Treatment of neuromyelitis optica spectrum disorders

A Comparative Review of Typical and Atypical Optic Neuritis: Advancements in Treatments, Diagnostics, and Prognosis

Optic neuritis (ON) is a debilitating condition that through various mechanisms, including inflammation or demyelination of the optic nerve, can result in partial or total permanent vision loss if left untreated. Accurate diagnosis and promptly initiated treatment are imperative related to the potential of permanent loss of vision if left untreated, which can lead to a significant reduction in the quality of life in affected patients. ON is subtyped as "typical" or "atypical" based on underlying causative etiology. The etiology of ON can be differentiated when appropriate diagnostic testing is performed. Using history taking, neuroimaging, and visual testing to localize the underlying pathology of ON in a time-sensitive manner is critical in mitigating these unsatisfactory outcomes. Herein, we examine the differences in presentation, pathophysiology, and treatments of typical ON causes, like multiple sclerosis (MS), and atypical causes such as neuromyelitis optica spectrum disorder (NMOSD) and myelin oligodendrocyte glycoprotein (MOG)-immunoglobulin G (IgG) ON. The present investigation places focus on both neuroimaging and visual imaging in the differentiation of ON. Additionally, this review presents physicians with a better understanding of different presentations, treatments, and prognoses of ON.

Monoclonal antibodies in neuro-ophthalmology

Neuro-ophthalmologic diseases include a broad range of disorders affecting the afferent and efferent visual pathways. Recently, monoclonal antibody (mAb) therapies have emerged as a promising targeted approach in the management of several of these complex conditions. Here, we describe the mechanism-specific applications and advancements in neuro-ophthalmologic mAb therapies. The application of mAbs in neuro-ophthalmologic diseases highlights our increasing understanding of disease-specific mechanisms in autoimmune conditions such as neuromyelitis optica, thyroid eye disease, and myasthenia gravis. Due to the specificity of mAb therapies, applications in neuro-ophthalmologic diseases have yielded exceptional clinical outcomes, including both reduced rate of relapse and progression to disability, visual function preservation, and quality of life improvement. These advancements have not only expanded the range of treatable neuro-ophthalmologic diseases but also reduced adverse events and increased the response rate to treatment. Further research into neuro-ophthalmologic disease mechanisms will provide accurate and specific targeting of important disease mediators through applications of future mAbs. As our understanding of these diseases and the relevant therapeutic targets evolve, we will continue to build on our understanding of how mAbs interfere with disease pathogenesis, and how these changes improve clinical outcomes and quality of life for patients.

New advancements in the management of Neuromyelitis Optica spectrum disease: literature review

Neuromyelitis Optica spectrum disorder (NMOSD) is a relapsing autoimmune disease of the central nervous system (CNS) where aquaporin-4 water channels are the antigenic target of the disease. The spectrum of the disease involves regions of the CNS where the water channel is widely expressed including the spinal cord, the optic nerve, dorsal medulla, brainstem, and thalamus/hypothalamus. Management of NMOSD includes acute as well as long term treatment. Acute symptoms are typically treated with intravenous corticosteroids and/or plasma exchange while long-term treatment involves the use of immunosuppression/immune modulation. The year 2019 is thought to be the "year of the NMOSD" as three new medications became available for this devastating disease. In this review, FDA approved NMOSD medications are discussed.

Factors associated with the misdiagnosis of neuromyelitis optica spectrum disorder

BACKGROUND

Neuromyelitis optica spectrum disorder (NMOSD) is a rare autoimmune condition that is associated with severe disability. Approximately 40% of individuals are misdiagnosed with multiple sclerosis (MS) or other diseases. We aimed to define factors that influence the misdiagnosis of people with NMOSD and provide strategies for reducing error rates.

METHODS

A retrospective study was performed involving all people with a confirmed diagnosis of NMOSD within a single academic institution. Comprehensive clinical timelines were constructed for each individual that included presenting symptoms, provider type and timing of evaluations, aquaporin 4-IgG (AQP4) results, and MRI scans. Two-sample comparisons of continuous and categorial variables were performed for people accurately diagnosed with NMOSD and those originally misdiagnosed with another medical condition. A subanalysis of only AQP4-IgG positive people was also performed.

