What is Neuromyelitis Optica (NMO), also known as Devic's disease?

From the Guidelines

Neuromyelitis optica (NMO) is an autoimmune disorder that requires prompt diagnosis and treatment to prevent permanent neurological damage, and the most effective treatment approach involves a combination of acute management with high-dose intravenous methylprednisolone and long-term management with immunosuppressive medications such as rituximab, mycophenolate mofetil, or azathioprine, as recommended by recent studies 1. The condition is characterized by episodes of optic neuritis and transverse myelitis, which can lead to vision loss, weakness or paralysis in the limbs, and bladder/bowel dysfunction. Key features of NMO include:

• Optic neuritis, which can cause vision loss, pain, and blindness
• Transverse myelitis, which can cause weakness, paralysis, and bladder/bowel dysfunction
• Presence of antibodies against aquaporin-4 (AQP4), a water channel protein found in the central nervous system
• Association with other autoimmune disorders, such as lupus and rheumatoid arthritis Treatment of NMO typically involves:
• Acute management with high-dose intravenous methylprednisolone (1000 mg daily for 3-5 days) followed by oral prednisone taper
• Plasma exchange (5-7 exchanges over 2 weeks) for severe attacks or when steroid response is inadequate
• Long-term management with immunosuppressive medications such as rituximab (375 mg/m² weekly for 4 weeks or 1000 mg given twice, two weeks apart), mycophenolate mofetil (1000-1500 mg twice daily), or azathioprine (2-3 mg/kg/day)
• Newer targeted therapies, such as eculizumab, inebilizumab, and satralizumab, which have shown promise in reducing relapse rates and improving outcomes Regular monitoring of neurological function, medication side effects, and antibody levels is crucial to assess treatment efficacy and adjust the treatment plan as needed 1. Some key points to consider in the diagnosis and treatment of NMO include:
• The importance of early diagnosis and treatment to prevent permanent neurological damage
• The need for regular monitoring of neurological function, medication side effects, and antibody levels to assess treatment efficacy
• The potential benefits and risks of different treatment approaches, including immunosuppressive medications and targeted therapies
• The importance of considering the individual patient's needs and circumstances when developing a treatment plan.

From the FDA Drug Label

1. 4 Neuromyelitis Optica Spectrum Disorder (NMOSD) SOLIRIS is indicated for the treatment of neuromyelitis optica spectrum disorder (NMOSD) in adult patients who are anti-aquaporin-4 (AQP4) antibody positive.

• Eculizumab (IV) is indicated for the treatment of Neuromyelitis Optica Spectrum Disorder (NMOSD) in adult patients who are anti-aquaporin-4 (AQP4) antibody positive 2.
• The drug is specifically approved for use in patients with this condition who have the AQP4 antibody, which is a key factor in the disease.

From the Research

Overview of Neuromyelitis Optica

• Neuromyelitis optica spectrum disorder (NMOSD) is a rare neurologic autoimmune disease with a poor prognosis if left untreated 3.
• NMOSD attacks require an urgent probabilistic anti-inflammatory therapeutic strategy, and inadequately treated attacks result in disability 4.

Treatment Options

• The mainstays of drug treatment for NMOSD have been generic oral immunosuppressants and repurposed monoclonal antibodies that target the interleukin-6 pathway or B cells 3.
• New biologics developed and approved specifically for NMOSD have been added to the treatment options, including azathioprine, mycophenolate mofetil, rituximab, tocilizumab, eculizumab, satralizumab, and inebilizumab 3.
• Treatment regimens for NMOSD attacks include corticosteroids, plasma exchanges, and intravenous immunoglobulins 4.
• Rituximab, azathioprine, and mycophenolate mofetil have been compared in terms of efficacy and safety, with rituximab appearing to be superior in improving disability and reducing relapse in patients with NMOSD 5.

Adverse Events and Prognostic Factors

• Infections, cytopenias, and infusion-related reactions are common adverse events associated with NMOSD treatment 3.
• MOG-antibody seropositivity and short delays to plasma exchange are significantly and independently associated with better recovery and treatment response 4.
• History of a severe attack and disease duration are associated with the risk of relapse after immunotherapy, and late-onset NMOSD patients are more susceptible to motor disability 6.
• The age at onset, disease duration, history of severe attacks, and primary syndromes might be significant prognostic predictors in NMOSD 6.

Diagnosis and Prevention

• The presence of a serum antibody to aquaporin-4 called NMO-IgG is the best predictor of conversion from optic neuritis to clinical definite NMO, but this test is currently only about 75% sensitive 7.
• Suspicion of NMO should be high in patients who present with vision of light perception or worse or who are left with acuity of 20/50 or worse after optic neuritis and in those with simultaneous bilateral optic neuritis or recurrent attacks 7.
• Preventative strategies against relapses currently use broad-spectrum or selective B-lymphocyte immune suppression, but their use is based on small, generally uncontrolled studies 7.