Long-term efficacy, tolerability and retention rate of azathioprine in 103 aquaporin-4 antibody-positive neuromyelitis optica spectrum disorder patients: a multicentre retrospective observational study from the UK

Disease characteristics of NMOSD and their relationship with disease burden: Observations from a large single-center cohort

OBJECTIVE

To assess the demographic, clinical, and outcome data in patients with NMOSD across a single-center adult cohort and find out associations, if any, with the disease burden.

BACKGROUND

Neuromyelitis Optica spectrum disorder is an autoimmune condition with unpredictable course and relapses. The clinical and economic burden of NMOSD has been studied less.

DESIGN/METHODS

A retrospective analysis of patients diagnosed with NMOSD according to 2015 criteria at the UT Health Houston (UTH) system from 2010 to 2024 was done.

RESULTS

Of the 68 patients, aged 40.03 yrs. (SD = 14.05), 56 (82.35 %) were females, and 17 (25.75 %) had a median household income below 2 times the poverty threshold. 51 (76.11 %) had positive aquaporin4 antibodies, 39 had optic neuritis (57.35 %), and 29 (42.63 %) had myelitis. We classified total relapses into less than 3 vs more than 3, cumulative days of hospitalization into less than 5 vs more than 5, and readmission frequency as less than 1 vs more than 1 per year. The majority of cases had less than 3 relapses (SN = 38 vs 11, MN = 22 vs 6, p > .05), less than 5 days of cumulative hospitalizations (SN = 29 vs 6, MN = 15 vs 5, p > .05), and less than 1 readmissions in a year (SN 15 vs 5, p > .05, MN = 14 vs 10, p > .05).

CONCLUSION

The severity of the disease can be attributed to the major clinical criteria at the time of diagnosis. This can be helpful to identify cases that may have a higher disease burden to the patient and the hospital. Larger studies are needed to confirm the same.

Case report: Satralizumab as an adjunctive therapy for AQP-4 antibody and MOG antibody dual-negative optic neuritis in a third-trimester pregnancy case

The treatment of demyelinating optic neuritis (DON) in pregnant patients is challenging, especially when there is poor or no response to intravenous methylprednisolone pulse (IVMP) therapy or adjunctive treatments such as intravenous immunoglobulin (IVIG) therapy. We herein report a case of a 28-year-old pregnant woman who experienced sequential severe vision loss in both eyes. She presented to a local hospital with the main complaint of sudden, painless vision loss in the left eye and was diagnosed with DON in the left eye. However, she did not receive orbital MRI or IVMP therapy due to safety concerns. Upon admission to our hospital, her visual acuity was 20/30 in the right eye and there was no light perception in the left eye. Her right eye vision deteriorated rapidly, declining to 20/1,000 one day after the admission. The ophthalmic examination revealed a normal anterior segment and a swollen optic disk in the right eye and a dilated pupil with a relative afferent pupillary defect and a swollen optic disk in the left eye. The serological tests for common pathogens, including the aquaporin-4 antibody (AQP-4 Ab), myelin oligodendrocyte glycoprotein antibody (MOG-Ab), and other common autoantibodies, were all negative. The patient was clinically diagnosed with DON in both eyes and received 7 days of IVMP therapy and 4 days of IVIG therapy, but showed no visual improvement. A three-dose regimen of satralizumab 120 mg was then administered subcutaneously during the acute stage of DON, in combination with a slowly tapered oral methylprednisolone regimen. Moreover, 2 months after the first injection of satralizumab, the patient naturally gave birth to a healthy female infant weighing 2,305 g at 36 weeks and 1 day of gestation. Her visual acuity improved to 20/500 in both eyes and slightly increased to 20/320 in both eyes 2 months later. Her visual acuity remained stable during subsequent follow-up visits. The infant was fed formula milk powder and developed normally. No systemic or ocular side effects related to satralizumab therapy were observed in the patient or her fetus during the 9-month follow-up. Our findings in this case suggest that satralizumab may be a safe and efficient adjunctive therapy for pregnant patients with DON who poorly respond to IVMP and IVIG therapy, even in cases of dual-negative AQP-4 Ab and MOG-Ab.

Moving towards a new era for the treatment of neuromyelitis optica spectrum disorders

Neuromyelitis optica spectrum disorders (NMOSD) include a rare group of autoimmune conditions that primarily affect the central nervous system. They are characterized by inflammation and damage to the optic nerves, brain and spinal cord, leading to severe vision impairment, locomotor disability and sphynteric disturbances. In the majority of cases, NMOSD arises due to specific serum immunoglobulin G (IgG) autoantibodies targeting aquaporin 4 (AQP4-IgG), which is the most prevalent water-channel protein of the central nervous system. Early diagnosis and treatment are crucial to manage symptoms and prevent long-term disability in NMOSD patients. NMOSD were previously associated with a poor prognosis. However, recently, a number of randomized controlled trials have demonstrated that biological therapies acting on key elements of NMOSD pathogenesis, such as B cells, interleukin-6 (IL-6) pathway, and complement, have impressive efficacy in preventing the occurrence of clinical relapses. The approval of the initial drugs marks a revolutionary advancement in the treatment of NMOSD patients, significantly transforming therapeutic options and positively impacting their prognosis. In this review, we will provide an updated overview of the key immunopathological, clinical, laboratory, and neuroimaging aspects of NMOSD. Additionally, we will critically examine the latest advancements in NMOSD treatment approaches. Lastly, we will discuss key aspects regarding optimization of treatment strategies and their monitoring.

Are monoclonals the only panacea for treatment of aquaporin-4 positive NMOSD? Experience from a low-&middle-income (LMIC) region

OBJECTIVE

A plethora of monoclonals have ushered up for NMOSD treatment. However, their limited availability and cost concerns poses a challenge for usage in developing nations. We compared relapse rates and disabilities among aquaporin-4 positive(AQP4+ve) patients on conventional immunosuppressants and rituximab in a tertiary referral center in southern India.

METHODS

This was a chart review of AQP4+ve patients registered under national demyelination registry maintained at institute. AQP4+ve patients were included if they were on azathioprine, MMF, methotrexate for six months; cyclophosphamide for three months and rituximab for one month.

RESULTS

207 records were screened, 154 fulfilled inclusion criteria. Drugs used were azathioprine (70), MMF (34) and rituximab (33). All three drugs were non-inferior to each other in terms of ARR reduction. Median EDSS at last follow-up was significantly lower for azathioprine(2;IQR:0-5) and rituximab(2;IQR:0.5-5) than MMF(3.5;IQR:2-5.6), however azathioprine was associated with highest switch rate(34.3%) and was the only drug which required change because of intolerance. Failure rate was least for rituximab(27.3%).Patients on azathioprine and MMF required higher mean duration of concurrent steroids(7.8±7.7 and 4.56±2.17 months respectively) when compared to rituximab(2.77±1.38) and had more relapses due to steroid withdrawal.

CONCLUSION

Initial treatment with azathioprine, MMF and rituximab is comparable in terms of ARR reduction. Findings suggest that choice may be guided by adverse event profile of drug, rather than efficacy per se. Concurrent treatment duration with steroids should also guide clinical decision. Switch to second immunomodulation in event of initial failure adds to efficacy benefit, irrespective of the drug chosen.

Treatment of neuromyelitis optica spectrum disorder: revisiting the complement system and other aspects of pathogenesis

Neuromyelitis optica spectrum disorder (NMOSD) represents a rare neuroimmunological disease causing recurrent attacks and accumulation of permanent disability in affected patients. The discovery of the pathogenic IgG‑1 antibody targeting a water channel expressed in astrocytes, aquaporin 4, constitutes a milestone achievement. Subsequently, multiple pathophysiological aspects of this distinct disease entity have been investigated. Demyelinating lesions and axonal damage ensue from autoantibodies targeting an astroglial epitope. This conundrum has been addressed in the current disease model, where activation of the complement system as well as B cells and interleukin 6 (IL-6) emerged as key contributors. It is the aim of this review to address these factors in light of novel treatment compounds which reflect these pathophysiological concepts in aiming for attack prevention, thus reducing disease burden in patients with NMOSD.