RESULTS

The study cohort included 199 people fulfilling International Panel criteria for NMOSD with 71 people (62 female; mean age at first symptom presentation (standard deviation (SD)) = 32.8 years (y) (SD 16.1)) being initially misdiagnosed and 128 people (106 female; 41.14y (SD 15.41)) who were accurately diagnosed. Of the 199 people with NMOSD, 166 had a positive serostatus. Identified factors associated with misdiagnosis, regardless of AQP4-IgG serostatus, were the presence of protracted nausea/vomiting/hiccups without any accompanying neurological symptoms, 23 (32.4%) versus 16 (12.5%) (p = 0.001), a longer median (range) time to see a neuroimmunology specialist 4.2y (0.14-31.8) versus 0.5y (0.0-21.2) (p<0.0001), and a delay in acquiring an MRI study, 4.7y (0.0-27.3) versus 0.3y (0.0-20.2) (p<0.0001). A greater proportion of people misdiagnosed were identified with a negative live-cell based AQP4-IgG serum test result, 13/13 (100%) versus 22/114 (19.3%) (p<0.0001). Additionally, the mean (SD) time between a first negative and successive live-cell based AQP4-IgG positive test result was greater for people misdiagnosed with another condition, 3.9y (SD 5.0) versus 1.5y (SD 2.1) (p = 0.01). Although not significant between groups, a rash was also reported in 63/199 people with NMOSD, with 31/63 having an anti-nuclear antibody titer ≥ 1:160.

CONCLUSION

Defined factors can help guide both generalists and specialists in the pursuit of strategies aimed at efficiently diagnosing those with NMOSD such that effective care can be delivered.

Effectiveness and Safety of Immunosuppressive Drug Therapy for Neuromyelitis Optica Spectrum Disorders: An Overview of Meta-Analyses and Systematic Reviews

OBJECTIVE

This study aims to provide an overview of meta-analyses and systematic reviews on the effectiveness and safety of immunosuppressive drug therapy for neuromyelitis optica spectrum disorders (NMOSD) by evaluating the methodological quality and reporting quality of reviews.

METHODS

The Chinese National Knowledge Infrastructure (CNKI), WanFang Data, China Science and Technology Journal Database, Web of Science, the Cochrane Library, PubMed, and Embase databases were searched to collect systematic reviews or meta-analyses on the effectiveness and safety of immunosuppressive therapy for NMOSD from inception to December 2, 2021. Two researchers independently screened reviews and extracted data. Any differences in the procession of review assessment between the two researchers were re-evaluated, and the disagreement was resolved by discussion with other researchers. The following data were extracted: author, year of publication, the country where the study was conducted, study type, the number of included studies, sample size, risk bias tools, medication of immunosuppressive therapy, and main outcomes. Then, the AMSTAR-2, which is a critical appraisal tool for systematic reviews (2nd edition), and Grades of Recommendation, Assessment, Development and Evaluation (GRADE) were used to evaluate the methodological quality and reporting quality of evidence. A comprehensive analysis was conducted on the outcomes for all included reviews.

RESULTS

A total of 15 reviews were included. Of the included reviews, 3 were systematic reviews, 7 were meta-analyses, and 5 were systematic reviews and meta-analyses. According to the AMSTAR-2 criteria, 6 studies had high quality, 1 study had moderate quality, 4 studies had low quality, and 4 studies had critically low quality. Based on the GRADE, neither evidence quality for effectiveness nor safety was high.

CONCLUSION

Immunosuppressive drug therapy is effective for patients with NMOSD, but its safety is controversial. Due to the poor quality of evidence, reliability needs to be considered. Thus, large sample, multi-center, double-blind, randomized controlled studies are still needed in the future.

Autologous hematopoietic stem cell transplantation in neuromyelitis optica spectrum disorder: A systematic review and meta-analysis

INTRODUCTION

Treatment options for neuromyelitis optica spectrum disorder (NMOSD) are corticosteroids, immunosuppressive drugs, emerging monoclonal antibodies, rituximab, eculizumab, satralizumab, and inebilizumab. Due to disabling and deadly nature of NMOSD, there is a great motivation among physicians for finding new treatment options. Recently, several studies have been conducted on the therapeutic effects of autologous hematopoietic stem cell transplantation (AHSCT) on NMOSD patients.

METHODS

Several databases including PubMed, Scopus, Web of Science, and Google scholar were searched for studies on AHSCT in NMOSD patients.

