and Metacin, Inc. He serves on the Genentech-Roche Strategic Scientific Committee for NMOSD and is Chair Medical Advisor to the Guthy-Jackson Charitable Foundation for NMOSD. Jerome De Seze received grants and personal fees from Roche, personal fees from Chugai, and has served on advisory boards in the expert committee for the clinical trial conducted by Chugai. Francesco Patti has served on the scientific advisory boards for Almirall, Bayer, Biogen, Calgene, Merck, Novartis, Roche, Sanofi, and TEVA; he also received speaker honoraria from the aforementioned companies and research grants for his department from Biogen and Merck. Patricia Lobo is an employee of ApotheCom, who is paid to provide medical writing assistance for F. Hoffmann-La Roche Ltd. H.-Christian von Büdingen, Xiujing Kou, and Kristina Weber are employees of F. Hoffmann-La Roche Ltd. Benjamin Greenberg received consulting fees from Alexion, Novartis, EMD Serono, Viela Bio, Genentech/Roche, Greenwich Biosciences, Axon Advisors, Rubin Anders, ABCAM, Signant, IQVIA, Sandoz, Druggability Technologies, Genzyme, and Immunovant. He receives contracted research fees from Clene Nanomedicine. He receives royalties from UpToDate.