Update on the diagnosis and treatment of neuromyelitis optica spectrum disorders (NMOSD) - revised recommendations of the Neuromyelitis Optica Study Group (NEMOS). Part II: Attack therapy and long-term management

This manuscript presents practical recommendations for managing acute attacks and implementing preventive immunotherapies for neuromyelitis optica spectrum disorders (NMOSD), a rare autoimmune disease that causes severe inflammation in the central nervous system (CNS), primarily affecting the optic nerves, spinal cord, and brainstem. The pillars of NMOSD therapy are attack treatment and attack prevention to minimize the accrual of neurological disability. Aquaporin-4 immunoglobulin G antibodies (AQP4-IgG) are a diagnostic marker of the disease and play a significant role in its pathogenicity. Recent advances in understanding NMOSD have led to the development of new therapies and the completion of randomized controlled trials. Four preventive immunotherapies have now been approved for AQP4-IgG-positive NMOSD in many regions of the world: eculizumab, ravulizumab - most recently-, inebilizumab, and satralizumab. These new drugs may potentially substitute rituximab and classical immunosuppressive therapies, which were as yet the mainstay of treatment for both, AQP4-IgG-positive and -negative NMOSD. Here, the Neuromyelitis Optica Study Group (NEMOS) provides an overview of the current state of knowledge on NMOSD treatments and offers statements and practical recommendations on the therapy management and use of all available immunotherapies for this disease. Unmet needs and AQP4-IgG-negative NMOSD are also discussed. The recommendations were developed using a Delphi-based consensus method among the core author group and at expert discussions at NEMOS meetings.

A comprehensive review of the advances in neuromyelitis optica spectrum disorder

Neuromyelitis optica spectrum disorder (NMOSD) is a rare relapsing neuroinflammatory autoimmune astrocytopathy, with a predilection for the optic nerves and spinal cord. Most cases are characterised by aquaporin-4-antibody positivity and have a relapsing disease course, which is associated with accrual of disability. Although the prognosis in NMOSD has improved markedly over the past few years owing to advances in diagnosis and therapeutics, it remains a severe disease. In this article, we review the evolution of our understanding of NMOSD, its pathogenesis, clinical features, disease course, treatment options and associated symptoms. We also address the gaps in knowledge and areas for future research focus.

Alterations in Aquaporin-4-IgG Serostatus in 986 Patients: A Laboratory-Based Longitudinal Analysis

OBJECTIVE

This study was undertaken to investigate factors associated with aquaporin-4 (AQP4)-IgG serostatus change using a large serological database.

METHODS

This retrospective study utilizes Mayo Clinic Neuroimmunology Laboratory data from 2007 to 2021. We included all patients with ≥2 AQP4-IgG tests (by cell-based assay). The frequency and clinical factors associated with serostatus change were evaluated. Multivariable logistic regression analysis examined whether age, sex, or initial titer was associated with serostatus change.

RESULTS

There were 933 patients who had ≥2 AQP4-IgG tests with an initial positive result. Of those, 830 (89%) remained seropositive and 103 (11%) seroreverted to negative. Median interval to seroreversion was 1.2 years (interquartile range [IQR] = 0.4-3.5). Of those with sustained seropositivity, titers were stable in 92%. Seroreversion was associated with age ≤ 20 years (odds ratio [OR] = 2.25; 95% confidence interval [CI] = 1.09-4.63; p = 0.028) and low initial titer of ≤1:100 (OR = 11.44, 95% CI = 3.17-41.26, p < 0.001), and 5 had clinical attacks despite seroreversion. Among 62 retested after seroreversion, 50% returned to seropositive (median = 224 days, IQR = 160-371). An initial negative AQP4-IgG test occurred in 9,308 patients. Of those, 99% remained seronegative and 53 (0.3%) seroconverted at a median interval of 0.76 years (IQR = 0.37-1.68).

INTERPRETATION

AQP4-IgG seropositivity usually persists over time with little change in titer. Seroreversion to negative is uncommon (11%) and associated with lower titers and younger age. Seroreversion was often transient, and attacks occasionally occurred despite prior seroreversion, suggesting it may not reliably reflect disease activity. Seroconversion to positive is rare (<1%), limiting the utility of repeat testing in seronegative patients unless clinical suspicion is high. ANN NEUROL 2023;94:727-735.

A Clinical Approach to Existing and Emerging Therapeutics in Neuromyelitis Optica Spectrum Disorder

PURPOSE OF REVIEW

Neuromyelitis optica spectrum disorder (NMOSD) is a rare but highly disabling disease of the central nervous system. Unlike multiple sclerosis, disability in NMOSD occurs secondary to relapses that, not uncommonly, lead to blindness, paralysis, and death. Recently, newer, targeted immunotherapies have been trialed and are now in the treatment arsenal. We have endeavoured to evaluate the current state of NMOSD therapeutics.

RECENT FINDINGS

This review provides a pragmatic evaluation of recent clinical trials and post-marketing data for rituximab, inebilizumab, satralizumab, eculizumab, and ravalizumab, contrasted to older agents. We also review contemporary issues such as treatment in the context of SARS-CoV2 infection and pregnancy. There has been a dramatic shift in NMOSD morbidity and mortality with earlier and improved disease recognition, diagnostic accuracy, and the advent of more effective, targeted therapies. Choosing a maintenance therapy remains nuanced depending on patient factors and accessibility. With over 100 putative agents in trials, disease-free survival is now a realistic goal for NMOSD patients.

Role of serostatus in pediatric neuromyelitis optica spectrum disorders: A nationwide multicentric study

BACKGROUND

Neuromyelitis optica spectrum disorders (NMOSD) are immune-mediated inflammatory disorders of the central nervous system (CNS) mostly presenting as optic neuritis and acute myelitis. NMOSD can be associated with seropositivity for aquaporin 4 antibody (AQP4 IgG), myelin oligodendrocyte glycoprotein antibody (MOG IgG), or can be seronegative for both. In this study, we retrospectively examined our seropositive and seronegative pediatric NMOSD patients.

METHOD

Data were collected from all participating centres nationwide. Patients diagnosed with NMOSD were divided into three subgroups according to serology: AQP4 IgG NMOSD, MOG IgG NMOSD, and double seronegative (DN) NMOSD. Patients with at least six months of follow-up were compared statistically.

RESULTS

The study included 45 patients, 29 female and 16 male (ratio:1.8), mean age 15.16 ± 4.93 (range 5.5-27) years. Age at onset, clinical manifestations, and cerebrospinal fluid findings were similar between AQP4 IgG NMOSD (n = 17), MOG IgG NMOSD (n = 10), and DN NMOSD (n = 18) groups. A polyphasic course was more frequent in the AQP4 IgG and MOG IgG NMOSD groups than DN NMOSD (p = 0.007). The annualized relapse rate and rate of disability were similar between groups. Most common types of disability were related to optic pathway and spinal cord involvement. Rituximab in AQP4 IgG NMOSD, intravenous immunoglobulin in MOG IgG NMOSD, and azathioprine in DN NMOSD were usually preferred for maintenance treatment.

CONCLUSION

In our series with a considerable number of double seronegatives, the three major serological groups of NMOSD were indistinguishable based on clinical and laboratory findings at initial presentation. Their outcome is similar in terms of disability, but seropositive patients should be more closely followed-up for relapses.

Systematic Review of Treatment Options and Therapeutic Responses for Lesions of the Sella and Orbit: Evidence-Based Recommendations

OBJECTIVE

Inflammatory pathologies of the sella and orbit are rare but require prompt diagnosis to initiate effective treatment. Because uniform recommendations for treatment are currently lacking, we performed an evidence-based review to identify recommendations.

METHODS

We performed a literature search of the PubMed, Embase, and Web of Science databases to identify papers evaluating treatment of inflammatory pathologies of the sella and orbit. We used PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines to define recommendations, specifically examining aggregated sample sizes, disease-specific patient follow-up, and clinical trials focused on inflammatory diseases of the sella and orbit.

