International Consensus Guidance for Management of Myasthenia Gravis: 2020 Update

Eculizumab in thymoma-associated myasthenia gravis: a real-world cohort study

Background

Thymoma-associated myasthenia gravis (TAMG) is a subtype of myasthenia gravis (MG) that is associated with more severe symptoms and a relatively poor prognosis. Eculizumab, an inhibitor to target human C5 component of the complement cascade, is considered a treatment option for refractory generalized MG (gMG).

Objectives

To explore the safety and efficacy of eculizumab in patients with TAMG.

Design

This is an observational multicenter real-world cohort study to assess TAMG who were treated with eculizumab from June 2023 to June 2024.

Data sources and methods

Clinical features associated with thymoma-associated multi-organ autoimmunity (TAMA), Myasthenia Gravis Activities of Daily Living (MG-ADL) score, and the incidence of treatment-emergent adverse events (TEAEs) were prospectively collected.

Results

Overall, 42 patients with gMG were treated with eculizumab at 5 research centers, of whom 22 patients with TAMG were finally included. This cohort had a mean age of 51.5 ± 12.1 years and an average disease duration of 4.0 ± 4.3 years. Regarding thymomas, the World Health Organization (WHO) histological classification was primarily B2 and B3 (63.7%), and Masaoka staging was predominantly IV (45.5%). Nine participants (40.9%) switched from efgartigimod to eculizumab aiming at a better clinical improvement and reducing steroid use. By week 12, the MG-ADL score decreased to 4.8 ± 4.7 (baseline: 11.7 ± 6.0), and the corticosteroid dose reduced to 23.2 ± 26.5 mg (baseline: 41.8 ± 63.9 mg). Two patients with TAMA showed significant improvement in skin lesions and thrombocytopenia. Two TEAEs were recorded including COVID-19 and herpes labialis infection. Four patients (18.2%) died of respiratory or circulatory failure owing to thymoma metastasis.

Conclusion

This real-world study demonstrates the efficacy of eculizumab in achieving symptom control and corticosteroid reduction for TAMG. It may also be a therapeutic option for refractory TAMG and TAMA.

Trial registration

NCT04535843.

Epidemiology, management and patient needs in myasthenia gravis: an Italian multistakeholder consensus based on Delphi methodology

OBJECTIVES

To provide comprehensive information on the burden of myasthenia gravis (MG) in Italy, including the unmet needs of patients and several other aspects related to the disease, based on skilled viewpoints of MG experts.

DESIGN

Iterative analysis conducted in accordance with the best practices of the Delphi method, including anonymity, controlled feedback, and statistical stability of consensus.

SETTING AND PARTICIPANTS

24 clinicians, 18 public health experts and 4 patient associations experts completed all the Delphi iterations between 18 April and 3 July 2023, for a total of 46 participants from several Italian Regions.

OUTCOME MEASURES

Five areas of investigation related to MG were examined: epidemiology in Italy and characteristics of disease; diagnostic issues and Italian patient journey; unmet needs during the acute and chronic phases of MG; quality of life; public health management of MG. Consensus in the Delphi iterations was defined by both the percentage level of agreement between panellists or the median value of the responses.

RESULTS

We reported a high level of agreement (ie, >66.7% of panellists) on the prevalence and incidence of disease in Italy and on several management issues. A strong impact of MG on the quality of life of patients also emerged. Cross-agreement was achieved among different subgroups of panellists (ie, clinicians, public health experts and patient associations representatives) for most items proposed.

CONCLUSIONS

This study provided guidance for educational and practical aspects of MG in Italy, highlighted disease severity and its role on patients' quality of life. A few gaps related to the handling of MG in Italy also emerged.

Factors affecting the diagnostic delay of myasthenia gravis

BACKGROUND

Early detection and diagnosis of myasthenia gravis (MG) is important to improve the chance of remission and overall prognosis. This study aims to investigate the factors affecting the diagnostic delay of MG thereby highlighting the challenges in the diagnostic process.

METHODS

We conducted a retrospective study examining characteristics and factors involved in the diagnostic process of MG. We included 350 patients treated for MG at the Copenhagen Neuromuscular Unit (CNMC), between 1980 and 2022. A total of 315 patients had data on time to diagnosis, which was used to categorize them into an early-and a delayed diagnosis group, based on a median cut-off of 141 days. A separate analysis was conducted for the cases with an extremely delayed time to diagnosis exceeding the upper quartile range of 864 days (n = 28). Finally, change in time to MG diagnosis over time was identified.