RESULTS

After screening titles and abstracts, and reviewing full texts, nine studies with 39 severe cases of NMOSD met the criteria of our study. The pooled standardized mean difference (SMD) for EDSS score before and after treatment was -0.81 (95 %CI:-1.07, -0.15; Q = 1.99, P = 0.58, I2 = 0 %). Also, the PFS and RFS were 69 % and 53 % respectively (PFS: 69 %, 95 %CI 42 %, 96 %; Q = 8.63, P = 0.01, I2 = 73.07 %; RFS: 53 %, 95 %CI 27 %, 79 %; Q = 12.33, P = 0.01, I2 = 71.87 %). Also, there were three cases with secondary autoimmune diseases including myasthenia gravis, hyperthyroidism, and thyroiditis.

CONCLUSION

According to the present study, AHSCT could be an alternative therapy for NMOSD in severe cases instead of conventional immunotherapies. However, physicians should pay attention to its serious complications. The diversity of results from the published trials on the efficacy and safety of AHSCT calls for further investigations on determining the ideal AHSCT conditioning and the characteristics of patients.

Neuromyelitis optica spectrum disease coexisting with subacute combined degeneration: a case report

Background

Subacute combined degeneration (SCD) is a demyelinating disease characterized by vitamin B12 deficiency related segmental degeneration of the dorsal or lateral columns of the spinal cord. However, few cases have been reported as a comorbidity of SCD and neuromyelitis optica spectrum disease (NMOSD).

Case presentation

Herein, we describe a female patient (61-year-old) who had sensory deficits, paresthesia, and weakness of the distal extremities for over 2 months. She then received an initial diagnosis of SCD with typical inverted “V-sigh” hyperintensities over the posterior aspect of the spinal cord in magnetic resonance imaging (MRI - T2-weighted imaging), as well as megaloblastic anaemia in blood examinations. From the past history, there was no evidence of a dietary deficiency or gastric abnormalities. However, traditional treatment with vitamin B12 supplementation was ineffective. Hence, a demyelinating antibody examination showed that she had antibodies targeting aquaporin 4 (AQP4) in both the cerebrospinal fluid and serum, leading to the diagnosis of NMOSD. Her clinical symptoms were obviously improved after treatment with intravenous glucocorticoids.

Conclusion

People who have nutritional deficiency or altered gastrointestinal function are more likely to develop SCD. This case raises the awareness that the poor therapeutic effects of simple vitamin B12 supplementation could be explained by immunoreactions against AQP4. A better recognition will be of great importance for the correct diagnosis of the comorbidity, as well as for essential treatment and even a better prognosis.

Immunosuppressant and Neuromyelitis Optica Spectrum Disorder: Optimal Treatment Duration and Risk of Discontinuation

BACKGROUND

Preventing relapse by immunosuppressants (IS) is critical for prognosis of neuromyelitis optica spectrum disorder (NMOSD); however, the optimal duration of IS treatment is still under discussion.

OBJECTIVE

To explore the optimal duration of IS treatment and the risk of IS discontinuation for NMOSD.

METHOD

We conducted this cohort study at a major neurological center that housed the largest NMOSD database in South China. Eligible participants were patients with NMOSD undergoing IS treatment. The main outcome measures were changes in relapse risk based on IS treatment duration, clinical outcomes, and predictors of relapse following IS discontinuation.

RESULTS

In total, 343 patients were included in this study. The duration of IS treatment was strongly associated with a decrease in relapse risk (hazard ratio [HR] 0.53, p<0.001). Continuous IS treatment resulted in decreased relapse HRs within 5 years of receiving IS medication, with a mild rebound starting at 5 years. Rituximab reduced the risk of NMOSD relapse to approximately zero within 3 years. The rate of relapse after IS withdrawal was high (77.5%). As opposed to other IS, a delayed relapse following rituximab (RTX) withdrawal was observed in this study. Longitudinal extensive transverse myelitis (LETM) (HR=2.023, p=0.006) was associated with a higher risk of relapse after IS discontinuation.

CONCLUSIONS

Long-term IS medication for NMOSD is generally suitable. Patients with LETM had a higher risk of relapse after IS discontinuation. Future studies should explore individualized strategies of RTX maintenance treatment.

Vaccination in neuromyelitis optica spectrum disorders: Friend or enemy?

