Drug Treatment of Neuromyelitis Optica Spectrum Disorders: Out with the Old, in with the New?

Abstract

Introduction: Neuromyelitis optica spectrum disorders (NMOSD) are rare neuroinflammatory demyelinating diseases of the CNS, mainly affecting optic nerves, spinal cord and brainstem regions. The diagnosis depends on clinical symptoms, MRI findings and the detection of autoantibodies against the water channel aquaporin 4 (AQP4-Ab). This autoantibody is particularly important for diagnostic sensitivity and specificity and further sets the course for major therapeutic decisions. Due to a relapsing course with the accumulation of disability, relapse prevention by immunotherapy is crucial in NMOSD. Until recently, disease-modifying agents specific to NMOSD were not available, and patients were treated with various immunosuppressive drugs and regimens-with variable success. Fortunately, since 2019, three new therapeutic antibodies have entered the market. Areas Covered: We aim to shortly summarise the pathogenesis and biological targets for acute and preventive therapy of adult NMOSD. We will focus on conventional immunotherapies and the recently approved novel biological drugs satralizumab, eculizumab and inebilizumab, and conclude with a brief outlook on future therapeutic approaches. Expert Opinion: Although satralizumab, eculizumab and inebilizumab are a breakthrough concerning short-term efficacy, important questions on their future use remain open. There is no data from head-to-head comparisons, and data on long-term safety and efficacy of the new medicines are pending. Whether any of the biologics are efficacious in AQP4-Ab negative NMOSD patients is not yet known-as is how they will succeed in non-responders to conventional immunotherapies. Further, (autoimmune) comorbidities, affordability, and market availability of drugs may be decisive factors for choosing treatments in the near future. We are fortunate to have these new drugs available now, but they will not immediately supersede established off-label drugs in this indication. It is still too early to definitively revise the treatment algorithms for NMOSD-although we are probably on the way.

Clinical profile, imaging features and short term visual outcomes of Indian optic neuritis patients with and without seromarkers for myelin oligodendrocyte glycoprotein and neuromyelitis optica

“…In our country, these drugs are used restrictedly due to poor availability and higher cost. [ 25 ] Similarly, more targeted therapies for MOG AD are expected to evolve in future. Disease-modifying therapy (DMT) like interferon and glatiramer acetate should be considered for ON with MS features only.…”

Long-term safety of satralizumab in neuromyelitis optica spectrum disorder (NMOSD) from SAkuraSky and SAkuraStar

“…Until 2019, no treatments were approved for NMOSD (Selmaj and Selmaj, 2019), and off-label non-specific immunosuppressive therapies (ISTs) have historically been the mainstay of maintenance treatment (Brod, 2020;Held et al, 2021;Jarius et al, 2020).…”

NMOSD—Diagnostic Dilemmas Leading towards Final Diagnosis

“…There are also a few drugs under development: aquaporumab, bortezomib, revulizumab, sivelestat and ublituximab. Appropriate treatment should be provided for each patient individually, but further recommendations for the use of new drugs are still under development [ 65 , 66 ].…”