RESULTS

The overall mean time to diagnosis was found to be 331 days (range: 5-4492 days). Patients who experienced a delayed diagnosis were significantly younger at onset (50.4 vs. 55.4 years, p-value < 0.05), and experienced higher frequency of asymptomatic periods (29% vs. 10%, p-value < 0.05). We found a delayed referral to specialists, extended time spent at specialists, and delayed initiation of paraclinical diagnostic tests. Additionally, in the delayed group we found extended time from the initial antibody (AB) evaluation to the first positive result (3.2 vs. 86.1 days, p-value < 0.05). Individuals in the early diagnosis group may be referred to stroke specialist earlier, however, this finding was not statistically significant (18 vs. 464 days, p-value 0.17). Gender, presenting symptom, final type of MG and socioeconomic status where not associated with delayed diagnosis. Generally, a trend of decreasing time to diagnosis over time was observed.

CONCLUSION

Younger age at onset, higher prevalence of asymptomatic periods, and a delayed positive AB titer test may be risk factors for a delayed MG diagnosis. Prompt referral to a stroke specialist may lead to an earlier diagnosis.

The telemedical platform MyaLink for remote monitoring in myasthenia gravis - rationale and protocol for a proof of concept study

RATIONALE

Myasthenia gravis (MG) is a rare, chronic neurological disorder leading to fluctuating muscle weakness and potentially life-threatening crises. Patients often require life-long specialized treatment, but timely interventions are frequently hindered by the limited availability of specialists. Telemedical solutions at specialized centers enabling patient-physician interaction hold promise in bridging this gap, but are not yet available for MG. We developed 'MyaLink,' a remote monitoring platform tailored for MG, and outline the study design assessing the platform and clinical outcomes regarding telemedical intervention. Additionally, we present study results on care-related aspects in MG prior to telemedical intervention to identify challenges in the current care provision process.

DESIGN

The platform comprises a patient app and a physician portal, enabling systematic symptom monitoring using data from patient-reported outcome measures (PROMs), coupled devices and a communication module. The randomized controlled study included 45 study participants (SP) over a 12-weeks period, including a group receiving standard care (15 MG patients) and a group with additional telemedical treatment (30 MG patients) including assessment of PROMs, wearable data collection and telemedical check-ups. Questions regarding care-related aspects were assessed at baseline visit.

RESULTS

Many SP (N = 33, 73.3%) communicate with the physician managing their MG via email. 73.3% (N = 33) of SP identify areas for improvement in their MG care including symptom monitoring (N = 23, 69.7%), specialist appointment availability (N = 22, 66.7%), medication (N = 22, 66.7%) and specialist accessibility (N = 20, 60.6%). Additionally, 73.3% (N = 33) reported that the effort required to manage their MG was high.

CONCLUSION

Our results emphasize the high demand of affected MG patients for continuous telemedicine services. MyaLink can provide such a service through personalized support based on the exchange of health data. Telemedicine solutions such as MyaLink promise to improve myasthenia care by providing accessible, patient-centred care that enables early detection of worsening symptoms and non-response to treatment.

TRIAL REGISTRATION

The study was registered under DRKS00029907 on August 19, 2022.

A clinical perspective on muscle specific kinase antibody positive myasthenia gravis

The discovery of autoantibodies directed against muscle-specific kinase (MuSK) in "seronegative" myasthenia gravis (MG) patients marked a milestone in MG research. In healthy muscle, MuSK regulates a phosphorylation pathway, which is essential for the development and maintenance of acetylcholine receptor (AChR) clusters at the neuromuscular junction. Autoantibodies directed against MuSK are predominantly of the IgG4 subclass, but there is increasing evidence that IgG1-3 could also contribute to the pathology underlying MuSK-MG. MuSK-IgG4 are monovalent and block the binding site for LRP4 on MuSK, thereby inhibiting the downstream phosphorylation pathway and compromising the formation of AChR clusters. Clinically, MuSK-MG is commonly associated with the predominant involvement of bulbar, facial, shoulder and neck muscles. Cholinesterase inhibitors should be avoided in MuSK-MG due to the risk of clinical impairment and cholinergic crisis. Corticosteroids and other non-steroidal immunosuppressants are less effective with the need for higher doses and prolonged treatment. Rituximab, by contrast, has been shown to be particularly effective and is now often used early in the disease course. Its use is associated with a significant improvement in the clinical outcome of MuSK-MG patients over time. This review aims to describe the pathophysiology underlying MuSK-MG and provide a comprehensive overview of the clinical features and therapeutic options.