Neuromyelitis optica spectrum disorders (NMOSDs) are uncommon antibody-mediated autoimmune diseases of the central nervous system (CNS), mainly occurring in optic nerves and spinal cord, which can cause visual impairment, paralysis, and occasionally bulbar dysfunction. Such neurological deficits can adversely affect pulmonary functions and increase complicated infection risk. Besides, most NMOSD patients undergo immunosuppressive therapy. All these factors make NMOSD patients the potential high-risk group under the current pandemic of coronavirus disease 2019 (COVID-19). Meanwhile, COVID-19 infection has already been demonstrated as a risk factor for NMOSD relapses. This review discusses the basic immunology of vaccination and common problems, including immunogenicity, safety, and efficacy of vaccination on NMOSD patients. Additionally, we offered vaccination recommendations, health care and treatment advice for NMOSD patients under the background of COVID-19.

The changing landscape of optic neuritis: a narrative review

Optic neuritis (ON) is an inflammatory optic neuropathy that is often a harbinger of central nervous system (CNS) demyelinating disorders. ON is frequently misdiagnosed in the clinical arena, leading to either inappropriate management or diagnostic delays. As a result, patients may fail to achieve optimal recovery. The treatment response to corticosteroids and long term risk of multiple sclerosis was established in the first clinical trials conducted roughly 30 years ago. Spontaneous resolution was observed in the vast majority of patients and intravenous high-dose corticosteroids hastened recovery; half of the patients eventually developed multiple sclerosis. Over the ensuing decades, the number of inflammatory conditions associated with ON has significantly expanded exposing substantial variability in the prognosis, treatment, and management of ON patients. ON subtypes can frequently be distinguished by distinct clinical, serological, and radiological profiles allowing expedited and specialized treatment. Guided by an increased understanding of the immunopathology underlying optic nerve and associated CNS injuries, novel disease management strategies are emerging to minimize vision loss, improve long-term surveillance strategies, and minimize CNS injury and disability. Knowledge regarding the clinical signs and symptoms of different ON subtypes is essential to guide acute therapy, prognosticate recovery, accurately identify underlying CNS inflammatory disorders, and facilitate study design for the next generation of clinical and translational trials.

Pediatric Neuromyelitis Optica Spectrum Disorder: Case Series and Literature Review

Neuromyelitis Optica Spectrum Disorder (NMOSD) is a central nervous system (CNS) inflammatory demyelinating disease characterized by recurrent inflammatory events that primarily involve optic nerves and the spinal cord, but also affect other regions of the CNS, including hypothalamus, area postrema and periaqueductal gray matter. The aquaporin-4 antibody (AQP4-IgG) is specific for NMOSD. Recently, myelin oligodendrocyte glycoprotein antibodies (MOG-IgG) have been found in a group of AQP4-IgG negative patients. NMOSD is rare among children and adolescents, but early diagnosis is important to start adequate therapy. In this report, we present cases of seven pediatric patients with NMOSD and we review the clinical and neuroimaging characteristics, diagnosis, and treatment of NMOSD in children.

Relapse activity in the chronic phase of anti-myelin-oligodendrocyte glycoprotein antibody-associated disease

Objective

The patterns of relapse and relapse-prevention strategies for anti-myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) are not completely investigated. We compared the patterns of relapse in later stages of MOGAD with those of anti-aquaporin-4 antibody (AQP4-Ab)-positive neuromyelitis optica spectrum disorder (NMOSD).

Methods

In this observational, comparative cohort study, 66 patients with MOGAD and 90 with AQP4-Ab-positive NMOSD were enrolled. We compared the patterns of relapse and annualized relapse rates (ARRs) in the first 10 years from disease onset, stratified by relapse-prevention treatments.

Results

Approximately 50% of the patients with MOGAD experienced relapses in the first 10 years. Among those not undergoing relapse-prevention treatments, ARRs in the first 5 years were slightly lower in MOGAD patients than in AQP4-Ab-positive NMOSD patients (MOGAD vs. AQP4-Ab NMOSD: 0.19 vs. 0.30; p = 0.0753). After 5 years, the ARR decreased in MOGAD patients (MOGAD vs. AQP4-Ab NMOSD: 0.05 vs. 0.34; p = 0.0001), with a 72% reduction from the first 5 years (p = 0.0090). Eight (61.5%) of the 13 MOGAD patients with more than 10-year follow-up from disease onset showed relapse 10 years after onset. Clustering in the timing and phenotype of attacks was observed in both disease patients. The effectiveness of long-term low-dose oral PSL for relapse prevention in patients with MOGAD has not been determined.