RESULTS

A total of 169 studies were included and organized by disease pathology. Treatments for various pathologies were recorded. Treatment options included surgery, radiation, steroids, targeted treatments, immunomodulators, intravenous immune globulin, and plasmapheresis. Steroids were the most often employed treatment, second-line management options and timing varied. Pathological diagnosis was highly associated with treatment used. Most evidence were level 3 without available control groups, except for 13 trials in neuromyelitis optica with level 1 or 2 evidence.

CONCLUSIONS

This is the first evidence-based review to provide recommendations on specific treatments for pathologies of the orbit and sella. The reported data may be useful to help guide randomized clinical trials and provide resource for clinical management decisions based on the available evidence.

Different monoclonal antibodies and immunosuppressants administration in patients with neuromyelitis optica spectrum disorder: a Bayesian network meta-analysis

BACKGROUND

A variety of novel monoclonal antibodies and immunosuppressant have been proved effective in treating Neuromyelitis Optica Spectrum Disorder (NMOSD). This network meta-analysis compared and ranked the efficacy and tolerability of currently used monoclonal antibodies and immunosuppressive agents in NMOSD.

METHODS

Electronic database including PubMed, Embase and Cochrane Library were searched for relevant studies evaluating monoclonal antibodies and immunosuppressants in patients with NMOSD. The primary outcome measures were annualized relapse rate (ARR), relapse rate, the Expanded Disability Status Scale (EDSS) score, and total adverse events (AEs).

RESULTS

We identified 25 studies with 2919 patients in our meta-analysis. For the primary outcome, rituximab (RTX) (SUCRA: 0.02) ranked first in reduction ARR with a significant difference compared with azathioprine (AZA) (MD - 0.34, 95% CrI - 0.55 to - 0.12) and mycophenolate mofetil (MMF) (MD -0.38, 95% CrI - 0.63 to - 0.14). Tocilizumab (SUCRA: 0.05) ranked first in relapse rate, which was superior to satralizumab (lnOR - 25.4, 95% CrI - 74.4 to - 2.49) and inebilizumab (lnOR - 24.86, 95% CrI - 73.75 to - 1.93). MMF (SUCRA: 0.27) had the fewest AEs followed by RTX (SUCRA: 0.35), both of which showed a significant difference compared with AZA and corticosteroids (MMF vs AZA: lnOR - 1.58, 95% CrI - 2.48 to - 0.68; MMF vs corticosteroids: lnOR - 1.34, 95% CrI - 2.3 to - 0.37) (RTX vs AZA: lnOR - 1.34, 95% CrI - 0.37 to - 2.3; RTX vs corticosteroids: lnOR - 2.52, 95% CrI - 0.32 to - 4.86). In EDSS score, no statistical difference was found between different interventions.

CONCLUSION

RTX and tocilizumab showed better efficacy than traditional immunosuppressants in reducing relapse. For safety, MMF and RTX had fewer AEs. However, studies with larger sample size on newly developed monoclonal antibodies are warranted in the future.

A comparison of the efficacy of tocilizumab versus azathioprine for neuromyelitis optica spectrum disorder: A study protocol for systematic review and meta-analysis

BACKGROUND

Neuromyelitis optica spectrum disorder (NMOSD) is a chronic inflammatory disease of the nervous system, which is frequently accompanied by a pathological humoral immune response against aquaporin-4 water channel. The most common feature of the disorder is recurrent episodes of longitudinally extensive transverse myelitis and optic neuritis. Frequent relapse leads to the gradual accumulation of neurological dysfunction. Azathioprine (AZA) is an empirical attack -preventive immunotherapies drug to prevent the relapse of NMOSD, and tocilizumab (TCZ) has been also reported reduce the activity of NMOSD. Therefore, we designed this systematic review and meta-analysis to evaluate the efficacy between TCZ and AZA in the treatment of NMOSD patients.

METHODS

This study followed the PRISMA guidelines. We searched the English literature between 2000 and 2022 by using relevant medical subject heading and entry terms in PubMed, MEDLINE, Embase and CENTRAL databases. A meta-analysis of drug efficacy was performed using expanded disability status scale score and annualized relapse rate (ARR) as the primary outcome indicators.

RESULTS

The literature search found a total of 1546 articles about TCZ and AZA in the treatment of NMOSD, 27 of which were included in this study after a series of screening. 930 and 148 patients with NMOSD were enrolled, who had been treated with AZA and TCZ, respectively. The pooled standardized mean difference (SMD) of expanded disability status scale score before and after AZA treated was -0.40 (95%CI: -0.50, -0.30) (I2 = 65.4%, P < .001), before and after TCZ treated was -0.84 (95%CI: -1.08, -0.60) (I2 = 45.6%, P = .076). The SMD of ARR before and after AZA treated was -1.01 (95%CI: -1.12, -0.90) (I2 = 83.4%, P < .001), before and after TCZ treated was -1.27 (95%CI: -1.52, -1.03) (I2 = 52.7%, P = .039). In addition, TCZ reduce ARR more significantly compared with AZA (P = .031).

CONCLUSION

The results of this study showed that the treatment of NMOSD patients with AZA and TCZ are associated with decreased number of relapses and disability improvement as well. In addition, compared with AZA, TCZ more significantly reduce ARR.

A Comparison of Pediatric- and Adult-Onset Aquaporin-4 Immunoglobulin G-Positive Neuromyelitis Optica Spectrum Disorder: A Review of Clinical and Radiographic Characteristics

BACKGROUND

The identification of immunoglobulin G antibodies against the aquaporin-4 channel (AQP-IgG) in the majority of adult patients differentiates neuromyelitis optica as a distinct disease entity. The high specificity of AQP4-IgG for neuromyelitis optica has allowed the identification of seropositive patients with atypical presentations of this disease. Neuromyelitis optica spectrum disorder has been increasingly recognized in children who demonstrate patterns of clinical involvement beyond the traditional boundaries of the optic pathways and spinal cord.

METHODS

This is a single-center, retrospective review comparing demographic, clinical/paraclinical, and laboratory features of children and adults with a serologically confirmed diagnosis of AQP4-IgG-positive neuromyelitis optica spectrum disorder.

RESULTS

Of 151 reviewed patient charts, 12 pediatric-onset and 31 adult-onset patients had AQP4-IgG-positive  neuromyelitis optica spectrum disorder. The mean age of pediatric-onset neuromyelitis optica spectrum disorder was 12 ± 3.58 years with a female predilection (3:1). Pediatric patients showed more frequent involvement of the brainstem (6/12 [50%]); P = .008) and diencephalon (3/12 [25%]; P = .018). A preceding infection was identifiable in only 3 of 12 (25%) pediatric-onset patients. Moreover, disability as calculated on the expanded disability status scale was less severe in pediatric-onset cases compared to adult-onset cases in their most recent assessment (0 [0-9]) vs 6.5 [0-10]; P = .005). Pediatric-onset patients were also more likely to respond to treatment of acute episodes with corticosteroids ± intravenous immunoglobulin and/or plasmapheresis (Clinical Global Impression-Change scale: 2.5 [1-4] vs 4 [1-6], P = .009).

INTERPRETATION

This retrospective study was able to compare and contrast pediatric- and adult-onset neuromyelitis optica spectrum disorder. Relative to their adult counterparts, pediatric-onset neuromyelitis optica spectrum disorder patients were more likely to respond to treatment and less likely to be disabled from their disease at follow-up. Therefore, pediatric-onset disease may represent a less virulent form of neuromyelitis optica spectrum disorder.

