What is the FDA-approved treatment for pediatric patients with Neuromyelitis Optica Spectrum Disorder (NMOSD)?

FDA-Approved Treatment for Pediatric NMOSD

Currently, there are NO FDA-approved treatments specifically for pediatric patients (under 18 years) with NMOSD, though four medications are approved for adults with AQP4-IgG positive NMOSD: eculizumab, ravulizumab, inebilizumab, and satralizumab. 1, 2

Current FDA-Approved Medications (Adult Indications Only)

The following medications are FDA-approved for adult patients with AQP4-IgG positive NMOSD:

• Eculizumab (anti-complement therapy): Demonstrated over 95% relapse-free rates during follow-up periods 3, 4
• Ravulizumab (anti-complement therapy): Similar efficacy to eculizumab with less frequent dosing 3, 4
• Inebilizumab (anti-CD19 B-cell depleting therapy): Effective in reducing relapse rates 3, 2
• Satralizumab (anti-IL-6 therapy): Shown efficacy in both seropositive and seronegative NMOSD 3, 2

Pediatric Treatment Approach (Off-Label)

Acute Attack Management

• High-dose intravenous methylprednisolone (IVMP) at 1000 mg/day for 3-5 days should be initiated immediately, as delays beyond 2 weeks are associated with poorer outcomes and increased risk of severe neurological deficit 3, 5
• Plasma exchange (PLEX) should be initiated early in severe attacks or when steroid response is inadequate, with clinical improvement in 79.2% of NMOSD patients 3, 5

Long-Term Maintenance (Off-Label Options)

• Rituximab remains the most effective off-label first-line treatment for pediatric NMOSD, demonstrating superior reduction in relapse rates compared to azathioprine and other immunosuppressants, with dosing at 375 mg/m² weekly for 4 weeks or 1000 mg × 2 weeks apart 3, 5
• Mycophenolate mofetil (MMF) at 1-3 g/day shows significant decreases in EDSS scores with better tolerability than azathioprine 3, 5

Emerging Evidence for Pediatric Use

Inebilizumab in Pediatric Patients

A 2025 case series demonstrated that inebilizumab was safe and prevented relapses in four pediatric patients with AQP4-IgG positive NMOSD, with all patients tolerating two courses well without significant side effects or relapses 1. This represents the strongest recent evidence for off-label use of FDA-approved biologics in children.

Eculizumab in Pediatric Patients

A 2025 case report showed that eculizumab was safe and effective in treating an acute attack in a 10-year-old with AQP4-IgG positive NMOSD, resulting in near-complete recovery from severe LETM extending from C2 to the conus medullaris 6. However, the patient experienced relapse during transition to rituximab, highlighting the need for caution when switching from highly effective medications 6.

Critical Treatment Considerations

Common pitfalls to avoid:

• Delaying acute treatment beyond 2 weeks significantly worsens outcomes 3
• Failing to initiate PLEX early in severe cases 3
• Discontinuing maintenance therapy prematurely, as 50-60% of patients relapse during corticosteroid dose reduction 3, 5
• Misdiagnosing as multiple sclerosis and using MS medications, which may worsen NMOSD 5

Monitoring requirements:

• Regular ophthalmological evaluations including visual acuity, visual fields, and funduscopy 3
• Tracking EDSS scores at each visit to objectively measure disability progression 3, 5
• AQP4 antibody level monitoring may help assess treatment efficacy 5