Conclusions

The relapse risk in patients with MOGAD is generally lower than that in patients with AQP4-Ab-positive NMOSD, especially 5 years after onset. Meanwhile, relapses later than 10 years from onset are not rare in both diseases.

The costs of care from a US claims database in patients with neuromyelitis optica spectrum disorder

BACKGROUND

Neuromyelitis optica spectrum disorder (NMOSD) is a rare autoimmune disease of the central nervous system that often leads to severe disability. Patients with highly active NMOSD have approximately a 10-times higher hospital inpatient admission rate compared with patients without NMOSD. Accurate assessments of the impact of NMOSD treatments on the burdens of illness require quantitative metrics of these burdens, including costs of care.

METHODS

This study evaluated claims data from the IBM MarketScan Commercial and Medicare Supplemental Databases between 2014 and 2018. Patients were included based on inpatient or outpatient claims meeting criteria defined for NMOSD. Non-NMOSD controls were matched 5:1 to patients with NMOSD. Total costs of healthcare services in consumer price index-adjusted 2019 US dollars during the 1-year postindex follow-up period were calculated for patients and controls.

RESULTS

Patients with NMOSD required more healthcare services and incurred significantly greater costs for inpatient hospitalizations (annual mean [SD] cost: $29,054 [$144,872] vs controls $1521 [$10,759]), outpatient services ($24,881 [$35,463] vs $4761 [$26,447]), and emergency department (ED) visits ($2400 [$7771] vs $408 [$2579]). Almost 12% of patients with NMOSD were further burdened with plasma exchange or intravenous immunoglobulin G treatments, costing an annual median (interquartile range) of $1684 ($566-$3817) and $24,353 ($5425-$42,975), respectively.

CONCLUSIONS

Compared with controls, patients with NMOSD had significantly higher costs associated with hospitalizations, ED visits, and prescriptions. These results highlight the considerable economic burden of NMOSD, which may be favorably impacted by disease-modifying therapies that are regulatory-approved to be safe and effective.

Rehabilitation and pharmacotherapy of neuromyelitis optica spectrum disorder: A case report

BACKGROUND

Neuromyelitis optica spectrum disorder (NMOSD) is a demyelinating autoimmune disease that affects the central nervous system. It typically manifests as optic neuritis or extensive longitudinal myelitis, with or without the presence of anti-aquaporin protein 4 autoantibodies (immunoglobulin G).

CASE SUMMARY

We report the case of a 45-year-old woman with a history of Sjogren's syndrome who was diagnosed with NMOSD accompanied by spinal cord injury and left calf intermuscular vein thrombosis. The patient received hormone shock and gamma globulin therapy in the acute phase and standard rehabilitation treatment during convalescence. Upon discharge, the patient was able to control urination and defecation, stand independently, and walk short distances with the aid of a walker.

CONCLUSION

This case suggests that pharmacotherapy and standard rehabilitation treatment can improve the prognosis of NMSOD patients.

Immune-Mediated Myelopathies: A Review of Etiologies, Diagnostic Approach, and Therapeutic Management

Myelopathy is a broad term used to describe a heterogeneous group of disorders that affects the spinal cord; the focus of this article will be a subgroup of these disorders with an autoimmune and inflammatory-based pathology. Symptoms typically develop over hours or days and then worsen over a matter of days to weeks, but sometimes can have a more insidious or subacute presentation, which can make the diagnosis more puzzling. Despite relatively low incidence rates, almost a third of affected patients are left with severely disabling symptoms. Prompt recognition of the underlying etiology is essential so that a specific targeted therapy can be implemented for optimal outcomes. The authors discuss a systematic approach to immune-mediated myelopathies, with a focus on the unique characteristics of each that may aid in diagnosis.

Targeting interleukin-6 to treat neuromyelitis optica spectrum disorders: Implications from immunology, the FcRn pathway and clinical experience

Neuromyelitis optica spectrum disorder (NMOSD) is a rare disease of the central nervous system (CNS) that is associated with poor outcomes for patients. Until recently, when complement inhibitors were approved, there was no approved therapy. Most recently, clinical trials of interleukin-6 (IL-6) blockade showed a therapeutic benefit for NMOSD. In this review, we introduce the immunological basis of IL-6 blockade in NMOSD and summarize current knowledge about the clinical use of the IL-6 receptor inhibitors tocilizumab and satralizumab. The aim of extending the half-life of monoclonal antibodies (mAbs) has been actualized by successful clinical translation for Satralizumab, achieved via the neonatal Fc receptor (FcRn) pathway. The basic principles of FcRn are highlighted in this review together with the potential therapeutic benefits of this emerging technology.