Progress in treatment of neuromyelitis optica spectrum disorders (NMOSD): Novel insights into therapeutic possibilities in NMOSD

Neuromyelitis optica spectrum disorder (NMOSD) is a rare autoimmune inflammatory demyelinating disorder of the central nervous system (CNS), which is a severely disabling disorder leading to devastating sequelae or even death. Repeated acute attacks and the presence of aquaporin-4 immunoglobulin G (AQP4-IgG) antibody are the typical characteristics of NMOSD. Recently, the phase III trials of the newly developed biologicals therapies have shown their effectiveness and good tolerance to a certain extent when compared with the traditional therapy with the first- and second-line drugs. However, there is still a lack of large sample, double-blind, randomized, clinical studies to confirm their efficacy, safety, and tolerability. Especially, these drugs have no clear effect on NMOSD patients without AQP4-IgG and refractory patients. Therefore, it is of strong demand to further conduct large sample, double-blind, randomized, clinical trials, and novel therapeutic possibilities in NMOSD are discussed briefly here.

Adverse Events in NMOSD Therapy

Neuromyelitis optica spectrum disorders (NMOSD) are rare neurologic autoimmune diseases that have a poor prognosis if left untreated. For many years, generic oral immunosuppressants and repurposed monoclonal antibodies that target the interleukin-6 pathway or B cells were the mainstays of drug treatment. Recently, these drug treatments have been complemented by new biologics developed and approved specifically for NMOSD. In principle, all of these drugs are effective, but treatment recommendations that take this into account are still pending. Instead, the choice of a drug may depend on other criteria such as drug safety or tolerability. In this review, we summarise current knowledge on the adverse effects of azathioprine, mycophenolate mofetil, rituximab, tocilizumab, eculizumab, satralizumab, and inebilizumab in NMOSD. Infections, cytopenias, and infusion-related reactions are most common, but the data are as heterogeneous as the manifestations are diverse. Nevertheless, knowledge of safety issues may facilitate treatment choices for individual patients.

What's new in neuromyelitis optica spectrum disorder treatment?

Optic neuritis, an optic nerve inflammatory disease presenting with acute unilateral or bilateral visual loss, is one of the core symptoms of neuromyelitis optica spectrum disorder (NMOSD). The diagnosis of NMOSD-related optic neuritis is challenging, and it is mainly based on clinical presentation, optical coherence tomography, magnetic resonance imaging scans, and the status of serum aquaporin-4 antibodies. In the pathogenesis, aquaporin-4 antibodies target astrocytes in the optic nerves, spinal cord and some specific regions of the brain eliciting a devastating autoimmune response. Current pharmacological interventions are directed against various steps within the immunological response, notably the terminal complement system, B-cells, and the pro-inflammatory cytokine Interleukin 6 (IL6). Conventional maintenance therapies were off-label uses of the unspecific immunosuppressants azathioprine and mycophenolate mofetil as well as the CD20 specific antibody rituximab and the IL6 receptor specific antibody tocilizumab. Recently, four phase III clinical trials demonstrated the safety and efficacy of the three novel biologics eculizumab, inebilizumab, and satralizumab. These monoclonal antibodies are directed against the complement system, CD19 B-cells and the IL6 receptor, respectively. All three have been approved for NMOSD in the US and several other countries worldwide and thus provide convincing treatment options.

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.

Evaluation of effect of empirical attack-preventive immunotherapies in neuromyelitis optica spectrum disorders: An update systematic review and meta -analysis

BACKGROUND

Neuromyelitis optica spectrum disorder (NMOSD) is an inflammatory disease of the central nervous system, which mainly involves the optic nerve and spinal cord. Frequent relapse can accumulate the degree of disability. At present, the main treatment options are immunosuppressants and blood purification. The first-line immunosuppressants for NMOSD are mainly rituximab (RTX), mycophenolate mofetil (MMF) and azathioprine (AZA). Therefore, we designed this systematic review and meta-analysis to evaluate the safety and effect of the above three drugs in the treatment of NMOSD patients.

METHODS

The following Medical Subject Heading (MeSH) and related entry terms are used to search English literature in PubMed, MEDLINE and CENTRAL databases, respectively. MeSH include: Neuromyelitis optic and Rituximab or Azathioprine or Mycophenolate Mofetil; entry terms include: NMO Spectrum Disorder, NMO Spectrum Disorders, Neuromyelitis Optica (NMO) Spectrum Disorder, Neuromyelitis Optica Spectrum Disorders, Devic Neuromyelitis Optica, Neuromyelitis Optica, Devic, Devic's Disease, Devic Syndrome, Devic's Neuromyelitis Optica, Neuromyelitis Optica (NMO) Spectrum Disorders, CD20 Antibody, Rituximab CD20 Antibody, Mabthera, IDEC-C2B8 Antibody, GP2013, Rituxan, Mycophenolate Mofetil, Mofetil, Mycophenolate, Mycophenolic Acid, Morpholinoethyl Ester, Cellcept, Mycophenolate Sodium, Myfortic, Mycophenolate Mofetil Hydrochloride, Mofetil Hydrochloride, Mycophenolate, RS 61443, RS-61443, RS61443, azathioprine sodium, azathioprine sulfate (note: literature retrieval operators "AND" "OR" "NOT" are used to link MeSH with Entry Terms.) The literature search found a total of 3058 articles about rituximab, mycophenolate mofetil and azathioprine in the treatment of NMOSD, 63 of which were included in this study after a series of screening.

RESULTS

930,933,732 patients with NMOSD were enrolled, who had been treated with MMF, AZA and RTX, respectively. The pooled standardized mean difference (SMD) of EDSS before and after RTX treated was -0.58 (95%CI: -0.72, -0.44) (I² = 0%, p = 0.477), before and after MMF treated was -0.47 (95%CI: -0.73, -0.21) (I² = 85.6%, p<0.001), before and after AZA treated was -0.41 (95%CI: -0.60, -0.23) (I² = 65.4%, p<0.001). there was no significant difference in the effect of the three drugs on reducing EDSS scores (RTX vs MMF, p = 0.522; RTX vs AZA, p = 0.214; MMF vs AZA, p = 0.732). The pooled standardized mean difference (SMD) of ARR before and after RTX treated was -1.45 (95%CI: -1.72, -1.18) (I² = 72.4%, p<0.001), before and after MMF treated was -1.14 (95%CI: -1.31, -0.97) (I² = 54.5%, p<0.001), before and after AZA treated was -1.11 (95%CI: -1.39, -0.83) (I² = 83.4%, p<0.001). RTX significantly reduced ARR compared with the other two drugs (RTX vs MMF, p = 0.039; RTX vs AZA, p = 0.049; MMF vs AZA, p = 0.436).

CONCLUSION

The results of this systematic review and meta-analysis showed that the treatment of NMOSD patients with RTX, MMF and AZA is associated with decreased number of relapses and disability improvement as well, and there was no significant difference in the effect of the three drugs on reducing EDSS scores, but RTX significantly reduced ARR compared with the other two drugs.

Hope for patients with neuromyelitis optica spectrum disorders - from mechanisms to trials

Neuromyelitis optica spectrum disorder (NMOSD) is a rare inflammatory CNS disease that primarily manifests as relapsing episodes of severe optic neuritis and myelitis. Diagnosis of NMOSD is supported by the detection of IgG autoantibodies that target the aquaporin 4 (AQP4) water channel, which, in the CNS, is an astrocyte-specific protein. AQP4 antibody binding leads to AQP4 internalization, complement-dependent and antibody-dependent cellular cytotoxicity, and water channel dysfunction. Cumulative attack-related injury causes disability in NMOSD, so the prevention of attacks is expected to prevent disability accrual. Until recently, no regulator-approved therapies were available for NMOSD. Traditional immunosuppressant therapies, including mycophenolate mofetil, azathioprine and rituximab, were widely used but their benefits have not been assessed in controlled studies. In 2019 and 2020, five phase II and III randomized placebo-controlled trials of four mechanism-based therapies for NMOSD were published and demonstrated that all four effectively prolonged the time to first relapse. All four drugs were monoclonal antibodies: the complement C5 antibody eculizumab, the IL-6 receptor antibody satralizumab, the B cell-depleting antibody inebilizumab, which targets CD19, and rituximab, which targets CD20. We review the pathophysiology of NMOSD, the rationale for the development of these mechanism-based drugs, the methodology and outcomes of the five trials, and the implications of these findings for the treatment of NMOSD.

