Beneficial effects of intravenous immunoglobulin as an add-on therapy to azathioprine for NMO-IgG-seropositive neuromyelitis optica spectrum disorders

Comparison of efficacy of plasma exchange versus intravenous immunoglobulin as an add-on therapy in acute attacks of neuromyelitis optica spectrum disorder

INTRODUCTION

Plasma exchange (PE) is considered a Category II option for the treatment of acute attacks and relapse cases of neuromyelitis optica spectrum disorder (NMOSD). However, neurologists are also considering intravenous immunoglobulins (IVIg) as an add-on therapy for this disorder.

AIMS

The aim of this study is to evaluate the efficacy of PE in acute attacks of NMOSD when compared with IVIg, in terms of improvement in the Expanded disability status scale (EDSS) and activities of daily living (ADL) scale score and levels of anti-Aquaporin P4 (AQP4) antibody in seropositive patients.

METHODS

We enrolled 43 NMOSD patients in two groups: Group 1 (n = 29) received steroids and PE, and Group 2 (n = 14) received steroids with IVIg. The baseline EDSS and ADL scores were recorded and compared with scores at the end of therapy, 4 weeks, and 3 months after. Also, anti-AQP4 antibody was measured at baseline and post-therapy in seropositive patients of both groups.

RESULTS

We observed a significant difference in EDSS (p = 0.00) and ADL score (p = 0.00) at day 10 and 3 months in both groups. However, no significant difference in EDSS, as well as ADL score from baseline (p = 0.83; p = 0.25) to 3 months (p = 0.85; p = 0.19), was observed when delta change of score at 3 months was compared across the two groups (p = 0.39; p = 0.52). We observed improved visual acuity in both groups with mild improvement in findings of magnetic resonance imaging at 3 months. We observed a significant decline in AQP4 antibody concentration (at day 10) in group 1 seropositive patients (p = 0.013) with improved EDSS (p = 0.027) and ADL scores (p = 0.026) of these patients.

CONCLUSIONS

PE should be considered as a choice of an add-on therapy in anti-AQP4 antibody-positive NMOSD patients compared with IVIg as it is more effective in reducing antibody concentrations.

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.

Optic neuritis with potential for poor outcome

The Optic Neuritis Treatment Trial previously reported that corticosteroids accelerated visual recovery in optic neuritis (ON) without improving outcome. This finding related largely to multiple sclerosis (MS), and subsequently neurologists tended to await spontaneous recovery in ON. Since then, non-MS cases of ON have been identified with antibodies to aquaporin-4 (AQP4) or myelin oligodendrocyte glycoprotein (MOG). These disorders can closely mimic multiple sclerosis-associated or idiopathic demyelinating optic neuritis (MS/IDON) initially but risk a worse visual outcome. Scrutinising the clinical features and neuroimaging often enables differentiation between MS/IDON and other causes of ON. Early treatment with high-dose corticosteroids is an important determinant of visual outcome in non-MS/IDON. Prompt use of plasma exchange may also save sight. In this review, we contrast the presentations of myelin oligodendrocyte glycoprotein associated optic neuritis (MOG-ON) and aquaporin 4 associated optic neuritis (AQP4-ON) with MS/IDON and provide an approach to acute management while awaiting results of antibody testing.

Neonatal Fc Receptor-Targeted Therapies in Neurology

Autoantibodies are increasingly recognized for their pathogenic potential in a growing number of neurological diseases. While myasthenia gravis represents the prototypic antibody (Ab)-mediated neurological disease, many more disorders characterized by Abs targeting neuronal or glial antigens have been identified over the past two decades. Depletion of humoral immune components including immunoglobulin G (IgG) through plasma exchange or immunoadsorption is a successful therapeutic strategy in most of these disease conditions. The neonatal Fc receptor (FcRn), primarily expressed by endothelial and myeloid cells, facilitates IgG recycling and extends the half-life of IgG molecules. FcRn blockade prevents binding of endogenous IgG to FcRn, which forces these antibodies into lysosomal degradation, leading to IgG depletion. Enhancing the degradation of endogenous IgG by FcRn-targeted therapies proved to be a powerful therapeutic approach in patients with generalized MG and is currently being tested in clinical trials for several other neurological diseases including autoimmune encephalopathies, neuromyelitis optica spectrum disorders, and inflammatory neuropathies. This review illustrates mechanisms of FcRn-targeted therapies and appraises their potential to treat neurological diseases.

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.