Design of and Early Insights From a Generalized Myasthenia Gravis Patient Engagement Research Council

Background and Aims

An exploratory focus group study was conducted to better understand the needs of patients living with generalized myasthenia gravis (gMG).

Methods

US-based adults with gMG and caregivers of patients with gMG participated in a Patient Engagement Research Council between August 2022 and January 2023. The study consisted of a 15-min prework survey, followed by virtual focus groups facilitated using a semi-structured interview guide. Data concepts were identified using conversational analysis and by direct observation. All transcripts were coded based on concepts using a qualitative research analysis program (MaxQDA).

Results

16 participants (13 patients, three caregivers) were recruited. Participants reported impact on daily activities, fatigue, and psychosocial problems. Many participants experienced delayed diagnosis and difficulty accessing specialist care. Participants described multiple barriers related to their gMG, including barriers to treatment, access-related issues, and communication disconnect between patients and healthcare professionals. Achieving stable disease was the most important goal. There was a preference for the autonomy of self-administered medications at home versus infusions. Study insights led to recommendations to guide patient and healthcare professional education.

Conclusion

The study illustrates the need to improve access to specialist care, achieve earlier diagnosis, prioritize patients' preferences in disease management, and develop treatments that improve outcomes without additional burden.

Patient or Public Contribution

The data collected in this study was provided by the focus group participants, which included patients and caregivers of those with myasthenia gravis.

Clinical and laboratory remission with rituximab in anti-MuSK-positive myasthenia gravis

BACKGROUND

Increasing data are available on the use and efficacy of rituximab (RTX) in patients with anti-muscle-specific tyrosine kinase (MuSK)-positive myasthenia gravis (MG), especially those steroid-dependent or unresponsive to traditional immunotherapies.

AIMS

We aimed to evaluate the clinical characteristics and treatment responses of adult patients with generalized anti-MuSK-positive MG treated with RTX.

METHODS

We retrospectively recruited 16 patients who were on RTX, between January 2010 and September 2023. RTX was given 1000 mg/day intravenously twice, two weeks apart. Maintenance treatment was administered at intervals of 3-6 months based on clinical evaluation. The outcome was assessed by Myasthenia Gravis Foundation of America (MGFA) and Myasthenia Gravis Status and Treatment Intensity (MGSTI) scores. Additionally, anti-MuSK antibody levels were retested after treatment in all patients except one.

RESULTS

Twelve patients were female. The mean age at disease onset was 35.3 ± 17.3 years. The median duration between disease onset and RTX administration was 2.4 years (min-max: 0.5-36.5 years). The worst MGFA class before RTX was between IIIb-V. After RTX treatment, 81.3% of patients achieved MGFA minimal manifestations or better and MGSTI level 1 or better. Anti-MuSK antibodies became negative in 12 patients, while they remained positive in three. The changes in antibody levels seemed associated with clinical outcomes.

CONCLUSIONS

RTX is an effective treatment in anti-MuSK-positive MG. Furthermore, our results support the inhibition of antibody production by RTX and we recommend monitoring anti-MuSK antibody titers to follow disease progression and treatment response.

The changing landscape of autoantibody testing in myasthenia gravis in the setting of novel drug treatments

Acquired myasthenia gravis (MG) is an autoimmune disease targeting the specific proteins in the postsynaptic muscle membrane. 50% of ocular and 80% of generalized MG have acetylcholine receptor antibodies (AChR Abs). 1-10% of MG patients have antibodies against muscle-specific kinase (MuSK), and 2-50 % of seronegative MG cases have antibodies against lipoprotein-receptor-related protein4 antibodies (LRP4 Abs). Serological testing is crucial for diagnosing and determining the appropriate therapeutic approach for MG patients. The radioimmunoprecipitation assay (RIPA) method is a historical standard test for detecting the AChR Abs and MuSK Abs. While it has nearly 100% specificity in the AChR Abs detection, its sensitivity is between 50--92%. The sensitivity and specificity of RIPA for detecting MuSK Abs is much lower. The fixed and live Cell-Based assays (f-CBA and L- CBA) have higher sensitivity than RIPA. With advancements in the serological diagnosis and management of MG, we now recommend a complete reflex testing algorithm on the first pretreatment sample of a suspected MG patient, starting with the binding and blocking assays for AChR Abs by RIPA and/ or f-CBA. If AChR Ab is negative, then reflex to MuSK Abs by RIPA and/ or CBAs. If AChR and MuSK Abs are negative, then use clustered L-CBA by request.