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.

[Neuromyelitis Optica Spectrum Disorders - Present Insights and Recent Developments]

The achievements of the last 15 years have essentially shaped the diagnostic methods and therapy of Neuromyelitis optica spectrum disorders (NMOSD): from discovery of aquaporin 4 antibodies and further development of diagnostic criteria the path has led to the approval of eculizumab and satralizumab as first disease modifying treatments in Europe. This article should give an overview on the present insights and future treatment options.

Efficacy and safety of modified reduced-dose rituximab in Chinese patients with neuromyelitis optica spectrum disorder: A retrospective cohort study

OBJECTIVE

To evaluate the long-term efficacy and safety of a modified reduced-dose rituximab (mRTX) regimen compared with azathioprine (AZA) and mycophenolate mofetil (MMF) in Chinese patients with neuromyelitis optica spectrum disorder (NMOSD).

METHODS

In this retrospective cohort study, 71 patients with NMOSD were treated with AZA (n = 24), MMF (n = 18), or mRTX (n = 29). The primary outcome was initial relapse after first-line immunosuppressant therapy. The annualized relapse rate (ARR), expanded disability status scale (EDSS) score, activities of daily living (ADL) scale score, and treatment-related adverse events were compared between groups.

RESULTS

Significant ARR reductions were observed in the three groups, with relapse-free rates of 37.5%, 72.2%, and 79.3% in the AZA, MMF, and RTX groups, respectively. Compared with AZA, mRTX and MMF significantly reduced the NMOSD relapse risk. Relapse within 1 year before immunosuppressant therapy or ARR before immunosuppressant therapy increased the NMOSD relapse risk. mRTX and MMF were superior to AZA in reducing the EDSS score and increasing the ADL score, but there was no significant difference between the mRTX and MMF groups. Additionally, mRTX-treated patients were less likely to use steroids concurrently than those treated with AZA and MMF. The adverse event rate in the AZA group was relatively higher than that in the MMF and mRTX groups, though no significant difference was noted among the three groups.

CONCLUSIONS

Compared with AZA, mRTX and MMF significantly reduced the NMOSD relapse risk. mRTX-treated patients presented less concomitant steroid use than those treated with AZA and MMF, fewer adverse events, and better tolerance.

Neuromyelitis optica spectrum disorders: from pathophysiology to therapeutic strategies

Neuromyelitis optica (NMO) is a chronic inflammatory autoimmune disease of the central nervous system (CNS) characterized by acute optic neuritis (ON) and transverse myelitis (TM). NMO is caused by a pathogenic serum IgG antibody against the water channel aquoporin 4 (AQP4) in the majority of patients. AQP4-antibody (AQP4-ab) presence is highly specific, and differentiates NMO from multiple sclerosis. It binds to AQP4 channels on astrocytes, triggering activation of the classical complement cascade, causing granulocyte, eosinophil, and lymphocyte infiltration, culminating in injury first to astrocyte, then oligodendrocytes followed by demyelination and neuronal loss. NMO spectrum disorder (NMOSD) has recently been defined and stratified based on AQP4-ab serology status. Most NMOSD patients experience severe relapses leading to permanent neurologic disability, making suppression of relapse frequency and severity, the primary objective in disease management. The most common treatments used for relapses are steroids and plasma exchange.Currently, long-term NMOSD relapse prevention includes off-label use of immunosuppressants, particularly rituximab. In the last 2 years however, three pivotal clinical trials have expanded the spectrum of drugs available for NMOSD patients. Phase III studies have shown significant relapse reduction compared to placebo in AQP4-ab-positive patients treated with satralizumab, an interleukin-6 receptor (IL-6R) inhibitor, inebilizumab, an antibody against CD19⁺ B cells; and eculizumab, an antibody blocking the C5 component of complement. In light of the new evidence on NMOSD pathophysiology and of preliminary results from ongoing trials with new drugs, we present this descriptive review, highlighting promising treatment modalities as well as auspicious preclinical and clinical studies.

Treatment of Neuromyelitis Optica Spectrum Disorders

Neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune central nervous system (CNS) inflammatory disorder that can lead to serious disability and mortality. Females are predominantly affected, including those within the reproductive age. Most patients develop relapsing attacks of optic neuritis; longitudinally extensive transverse myelitis; and encephalitis, especially brainstem encephalitis. The majority of NMOSD patients are seropositive for IgG autoantibodies against the water channel protein aquaporin-4 (AQP4-IgG), reflecting underlying aquaporin-4 autoimmunity. Histological findings of the affected CNS tissues of patients from in-vitro and in-vivo studies support that AQP4-IgG is directly pathogenic in NMOSD. It is believed that the binding of AQP4-IgG to CNS aquaporin-4 (abundantly expressed at the endfoot processes of astrocytes) triggers astrocytopathy and neuroinflammation, resulting in acute attacks. These attacks of neuroinflammation can lead to pathologies, including aquaporin-4 loss, astrocytic activation, injury and loss, glutamate excitotoxicity, microglial activation, neuroinflammation, demyelination, and neuronal injury, via both complement-dependent and complement-independent pathophysiological mechanisms. With the increased understanding of these mechanisms underlying this serious autoimmune astrocytopathy, effective treatments for both active attacks and long-term immunosuppression to prevent relapses in NMOSD are increasingly available based on the evidence from retrospective observational data and prospective clinical trials. Knowledge on the indications and potential side effects of these medications are essential for a clear evaluation of the potential benefits and risks to NMOSD patients in a personalized manner. Special issues such as pregnancy and the coexistence of other autoimmune diseases require additional concern and meticulous care. Future directions include the identification of clinically useful biomarkers for the prediction of relapse and monitoring of the therapeutic response, as well as the development of effective medications with minimal side effects, especially opportunistic infections complicated by long-term immunosuppression.

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

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.

[Treatment of antibody-mediated encephalomyelitis : Strategies for the treatment of neuromyelitis optica spectrum disorder and myelin oligodendrocyte glycoprotein antibody-associated disease]

BACKGROUND

Antibody-mediated encephalomyelitis, such as neuromyelitis optica spectrum disorder (NMOSD), myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), and glial fibrillary acidic protein (GFAP) antibody-associated astrocytopathy belong to a group of newly described autoimmune diseases.

AIM

Presentation of the treatment of antibody-mediated encephalomyelitis with a focus on NMOSD and MOGAD.

METHODS

Selective literature search in PubMed taking the consultation version of the S2k guidelines of the German Society of Neurology (DGN) on the diagnosis and treatment of multiple sclerosis (MS), NMOSD and MOG IgG-associated diseases into account.

RESULTS

Acute relapses are treated with high-dose steroid pulse therapy or apheresis therapy (plasma exchange or immunoadsorption). It is crucial to start treatment as quickly as possible and apheresis therapy can also be used as first-line treatment under certain conditions. For prophylactic immunotherapy, steroids, classical immunosuppressants and monoclonal antibodies with specific mechanisms of action are used. Eculizumab, inebilizumab and satralizumab are the first drugs approved for NMOSD. Symptomatic treatment and neurorehabilitation are important complementary measures.

CONCLUSION

Treatment of antibody-mediated encephalomyelitis differs from treatment of multiple sclerosis and requires specific measures.

Optimal management of neuromyelitis optica spectrum disorder with aquaporin-4 antibody by oral prednisolone maintenance therapy

BACKGROUND

Neuromyelitis optica spectrum disorder (NMOSD) is a relapsing neuroinflammatory disease associated with aquaporin-4 antibody. Since disabilities in patients with NMOSD accumulate with attacks, relapse prevention is crucially important for improving long-term outcomes. Corticosteroids are inexpensive and promising drugs for relapse prevention in NMOSD, but few studies have analysed the efficacy of corticosteroids in NMOSD, especially regarding the appropriate dosing and tapering regimens.

METHODS

A single-center, retrospective analysis of corticosteroid therapy in aquaporin-4 antibody-positive NMOSD patients fulfilling the 2015 international consensus diagnostic criteria was conducted.

