2025 年 42 巻 4 号 p. 672-676
Neuromyelitis optica spectrum disorders (NMOSD) are autoimmune neurological disorders of the central nervous system that primarily cause optic neuritis and myelitis. In 2004, disease–specific autoantibodies were discovered, and the following year, their target was identified as aquaporin 4 (AQP4), a water channel abundant in the foot processes of astrocytes. This discovery led to the elucidation of the clinical features and immunopathology, and revealed astrocyte damage caused by AQP4 antibodies.
The number of patients with recurrence of NMOSD has been greatly reduced by the use of steroids. On the other hand, concomitant use of immunosuppressive drugs was necessary, and a wide variety of side effects of steroids were problematic.
With the understanding of the immunopathology of NMOSD, the molecules targeted for treatment were identified, and the development of biologic agents (molecular–targeted drugs) has progressed : since 2019, anti– complement C5 (eculizumab, ravulizumab), anti–IL–6 receptor (satralizumab), anti–CD19 (inebilizumab), and anti–CD20 antibodies (rituximab) are approved for the prevention of relapse in patients with NMOSD. These antibodies are recommended for use in patients with refractory NMOSD due to their high efficacy in preventing relapses, and have recently been actively considered for use in patients who are unable to reduce the dose of steroids.
This article discusses the risks and benefits of biologic agents and steroids in the prevention of NMOSD relapses.