Recent advances in the treatment of neuromyelitis optica spectrum disorders

PURPOSE OF REVIEW

This review examines recently published randomized placebo-controlled trials for the treatment of neuromyelitis optica spectrum disorders (NMOSD).

RECENT FINDINGS

Until recently, treatments for NMOSD were used-off label and had not been subjected to randomized placebo-controlled trials. Increased understanding of the pathophysiology of NMOSD, particularly aquaporin-4-IgG seropositive NMOSD, lead to the investigation of eculizumab, inebilizumab, and satralizumab for maintenance therapy. Eculizumab inhibits the cleavage of the terminal complement protein C5, inebilizumab depletes immune cells of B-lymphocyte lineage, and satralizumab inhibits interleukin-6 receptors. International, phase 3, randomized, placebo-controlled trials have demonstrated that each of these therapies reduces the risk of NMOSD relapse. In some cases, the studied therapies were administered in conjunction with other immunosuppressants. Each therapy has important safety considerations, notably risk of meningococcal infection with eculizumab and risks of infection and hypogammaglobulinemia with inebilizumab. Reviewing trial design highlights future areas of inquiry for the treatment of NMOSD.

SUMMARY

Eculizumab, inebilizumab, and satralizumab are effective maintenance therapies approved for the treatment of AQP-4 seropositive NMOSD.

Neuromyelitis Optica Spectrum Disorder Treatment-Current and Future Prospects

Neuromyelitis optica (NMO) is an immune-mediated demyelinative disorder of the central nervous system affecting mainly the optical nerves and the spinal cord. The recurrent course of the disease, with exacerbations and incomplete remissions, causes accumulating disability, which has a profound impact upon patients’ quality of life. The discovery of antibodies against aquaporin 4 (AQP4) and their leading role in NMO etiology and the formulation of diagnostic criteria have improved appropriate recognition of the disease. In recent years, there has been rapid progress in understanding the background of NMO, leading to an increasing range of treatment options. On the basis of a review of the relevant literature, the authors present currently available therapeutic strategies for NMO as well as ongoing research in this field, with reference to key points of immune-mediated processes involved in the background of the disease.

Benefits of eculizumab in AQP4+ neuromyelitis optica spectrum disorder: Subgroup analyses of the randomized controlled phase 3 PREVENT trial

BACKGROUND

Antibodies to the aquaporin-4 (AQP4) water channel in neuromyelitis optica spectrum disorder (NMOSD) are reported to trigger the complement cascade, which is implicated in astrocyte damage and subsequent neuronal injury. The PREVENT study demonstrated that the terminal complement inhibitor eculizumab reduces adjudicated relapse risk in patients with anti-AQP4 immunoglobulin G-positive (AQP4+) NMOSD. The objective of this analysis was to evaluate the efficacy of eculizumab in reducing relapse risk and its safety in AQP4+ NMOSD across clinically relevant subgroups in PREVENT.

METHODS

In the randomized, double-blind, time-to-event, phase 3 PREVENT trial, 143 adults received eculizumab (maintenance dose, 1200 mg/2 weeks) or placebo (2:1), with stable-dose concomitant immunosuppressive therapy (IST) permitted (except rituximab and mitoxantrone). Post hoc analyses of relapses and adverse events were performed for prespecified and post hoc subgroups based on concomitant IST and prior rituximab use, demographic and disease characteristics, and autoimmune comorbidity.

RESULTS

The significant reduction in relapse risk observed for eculizumab versus placebo in the overall PREVENT population was consistently maintained across subgroups based on concomitant IST and previous rituximab use, age, sex, region, race, time since clinical onset of NMOSD, historical annualized relapse rate, baseline Expanded Disability Status Scale score, and history of another autoimmune disorder. The serious infection rate was lower with eculizumab than placebo regardless of rituximab use in the previous year, concomitant IST use, or history of another autoimmune disorder.

CONCLUSION

Across a wide range of clinically relevant AQP4+ NMOSD patient subgroups in PREVENT, eculizumab therapy was consistently effective versus placebo in reducing relapse risk, with no apparent increase in serious infection rate.