RESULTS

Medical records of a total of 89 Japanese patients with aquaporin-4 antibody-positive NMOSD seen at Department of Neurology, Tohoku University Hospital (2000~2016) were reviewed. At the last follow-up, 66% of the patients were treated with prednisolone (PSL) monotherapy, and the percentage of those receiving PSL monotherapy or a combination of PSL and other immunosuppressants increased from 17.5% in 2000 to 94.1% in 2016. On the other hand, annualised relapse rate (ARR) decreased from 0.78 (13 attacks in 200 person-months) in 2000 to 0.07 (5 attacks in 819 person-months) in 2016. Under PSL treatment, the mean ARR significantly decreased, and disabilities stabilized (PSL treatment vs no-medication; ARR: 0.21 vs 0.98, P < 0.01, Expanded Disability Status Scale score change: +0.02 vs +0.89, P < 0.01, observation periods: 60.1 vs 68.2 months, P=0.26). Using Kaplan-Meier curves, the 10-year relapse-free rate was 46.5% with PSL monotherapy and 7.1% with no medication (hazard ratio: 0.069, 95% confidence interval [CI] 0.024-0.199, P < 0.01). Rapid tapering of PSL (10 mg or less in one year and/or 5 mg or less in two years after clinical attacks) was associated with frequent relapses compared to gradual tapering (more than 10 mg in one year and more than 5 mg in two years after clinical attacks) (rapid vs gradual, 36.7% vs 17.7%, odds ratio 2.69, 95% CI 1.12-6.44, P = 0.02). However, even with PSL of 5 mg/day or less, the relapse rate was low after two years of acute treatment (before vs after, 53.8% vs 13.6%, odds ratio 0.12, 95% CI 0.03-0.50, P < 0.01). Nine patients needed additional immunosuppressants due to insufficient relapse prevention by PSL monotherapy. PSL monotherapy was generally well tolerated, but seven patients had severe adverse events, mainly bone fractures (5 with bone fracture, 1 with femoral capital necrosis and 1 with cerebral infarction).

CONCLUSION

Our study suggests that PSL monotherapy is effective to prevent relapses in about half of patients with aquaporin-4 antibody-positive NMOSD if the doses are gradually reduced. Although it is important to have a treatment strategy tailored to each patient, this study provides evidence that PSL monotherapy can be an option for relapse prevention in some patients with NMOSD.

Neuromyelitis optica spectrum disorder and myelin oligodendrocyte glycoprotein IgG associated disorder: A comprehensive neuro-ophthalmic review

Neuromyelitis optica spectrum disorder (NMOSD) is an antibody-mediated inflammatory disease of the central nervous system that involves the optic nerves, spinal cord, and often other specific brain regions such as area postrema of the medulla. NMOSD was formerly classified as a variant of multiple sclerosis (MS), given the similar symptomatology and relapsing course but is now considered to have distinct clinical, paraclinical, immunological and prognostic features. The discovery of aquaporin 4 (AQP4) immunoglobulin G (IgG) has improved the ability to diagnose NMOSD. AQP4-IgG targets the astrocytic AQP4 water channel leading to complement activation and increased blood-brain barrier permeability. Accurate and early diagnosis is crucial as timely treatment may result in mitigation of long-term disability. Myelin oligodendrocyte glycoprotein (MOG)-IgG associated disorder (MOGAD) is a distinct nosologic entity, which has been more recently described. Its clinical spectrum partly overlaps that of seronegative NMOSD and MS. Although it is considered to have fewer relapses and better prognosis than NMOSD, the clinical course and outcome of MOGAD has not been fully characterized.

B Cells and Antibodies as Targets of Therapeutic Intervention in Neuromyelitis Optica Spectrum Disorders

The first description of neuromyelitis optica by Eugène Devic and Fernand Gault dates back to the 19th century, but only the discovery of aquaporin-4 autoantibodies in a major subset of affected patients in 2004 led to a fundamentally revised disease concept: Neuromyelits optica spectrum disorders (NMOSD) are now considered autoantibody-mediated autoimmune diseases, bringing the pivotal pathogenetic role of B cells and plasma cells into focus. Not long ago, there was no approved medication for this deleterious disease and off-label therapies were the only treatment options for affected patients. Within the last years, there has been a tremendous development of novel therapies with diverse treatment strategies: immunosuppression, B cell depletion, complement factor antagonism and interleukin-6 receptor blockage were shown to be effective and promising therapeutic interventions. This has led to the long-expected official approval of eculizumab in 2019 and inebilizumab in 2020. In this article, we review current pathogenetic concepts in NMOSD with a focus on the role of B cells and autoantibodies as major contributors to the propagation of these diseases. Lastly, by highlighting promising experimental and future treatment options, we aim to round up the current state of knowledge on the therapeutic arsenal in NMOSD.

Low-dose tacrolimus in treating neuromyelitis optica spectrum disorder

BACKGROUND

The value of tacrolimus (TAC) in neuromyelitis optica spectrum disorder (NMOSD) has not been fully demonstrated. In this study, we aimed to explore the effectiveness and safety of low-dose TAC in treating NMOSD.

METHODS

Patients with NMOSD taking low-dose TAC were retrospectively collected. We compared the annualized relapse rate (ARR) before and after the initiation of TAC. Cox proportional hazards model was used to identify the risk factors of relapse during TAC treatment with their hazard ratio (HR). The effectiveness and safety of TAC were also compared with a group of patients on mycophenolate mofetil (MMF).

RESULTS

A total of 42 NMOSD patients taking TAC were included, with the administered dose of 1-3mg/d. The ARR (1, 0-3) after the initiation of TAC decreased significantly compared to those before TAC treatment (0, 0-2, p < 0.001). The most common adverse events (AEs) observed included alopecia (23.8%), tremor (16.7%) and elevated blood glucose (11.9%). Multivariate Cox proportional hazards model exhibited that patients with higher baseline ARR (HR: 1.77, 0.76-4.16) and Expanded Disability Status Scale (EDSS) score (HR: 1.79, 1.20-2.68) were at a higher risk for relapse during TAC treatment (p = 0.188 and 0.004, respectively). We did not observe significant difference between TAC-treated and MMF-treated patients regarding the risk of relapse (p = 0.323).

CONCLUSION

Low-dose TAC was an effective and tolerable choice in treating NMOSD.

Safety and efficacy of mycophenolate mofetil in treating neuromyelitis optica spectrum disorders: a protocol for systematic review and meta-analysis

INTRODUCTION

Neuromyelitis optica spectrum disorders (NMOSD) is an inflammatory and heterogeneous astrocyte disorder of the central nervous system with the characteristic of higher incidence in women and Asian people. Most patients with NMOSD have a course of recurrence and remission that is prone to cause paralysis and blindness. Several studies have confirmed the efficacy and promising prospect of mycophenolate mofetil (MMF) in the treatment of NMOSD. Yet its therapeutic effect and safety are controversial. Although there has been two published literature that is relevant to the topic of this study, both of them have certain defects, and they can only provide answers about the efficacy or safety of MMF in the treatment of NMOSD from partial perspectives or conclusions. This research aims to perform a direct and comprehensive systematic review and meta-analysis to evaluate MMF's effectiveness and safety in treating NMOSD.

METHODS AND ANALYSIS

This systematic review will cover all comparative researches, from randomised controlled trials to cohort studies, and case-control study. A relevant literature search will be conducted in PubMed, Web of Science, EMBASE, the Cochrane Library, China National Knowledge Infrastructure, Wanfang Database, China Science and Technology Journal Database and Chinese Biomedical Literature Database from their inception to 31 June 2020. We will also search registers of clinical trials, potential grey literature and abstracts from conferences. There are no limits on language and publication status. The reporting quality and risk of bias will be assessed by two researchers independently. Expanded Disability Status Scales and annualised relapse rate will be evaluated as the primary outcome. The secondary outcomes will consist of the frequency and severity of adverse events, best-corrected visual acuity, relapse-free rate and time to the next attack. A meta-analysis will be performed using RevMan V.5.3 software provided by the Cochrane Collaboration and Stata V.12.0.

