A, Neuromyelitis optica spectrum disorder relapses and attacks among patients before, during, and after receiving BTZ treatment. The zero on the x-axis represents the first subcutaneous injection of BTZ. On the line of dashes, different clinical courses or relapses are shown. The colored thread under the dashes represents different medications used throughout patient therapy. The arrowheads indicate the treatment option in acute relapse. After receiving 4 cycles of BTZ treatment, all patients continued to receive the treatment of oral prednisone or azathioprine. IV indicates intravenous. Alteration of Expanded Disability Status Scale (EDSS) scores (B) and serum antiaquaporin-4 autoantibody (AQP4-ab) titers (C) among patients with neuromyelitis optica spectrum disorder receiving BTZ treatment during 1-year follow up. The 0 month represents baseline before BTZ was administered. The cutoff of the negative value of the AQP4-antibody, shown by the dotted line, was set at 15.0nM in serum.