Add-on satralizumab cuts relapse risk in neuromyelitis optica spectrum disorder

Takeaway

• Adding satralizumab, an antibody targeting interleukin-6 receptor, to stable immunosuppressant therapy reduced relapse risk in patients with neuromyelitis optica spectrum disorder (NMOSD) but did not reduce pain or fatigue.

Why this matters

• Lack of safe, effective treatments for this disorder.

Key results

• Median treatment duration during double-blind period: 107.4 weeks.
• Relapse rate: 20% with satralizumab, 43% with placebo (HR, 0.38; 95% CI, 0.16-0.88).
• Findings were similar with multiple imputations for censored data.
• Benefit by anti–aquaporin-4 (AQP4-IgG) status:
  • Significant among seropositive patients (11% vs 43%; HR, 0.21; 95% CI, 0.06-0.75).
  • Not significant among seronegative patients (36% vs 43%; HR, 0.66; 95% CI, 0.20-2.24).
• Groups statistically indistinguishable on change in:
  • Mean visual-analogue scale pain score (difference, 4.08; 95% CI, −8.44 to 16.61).
  • Mean Functional Assessment of Chronic Illness Therapy–Fatigue score (difference, −3.10; 95% CI, −8.38 to 2.18).
• Groups were similar on rates of serious adverse events (90% vs 95%), infections (68% vs 62%).

Study design

• Phase 3 randomised controlled trial among 83 adolescent and adult patients with NMOSD.
• Randomisation: satralizumab vs placebo, added to stable immunosuppressant therapy.
• Main outcome: first relapse.
• Funding: Chugai Pharmaceutical.

Limitations

• Small group sizes.
• Lack of an active comparator.
• Inability to assess differences at weekly intervals.