ETHICS AND DISSEMINATION

Because the data used for this systematic review will be exclusively extracted from published studies, ethical approval and informed consent of patients will not be required. The systematic review will be published in a peer-reviewed journal, presented at conferences and will be shared on social media platforms.

PROSPERO REGISTRATION NUMBER

CRD42020164179.

Efficacy for the Annual Relapse Rate after the Immunosuppressive Therapy in Patients Associated with Anti-AQP4 or Anti-MOG Antibody-Positive Optic Neuritis

Purpose

Although oral prednisolone is the first-line treatment for preventing recurrent optic neuritis (ON) after the completion of acute-phase treatment, especially anti-aquaporin 4 (AQP4) antibody-positive ON, and anti-myelin oligodendrocyte glycoprotein (MOG) antibody-positive ON, some patients experience relapses. Immunosuppressants could be effective in reducing the recurrence rate for neuromyelitis optica spectrum disorder and MOG antibody-related diseases, but there have been few studies addressing this issue focusing on the changes in ophthalmic parameters. The objective of the study was to analyze the impact of off-label uses of immunosuppressants to reduce recurrent ON.

Design

Retrospective observational study, clinical case series.

Methods

We reviewed the medical charts of 11 cases (22 eyes) who underwent immunosuppressive therapy in Kobe University Hospital and compared the annualized relapse rate (ARR) before and after immunosuppressive therapy. We also evaluated the dosage of prednisolone, complications of immunosuppressants, and other visual functional ophthalmologic parameters.

Results

Eleven cases in total had AQP4 antibody (9 cases) and/or MOG antibody (3 cases). One case was double positive for these antibodies. Nine patients received azathioprine and two received mycophenolate mofetil as an initial immunosuppressive therapy. The median duration of immunosuppressant treatment was 2.8 years. The median ON ARR before immunosuppressive therapy was 0.33, and this decreased significantly to 0 after the therapy (p = 0.02). The dose of prednisolone was reduced from 17.8 ± 7.1 mg/day before to 5.8 ± 2.2 mg/day after immunosuppressive therapy (p < 0.01). Although two patients presented with mild elevation of liver enzymes and nausea, all patients were able to continue taking the immunosuppressants.

Conclusions

Immunosuppressants can potentially decrease relapses and steroid dosage in patients with anti-AQP4 or MOG antibody-positive ON without severe adverse events and the exacerbation of visual acuities.

Neuromyelitis optica

Neuromyelitis optica (NMO; also known as Devic syndrome) is a clinical syndrome characterized by attacks of acute optic neuritis and transverse myelitis. In most patients, NMO is caused by pathogenetic serum IgG autoantibodies to aquaporin 4 (AQP4), the most abundant water-channel protein in the central nervous system. In a subset of patients negative for AQP4-IgG, pathogenetic serum IgG antibodies to myelin oligodendrocyte glycoprotein, an antigen in the outer myelin sheath of central nervous system neurons, are present. Other causes of NMO (such as paraneoplastic disorders and neurosarcoidosis) are rare. NMO was previously associated with a poor prognosis; however, treatment with steroids and plasma exchange for acute attacks and with immunosuppressants (in particular, B cell-depleting agents) for attack prevention has greatly improved the long-term outcomes. Recently, a number of randomized controlled trials have been completed and the first drugs, all therapeutic monoclonal antibodies, have been approved for the treatment of AQP4-IgG-positive NMO and its formes frustes.

Recent progress in maintenance treatment of neuromyelitis optica spectrum disorder

Background

Treatment of neuromyelitis optica spectrum disorder (NMOSD) has so far been based on retrospective case series. The results of six randomized clinical trials including five different monoclonal antibodies targeting four molecules and three distinct pathophysiological pathways have recently been published.

Methods

Literature search on clinical trials and case studies in NMOSD up to July 10. 2020.

Results

We review mechanism of action, efficacy and side effects, and consequences for reproductive health from traditional immunosuppressants and monoclonal antibodies including rituximab, inebilizumab, eculizumab, tocilizumab and satralizumab.

Conclusion

In NMOSD patients with antibodies against aquaporin 4, monoclonal antibodies that deplete B cells (rituximab and inebilizumab) or interfere with interleukin 6 signaling (tocilizumab and satralizumab) or complement activation (eculizumab) have superior efficacy compared to placebo. Tocilizumab and rituximab were also superior to azathioprine in head-to-head studies. Rituximab, tocilizumab and to some extent eculizumab have well-known safety profiles for other inflammatory diseases, and rituximab and azathioprine may be safe during pregnancy.

Efficacy and safety of azathioprine for neuromyelitis optica spectrum disorders: A meta-analysis of real-world studies

OBJECTIVE

This study aimed to perform a meta-analysis of the efficacy and safety of azathioprine (AZA) for neuromyelitis optica spectrum disorders (NMOSD), considering the potential predictive factors related to patient response to AZA in this disease.

METHODS

We performed a systematic online query in PubMed, EMBASE, The Cochrane Library, ClinicalTrials.gov, China National Knowledge Infrastructure, WANFANG DATA, and CQVIP DATA. The available studies on the use of AZA in NMOSD patients were included.

RESULTS

We analyzed a total of 21 studies including 1016 patients. Results demonstrated that AZA significantly decreased annual relapse rate (ARR) by 1.164 (95% confidence intervals (CI), -1.396 to -0.932; p < 0.001). Subgroup analysis showed that AZA significantly decreased ARR in both low-dose group (effect size (ES): -1.545) and moderate-dose group (ES: -2.026). AZA therapy also resulted in a significant reduction of 1.117 (95% CI: -1.668 to -0.566; p < 0.001) in expanded disability status scale (EDSS) score. AZA did not affect EDSS score in the low-dose subgroup (ES: -0.535; p = 0.209) or the moderate-dose subgroup (ES: -0.709; p = 0.064). During AZA therapy, 47% of patients did not experience any relapses (95% CI, 39% to 54%). In addition, 13% of patients developed leukopenia, 11% had elevated liver enzyme levels, 8% experienced nausea or vomiting, 5% developed pancytopenia and 6% died during follow-up.

CONCLUSION

AZA is effective in reducing relapse and improving patients' neurological function. However, liver function monitoring and routine blood monitoring remain necessary. Within the safe upper limit, a higher dose of AZA may be associated with a better efficacy for NMOSD.

Emerging drugs for the treatment of neuromyelitis optica

INTRODUCTION

Evidence-based treatment options for neuromyelitis optica spectrum disorders (NMOSD) patients are beginning to enter the market. Where previously, there was only the exclusive use of empiric and off-label immunosuppressants in this rare and devastating central nervous system autoimmune disease.

AREAS COVERED

In accordance to expanding pathogenetic insights, drugs in phase II and III clinical trials are presented in the context of the current treatment situation for acute attacks and immunopreventative strategies in NMOSD. Some such drugs are the 2019-approved complement inhibitor eculizumab, other compounds in late development include its modified successor ravulizumab, IL-6 receptor antibody satralizumab, CD19 targeting antibody inebilizumab and the TACI-Fc fusion protein telitacicept.

EXPERT OPINION

Moving from broad immunosuppression to tailored treatment strategies, the prospects for efficient NMOSD therapy are positive. For the first time in this disease, class I treatment evidence is available, but long-term data will be necessary to confirm the overall promising study results of the compounds close to approval. While drug development still centers around AQP4 antibody seropositive patients, current and future research requires consideration of possible diverging treatment demands for the smaller group of seronegative patients and patients with presence of MOG antibodies.

