Objective: To report first experiences with interleukin 6 receptor inhibition in therapy-resistant neuromyelitis optica (NMO).
Design: Retrospective case series.
Setting: Neurology department at a tertiary referral center.
Patients: Patients with an aggressive course of NMO switched to tocilizumab after failure of anti-CD20 therapy.
Main outcome measures: Annualized relapse rate and disability progression measured by the Expanded Disability Status Scale.
Results: We report 3 female patients with a median age of 39 years (range, 26-40 years) and aquaporin 4-positive NMO. All patients had been treated with different immunosuppressive and immunomodulating agents, followed by 1 to 3 cycles of rituximab. Despite complete CD20-cell depletion during rituximab therapy, the median annualized relapse rate was 3.0 (range, 2.3-3.0) and the median Expanded Disability Status Scale score increased from 5.0 (range, 4.5-7.0) to 6.5 (range, 5.0-7.0). After the switch to tocilizumab (median duration of therapy, 18 months), the median annualized relapse rate decreased to 0.6 (range, 0-1.3). A total of 2 relapses occurred; however, they were mild and there were no changes in clinical disability.
Conclusions: Interleukin 6 receptor-blocking therapy can be effective in therapy-resistant cases of NMO. Larger controlled studies are needed to confirm the efficacy of tocilizumab.