TRIAL REGISTRATION

NCT01892345 (ClinicalTrials.gov).

Neuromyelitis optica spectrum disorders

The disease concept of Neuromyelitis Optica Spectrum Disorders(NMOSD) has undergone a significant change over the last two decades including the detection of Myelin Oligodendrocyte Glycoprotein(MOG) antibody in patients who are seronegative for aquaporin-4 antibody. Aquaporin-4 antibody positive NMOSD is now regarded as an immune astrocytopathy. Conversely, MOG antibody associated disease is known to target myelin rather than astrocytes, leading to an NMOSD syndrome with distinct clinical and radiological features. Incorporation of clinical features like area postrema syndrome, brainstem syndrome, diencephalic syndrome and cortical manifestations as core clinical characteristics into the revised diagnostic criteria has widened the clinical spectrum of NMOSD. With the development of these criteria, it is possible to make the diagnosis at an earlier stage so that effective immunosuppression can be instituted promptly for a better long-term prognosis. Newer therapeutic agents have been introduced for aquaporin-4 seropositive NMOSD disease; however, challenges remain in treating seronegative disease because of limited treatment options.

Efficacy and safety of mycophenolate mofetil therapy in neuromyelitis optica spectrum disorders: a systematic review and meta-analysis

Mycophenolate mofetil (MMF) is an immunosuppressive agent (IS) which is widely prescribed in neuromyelitis optica spectrum disorder (NMOSD) patients. We aim to assess the efficacy and safety of MMF in controlling relapse and disease severity. Eligible studies obtained from the EMBASE and Ovid MEDLINE databases were studies of NMOSD patients treated with MMF, which reported treatment outcomes as Annualized Relapse Rate (ARR) or Expanded Disability Status Scale (EDSS) before and after treatment. Fifteen studies included 1047 patients, of whom 915 (87.4%) were aquaporin-4 immunoglobulin seropositive. The total number of patients that received MMF was 799. A meta-analysis on ARR was conducted in 200 patients from 4 studies and on EDSS in 158 patients from 3 studies. The result showed a significant improvement with a mean reduction of 1.13 [95% confidence interval (CI) 0.60-1.65] in ARR, and a mean reduction of 0.85 (95% CI 0.36-1.34) in EDSS after MMF therapy. Adverse events occurred in 106 (17.8%) of 594 patients during MMF therapy. This systematic review and meta-analysis showed that using MMF as a preventive therapy in NMOSD patients can significantly reduce relapse rates and improve disease severity with acceptable tolerability.

Potential of B-cell-targeting therapy in overcoming multidrug resistance and tissue invasiveness associated with P-glycoprotein expressing-B cell compartments

Rheumatoid arthritis (RA) is a systemic autoimmune mediated inflammatory disease characterized by progressive joint damage and extra-articular organ manifestations. Among the effector pathways and cells involved in the development of RA, activated B cells play a pivotal role in the pathological process of RA. P-glycoprotein (P-gp), a member of ATP-binding cassette transporters, is induced on the cell membrane by certain stimuli. P-gp transports various drugs from the cytoplasm to the cell exterior, resulting in the development of drug resistance. P-gp expression on B cells appears in patients with RA as the disease activity increases, and treatment of these patients' results in modification of over-expression of P-gp on activated B cells. Evidence suggests that P-gp expressing-activated B cells play important roles in the pathogenesis and treatment resistance in RA through the efflux of intracellular drugs and progression of infiltration in inflammatory lesions. Therapies designed to target activated B cells might overcome refractory RA. Identification of the subsets of peripheral activated B cells that express P-gp in RA patients might help the selection of suitable treatment strategy.

Neuromyelitis optica spectrum disorder in China: Quality of life and medical care experience

BACKGROUND

Neuromyelitis optica spectrum disorder (NMOSD) is considered to be the most common subset of CNS inflammatory demyelinating diseases in China. We aimed to systematically evaluate the impact of NMOSD on Chinese patients' quality of life (QoL), medical care experience, family wellness and social life.

METHODS

A cross-sectional survey was performed involving 210 mostly AQP4-IgG-positive NMOSD patients from 25 provinces across China. An established survey instrument specific for NMOSD developed by The Guthy-Jackson Charitable Foundation and the Multiple Sclerosis Quality of Life-54 scale were implemented. Pearson or Spearman Correlation analysis was performed to define the significant determinants of QoL.