Management Strategies of Patients with Neuromyelitis Optica Spectrum Disorder During the COVID-19 Pandemic Era

The ongoing coronavirus (COVID-19) pandemic is a global health emergency of international concern and has affected management plans of many autoimmune disorders. Immunosuppressive and immunomodulatory therapies are pivotal in the management of neuromyelitis optica spectrum disorder (NMOSD), potentially placing patients at an increased risk of contracting infections such as COVID-19. The optimal management strategy of NMOSD during the COVID-19 era remains unclear. Here, however, we examined the evidence of NMOSD disease-modifying therapies (DMTs) use during the present period and highlighted different scenarios including treatment of relapses as well as initiation and maintenance of DMTs in order to optimize care of NMOSD patients in the COVID-19 era.

Safety and efficacy of tocilizumab versus azathioprine in highly relapsing neuromyelitis optica spectrum disorder (TANGO): an open-label, multicentre, randomised, phase 2 trial

BACKGROUND

Azathioprine is used as a first-line treatment to prevent relapses of neuromyelitis optica spectrum disorder (NMOSD). Tocilizumab has been reported to reduce NMOSD disease activity in retrospective case reports. We aimed to compare the safety and efficacy of tocilizumab and azathioprine in patients with highly relapsing NMOSD.

METHODS

We did an open-label, multicentre, randomised, phase 2 trial at six hospitals in China. We recruited adult patients (aged ≥18 years) with highly relapsing NMOSD diagnosed according to 2015 International Panel for Neuromyelitis Optica Diagnosis criteria, who had an Expanded Disability Status Scale (EDSS) score of 7·5 or lower, and had a history of at least two clinical relapses during the previous 12 months or three relapses during the previous 24 months with at least one relapse within the previous 12 months. Patients were randomly assigned (1:1) to intravenous tocilizumab (8 mg/kg every 4 weeks) or oral azathioprine (2-3 mg/kg per day) by an independent statistician using computer-generated randomisation software with permuted blocks of four. The central review committee, EDSS raters, laboratory personnel, and radiologists were masked to the treatment assignment, but investigators and patients were aware of treatment allocation. The minimum planned duration of treatment was 60 weeks following randomisation. The primary outcome was time to first relapse in the full analysis set, which included all randomly assigned patients who received at least one dose of study drug, and the per-protocol population, which included all patients who used azathioprine or tocilizumab as monotherapy. For the analyses of the primary outcome, the patients were prespecified into two subgroups according to concomitant autoimmune disease status. Safety was assessed in the full analysis set. This study is registered with ClinicalTrials.gov, NCT03350633.

FINDINGS

Between Nov 1, 2017, and Aug 3, 2018, we enrolled 118 patients, of whom 59 were randomly assigned to tocilizumab and 59 were randomly assigned to azathioprine. All 118 patients received one dose of study drug and were included in the full analysis set. 108 participants were included in the per-protocol analysis (56 in the tocilizumab group and 52 in the azathioprine group). In the full analysis set, median time to the first relapse was longer in the tocilizumab group than the azathioprine group (78·9 weeks [IQR 58·3-90·6] vs 56·7 [32·9-81·7] weeks; p=0·0026). Eight (14%) of 59 patients in the tocilizumab group and 28 (47%) of 59 patients in the azathioprine group had a relapse at the end of the study (hazard ratio [HR] 0·236 [95% CI 0·107-0·518]; p<0·0001). In the per-protocol analysis, 50 (89%) of 56 patients in the tocilizumab group were relapse-free compared with 29 (56%) of 52 patients in the azathioprine group at the end of the study (HR 0·188 [95% CI 0·076-0·463]; p<0·0001); the median time to first relapse was also longer in the tocilizumab group than the azathioprine group (67·2 weeks [IQR 47·9-77·9] vs 38·0 [23·6-64·9]; p<0·0001). In the prespecified subgroup analysis of the full analysis set stratified by concomitant autoimmune diseases, among patients without concomitant autoimmune diseases, three (9%) of 34 patients in the tocilizumab group and 13 (35%) of 37 patients in the azathioprine group had relapsed by the end of the study. Among patients with concomitant autoimmune diseases, a lower proportion of patients in the tocilizumab group had a relapse than in the azathioprine group (five [20%] of 25 patients vs 15 [68%] of 22 patients; HR 0·192 [95% CI 0·070-0·531]; p=0·0004). 57 (97%) of 59 patients in the tocilizumab group and 56 (95%) of 59 patients in the azathioprine group had adverse events. Treatment-associated adverse events occurred in 36 (61%) of 59 tocilizumab-treated patients and 49 (83%) of 59 azathioprine-treated patients. One death (2%) occurred in the tocilizumab group and one (2%) in the azathioprine group, but neither of the deaths were treatment-related.

INTERPRETATION

Tocilizumab significantly reduced the risk of a subsequent NMOSD relapse compared with azathioprine. Tocilizumab might therefore be another safe and effective treatment to prevent relapses in patients with NMOSD.

FUNDING

Tianjin Medical University, Advanced Innovation Center for Human Brain Protection, National Key Research and Development Program of China, National Science Foundation of China.

Differential Effects of MS Therapeutics on B Cells-Implications for Their Use and Failure in AQP4-Positive NMOSD Patients

B cells are considered major contributors to multiple sclerosis (MS) pathophysiology. While lately approved disease-modifying drugs like ocrelizumab deplete B cells directly, most MS medications were not primarily designed to target B cells. Here, we review the current understanding how approved MS medications affect peripheral B lymphocytes in humans. These highly contrasting effects are of substantial importance when considering these drugs as therapy for neuromyelitis optica spectrum disorders (NMOSD), a frequent differential diagnosis to MS, which is considered being a primarily B cell- and antibody-driven diseases. Data indicates that MS medications, which deplete B cells or induce an anti-inflammatory phenotype of the remaining ones, were effective and safe in aquaporin-4 antibody positive NMOSD. In contrast, drugs such as natalizumab and interferon-β, which lead to activation and accumulation of B cells in the peripheral blood, lack efficacy or even induce catastrophic disease activity in NMOSD. Hence, we conclude that the differential effect of MS drugs on B cells is one potential parameter determining the therapeutic efficacy or failure in antibody-dependent diseases like seropositive NMOSD.

Pediatric NMOSD: A Review and Position Statement on Approach to Work-Up and Diagnosis

Neuromyelitis Optica Spectrum Disorder (NMOSD) is an inflammatory demyelinating disease of the central nervous system (CNS) primarily affecting the optic nerves and spinal cord, but also involving other regions of the CNS including the area postrema, periaqueductal gray matter, and hypothalamus. Knowledge related to pediatric manifestations of NMOSD has grown in recent years, particularly in light of newer information regarding the importance of not only antibodies to aquaporin 4 (AQP4-IgG) but also myelin oligodendrocyte glycoprotein (MOG-IgG) in children manifesting clinically with this syndrome. In this review, we describe the current state of the knowledge related to clinical manifestations, diagnosis, and chronic therapies for children with NMOSD, with emphasis on literature that has been published in the last 5 years. Following the review, we propose recommendations for the assessment/follow up clinical care, and treatment of this population.

Neuroinflammatory and Demyelinating Disorders of Childhood

In this chapter, we will review monophasic and recurrent demyelinating disorders in children. We will first review consensus definitions and provide an approach to the evaluation of children with first episode of acquired demyelinating disorder. We will discuss typical clinical and radiological features of these syndromes. In the second section, we will review features of recurrent demyelinating syndromes in children, focusing on clinical presentation and treatment options.

Treatment in childhood central nervous system demyelinating disorders

The last two decades witnessed significant advances in the treatment of acquired demyelinating disorders: thirteen new agents have been approved for the treatment of multiple sclerosis in adults by the European Medicines Agency and US Food and Drug Administration in the last twenty years. Although the long-term efficacy and safety profiles of some new drugs are still being assessed in paediatric MS, clinicians may have to use them in the management of paediatric onset MS resistant to first-line medications, based on results obtained in adult-onset disease. This review summarizes the current approach to treatment in children with demyelinating syndromes. WHAT THIS PAPER ADDS: Serological markers affect management in paediatric demyelinating diseases. Antibodies against aquaporin-4 and myelin oligodendrocyte glycoprotein should be tested in children with acute demyelinating disease. New therapeutic agents currently in trial for pediatric disease should be used with close follow-up.