Experience with tocilizumab in patients with neuromyelitis optica spectrum disorders

Neuromyelitis optica spectrum disorders (NMOSD) are immune-mediated inflammatory disorders of the central nervous system involving astrocytes, B lymphocytes, anti-aquaporin 4, and such inflammatory mediators as interleukin-6. Several immunosuppressants are used in their treatment. Tocilizumab, an interleukin-6 receptor antagonist, may be a treatment option.

We performed an observational, retrospective study analysing parameters of effectiveness (annualised relapse rate, disability, and radiological progression) and safety of tocilizumab in patients with NMOSD in whom previous immunosuppressant treatment had failed. We aimed to evaluate the effectiveness and safety of tocilizumab in clinical practice in patients with NMOSD not responding to other immunosuppressants.

Five patients with NMOSD were analysed. Sixty percent of patients were women; mean age at diagnosis was 50±5.3 years and mean progression time was 4.5±3.6 years. Previously administered immunosuppressants were rituximab (in all 5), cyclophosphamide (2), and azathioprine (1). Mean time of exposure to tocilizumab was 2.3±1 years. Mean annualised relapse rate was 1.8±1.3 in the year prior to the introduction of tocilizumab and 0.2±0.4 the year after (P<.05), representing a reduction of 88.9%.

In our experience, tocilizumab is safe and effective in patients with NMOSD showing no response to other immunosuppressants.