RESULTS

More than 70% of the participants carried an initial diagnosis other than NMOSD, most of the patients were initially diagnosed with idiopathic optic neuritis (43.6%), multiple sclerosis (19.5%), gastrointestinal disorders (11.0%) and depression (10.0%). The average time elapsed between the first symptoms and accurate NMOSD diagnosis was 2.4 ± 4.9 years. Sixty-one percent of the participants reported NMOSD imposing a great negative impact on their life quality. NMOSD worsened both physical and emotional health (Short Form-36 physical health score: 37.9 ± 43.7, emotional health score: 44.8 ± 44.3). Visual impairment, pain, and bowel and bladder dysfunction were the greatest negative physical determinants of overall QoL. Worsened physical health was associated with diminished emotional health (r = 0.71, p < 0.001), and also with an interference in the ability to work (r = 0.41, p < 0.001). Only a small portion (3.3%) of the patients exhibited psychological resilience (with poor physical health but very robust emotional health). NMOSD significantly influenced the decision to have children in the study cohort, especially in the younger generation (r = -0.476, p < 0.001). Non-specific oral immunosuppressants were the most common preventive treatments, and only 13.9% received rituximab treatment. More than half (55.7%) of the patients reported dissatisfaction with current treatment options. A large proportion (88.1%) of the participants reported health insurance insufficient to pay all disease-related costs. Both concerns about treatment and about financial burden contributed to diminished QoL.

CONCLUSIONS

This investigation yields novel insights into the physical, emotional, and socioeconomic impact of NMOSD on Chinese patients, which may afford potentially modifiable aspects of personal or clinical care to improve the patients' QoL, as well as serve as baseline data to reflect how future standard treatments will change patients' life quality.

Eculizumab in the treatment of neuromyelitis optica spectrum disorder

Neuromyelitis optica spectrum disorder (NMOSD) is a rare autoimmune disease of the CNS which is distinct from multiple sclerosis and typically presents with a relapsing course of optic neuritis, myelitis and midline brain inflammatory lesions. In at least two-thirds of cases, antibodies against the water channel AQP4 can be found, which lead to an antibody-mediated activation of the complement system with consecutive damage to neuronal structures. Eculizumab, a humanized monoclonal antibody against the terminal complement component 5, was shown to significantly reduce the risk of NMOSD relapse in a Phase III placebo-controlled trial. Based on this, eculizumab (Soliris^®) was the first drug to be formally approved for the treatment of anti-AQP4-antibody positive NMOSD in 2019.

Transverse myelitis as a rare presentation of antiphospholipid-antibody-associated disorders

We report the case of a 35-year-old male patient suffering from a clinical and radiological manifestation of a transverse myelitis associated with antiphospholipid antibodies. After a challenging diagnosis the patient improved substantially due to immunosuppressive treatment. The demyelinating spinal cord lesion and the impressive therapeutic outcome may support the possibility of a direct binding of antiphospholipid antibodies to CNS antigens and consequently leading to a neuroimmunological pathomechanism distinct from the well-known pro-thrombotic effect of antiphospholipid antibodies. In terms of clinical routine diagnostic this case report highlights a rare but notable differential diagnosis of Multiple Sclerosis-like syndromes.

CNS inflammatory demyelinating disorders: MS, NMOSD and MOG antibody associated disease

Although Multiple Sclerosis is the most common central nervous system (CNS) inflammatory demyelinating disorder, other CNS inflammatory disorders should be included as diagnostic considerations. Neuromyelitis Optica Spectrum Disorder (NMOSD) and myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease are less common but share some clinical characteristics, such as optic neuritis and myelitis, which can make a specific diagnosis challenging. However, these disorders have distinctive and generally different clinical phenotypes, prognosis and management. It is imperative to distinguish each from one another, especially since the treatments (not discussed in this review) can be different. The advent of reliable testing for anti-aquaporin-4 for NMOSD and anti-MOG antibodies has helped significantly; however, diagnosis can remain challenging, especially in sero-negative cases. Clinical indicators are important to guide diagnostic work-up. Careful review of the history, neurological exam, imaging, and/or spinal fluid results are essential to making an accurate diagnosis. In this review, we will examine the clinical presentation, diagnosis, and natural history of these inflammatory CNS disorders.