Update on Intravenous Immunoglobulin in Neurology: Modulating Neuro-autoimmunity, Evolving Factors on Efficacy and Dosing and Challenges on Stopping Chronic IVIg Therapy

In the last 25 years, intravenous immunoglobulin (IVIg) has had a major impact in the successful treatment of previously untreatable or poorly controlled autoimmune neurological disorders. Derived from thousands of healthy donors, IVIg contains IgG1 isotypes of idiotypic antibodies that have the potential to bind pathogenic autoantibodies or cross-react with various antigenic peptides, including proteins conserved among the "common cold"-pre-pandemic coronaviruses; as a result, after IVIg infusions, some of the patients' sera may transiently become positive for various neuronal antibodies, even for anti-SARS-CoV-2, necessitating caution in separating antibodies derived from the infused IVIg or acquired humoral immunity. IVIg exerts multiple effects on the immunoregulatory network by variably affecting autoantibodies, complement activation, FcRn saturation, FcγRIIb receptors, cytokines, and inflammatory mediators. Based on randomized controlled trials, IVIg is approved for the treatment of GBS, CIDP, MMN and dermatomyositis; has been effective in, myasthenia gravis exacerbations, and stiff-person syndrome; and exhibits convincing efficacy in autoimmune epilepsy, neuromyelitis, and autoimmune encephalitis. Recent evidence suggests that polymorphisms in the genes encoding FcRn and FcγRIIB may influence the catabolism of infused IgG or its anti-inflammatory effects, impacting on individualized dosing or efficacy. For chronic maintenance therapy, IVIg and subcutaneous IgG are effective in controlled studies only in CIDP and MMN preventing relapses and axonal loss up to 48 weeks; in practice, however, IVIg is continuously used for years in all the aforementioned neurological conditions, like is a "forever necessary therapy" for maintaining stability, generating challenges on when and how to stop it. Because about 35-40% of patients on chronic therapy do not exhibit objective neurological signs of worsening after stopping IVIg but express subjective symptoms of fatigue, pains, spasms, or a feeling of generalized weakness, a conditioning effect combined with fear that discontinuing chronic therapy may destabilize a multi-year stability status is likely. The dilemmas of continuing chronic therapy, the importance of adjusting dosing and scheduling or periodically stopping IVIg to objectively assess necessity, and concerns in accurately interpreting IVIg-dependency are discussed. Finally, the merit of subcutaneous IgG, the ineffectiveness of IVIg in IgG4-neurological autoimmunities, and genetic factors affecting IVIg dosing and efficacy are addressed.

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.

Longitudinally Extensive Transverse Myelitis in a Lupus-Neuromyelitis Optica Overlap

Transverse myelitis is an inflammatory lesion of the spinal cord, occurring in different autoimmune, infectious, and traumatic diseases but is the hallmark of neuromyelitis optica (NMO), a rare neurologic autoimmune disease. Patients with systemic lupus erythematosus (SLE) may develop transverse myelitis as a neuropsychiatric complication of active disease; however, at times, NMO co-exists as an additional primary autoimmune condition in a SLE patient. Correct diagnosis of a SLE-NMO overlap is important not only for the different disease course and prognosis compared with SLE-related LETM, but especially for the emerging and highly specific NMO treatment options, not established for SLE-related LETM-such as anti-aquaporin 4 antibodies, anti-VEGF antibodies, complement modulation, or IVIg.

Management of Idiopathic CNS inflammatory diseases during the COVID-19 pandemic: Perspectives and strategies for continuity of care from a South East Asian Center with limited resources

The Covid-19 pandemic poses a grave health management challenge globally of unprecedented nature. Management of idiopathic Central Nervous system inflammatory disorders (iCNSID) such as Multiple sclerosis, Neuromyelitis optica and its spectrum disorders and related conditions during this pandemic needs to be addressed with affirmative and sustainable strategies in order to prevent disease related risks, medication related complications and possible COVID-19 disease associated effects. Global international iCNSIDs agencies and recent publications are attempting to address this but such guidance is not available in South East Asia. Here we outline prospectively qualitatively and quantitatively novel strategies at a tertiary center in Malaysia catering for neuroimmunological disorders despite modest resources during this pandemic. In this retrospective study with longitudinal follow-up, we describe stratification of patients for face to face versus virtual visits in the absence of formal teleneurology, stratification of patients for treatment according to disease activity, rescheduling, deferring initiation or extending treatment intervals of certain disease modifying therapies(DMT's) or immunosuppressants(IS), especially those producing lymphocyte depletion in MS and the continuation of IS in patients with NMO/NMOSD. Furthermore, we highlight the use off-label treatments such as Intravenous immunoglobulins/rituximab,bridging interferons/Teriflunomide temporarily replacing more potent DMT choices,supply challenges of IS/DMT's and tailoring blood watches and neuroimaging surveillance based on the current health needs to stave off the pandemic and prevent at risk patients with iCNSID/health care workers from possibly being exposed to the COVID-19.