Advancements in understanding NMOSD have led to the discovery of new targeted therapies in the past 20 years, but managing the condition still presents significant challenges.
Neuromyelitis optica spectrum disease (NMOSD) is a severe form of multiple sclerosis (MS) that damages the spinal cord and optic nerve. NMOSD presents unique short- and long-term management difficulties. This article, published in the Journal of Neurology, discusses the challenges and advancements in managing NMOSD.
Managing Acute Relapse in NMOSD
Acute relapse management for NMOSD typically involves high-dose corticosteroids followed by a slow taper. However, additional immunotherapy, such as plasma exchange or immunoadsorption, may be necessary for some patients. Rituximab may be used in refractory cases, but its utility as a rescue medication is unclear. Other immunosuppressive agents, cyclophosphamide, may need to be considered for more severe cases.
Immunosuppressive Therapies for NMOSD
Immunosuppressive therapies such as rituximab and three new targeted therapies, eculizumab, satralizumab, and inebilizumab, have shown promise in reducing relapses and preventing relapse-related disability in individuals with NMOSD. While eculizumab is a prohibitively expensive option for many patients, it has a rapid onset of action. Satralizumab has a better safety profile with other immunotherapies and can be self-administered subcutaneously, while inebilizumab requires less immunosurveillance. However, all three targeted therapies are only approved for aquaporin-4 seropositive patients.
Promising Biomarkers for NMOSD Diagnosis and Monitoring
Biomarkers are essential in diagnosing, predicting relapses, and monitoring recovery in individuals with NMOSD. Although 75% of patients are seropositive for AQP4 IgG, serum AQP4 IgG titres may not predict the long-term disease course or response to therapy. Serum neurofilament light chain (sNFL) and glial fibrillary acidic protein (GFAP) are promising biomarkers in detecting relapses and predicting recovery. MRI criteria are useful in diagnosing NMOSD. Combining GFAP and sNFL with other diagnostic markers, like MRI, may be optimal for diagnosing and monitoring the disease and response to treatment.
The Impact of COVID-19 on NMOSD
The COVID-19 pandemic has impacted the care of patients with autoimmune disorders, including NMOSD. According to the COViMS Registry, 16% of NMOSD patients with COVID-19 were hospitalized, 9% required intensive care, and 10% died. Patients with comorbidities like diabetes, hypertension, or obesity had a 6-fold higher risk of poor clinical COVID-19-related outcomes. Registries have shown that the use of immunomodulatory therapies like rituximab and corticosteroids were associated with slightly greater odds of hospitalization and intensive care admissions.
Individualized Treatment Plans for Pregnancy and Lactation in People With NMOSD
Pregnancy and lactation in people with NMOSD require individualized treatment plans that consider the patient’s clinical status and disease severity, as well as medication safety. High-dose nonfluorinated corticosteroids, plasmapheresis, and IVIg are considered safe during the intrapartum period, while azathioprine with or without corticosteroids appears to be safe during breastfeeding.
In the management of NMOSD, preventing relapses is the main objective, which necessitates the identification of reliable biomarkers for anticipating the onset and severity of relapses. Furthermore, healthcare providers must pay attention to vulnerable patient populations, such as pregnant, post-partum, or those at risk of infection.
Costello, F., & Burton, J. M. (2022). Contemporary management challenges in seropositive NMOSD. Journal of Neurology, 269(10), 5674-5681. https://doi.org/10.1007/s00415-022-11241-5