Risk-Benefit Analysis of Novel Treatments for Patients with Generalized Myasthenia Gravis

INTRODUCTION

This study used network meta-analysis (NMA) to inform and compare the number needed to treat (NNT), number needed to harm (NNH), and cost per improved outcome (CPIO) associated with more recently approved treatments for anti-acetylcholine receptor antibody-positive (anti-AChR Ab+) generalized myasthenia gravis (gMG).

METHODS

Clinical trials of neonatal Fc receptor (FcRn) inhibitors, efgartigimod intravenous (IV) and rozanolixizumab, and complement inhibitors, ravulizumab and zilucoplan, versus placebo (with background conventional treatment) were included in the primary NMA to compare efficacy and safety outcomes. The outputs from the NMAs were used to estimate NNT and NNH of each treatment versus placebo. CPIO (2024 USD) was estimated for a ≥ 3- or ≥ 5-point reduction from baseline in Quantitative Myasthenia Gravis (QMG) and Myasthenia Gravis-Activities of Daily Living (MG-ADL) scores. Sensitivity analyses were performed adding efgartigimod PH20 subcutaneous (SC) and eculizumab to the NMA.

RESULTS

Efgartigimod IV had the lowest NNT versus placebo for achieving a ≥ 3- and ≥ 5-point reduction in QMG, as well as a ≥ 5-point reduction in MG-ADL, whereas rozanolixizumab had the lowest NNT for a ≥ 3-point reduction in MG-ADL. The NNH versus placebo was similar across comparator treatments. Efgartigimod IV had the lowest CPIO among all treatments for all assessed efficacy outcomes. Sensitivity analyses yielded results consistent with primary analysis and indicated that efgartigimod PH20 SC had comparable NNT and CPIO values to efgartigimod IV, whereas eculizumab had comparable NNT and higher CPIO values compared to other complement inhibitors.

CONCLUSIONS

FcRn inhibitors and complement inhibitors assessed in this study all demonstrated clinical benefit in terms of NNT as well as an acceptable safety profile in terms of NNH. Within the limitations of this meta-analysis, efgartigimod was associated with a favorable benefit-risk profile as well as a better economic value compared to ravulizumab, rozanolixizumab, and zilucoplan as treatments for anti-AChR Ab+ gMG.

Therapeutic challenges and unmet needs in the management of myasthenia gravis: an Italian expert opinion

Myasthenia gravis (MG) is a rare, autoimmune, neurological disorder. Most MG patients have autoantibodies against acetylcholine receptors (AChRs). Some have autoantibodies against muscle-specific tyrosine kinase (MuSK) or lipoprotein-receptor-related protein 4 (LRP4), and some are seronegative. Standard of care, which includes anti-cholinesterase drugs, thymectomy, corticosteroids (CS), and off-label use of non-steroidal immunosuppressive drugs (NSISTs), is bounded by potential side effects and limited efficacy in refractory generalized MG (gMG) patients. This highlights the need for new therapeutic approaches for MG. Eculizumab, a monoclonal antibody that inhibits the complement system, has been recently approved in Italy for refractory gMG. A panel of 11 experts met to discuss unmet therapeutic needs in the acute and chronic phases of the disease, as well as the standard of care for refractory patients. Survival was emphasized as an acute phase outcome. In the chronic phase, persistent remission and early recognition of exacerbations to prevent myasthenic crisis and respiratory failure were considered crucial. Refractory patients require treatments with fast onset of action, improved tolerability, and the ability to slow disease progression and increase life expectancy. The Panel agreed that eculizumab would presumably meet the therapeutic needs of many refractory gMG patients. The panel concluded that the unmet needs of current standard of care treatments for gMG are significant. Evaluating new therapeutic options accurately is essential to find the best balance between efficacy and tolerability for each patient. Collecting real-world data on novel molecules in routine clinical practice is necessary to address unmet needs.

Economic and societal burden of myasthenia gravis in Denmark, Finland, and Sweden: A population-based registry study

BACKGROUND AND PURPOSE

Health care resource utilization (HCRU) and the economic burden of myasthenia gravis (MG) are significant, but existing studies rarely include comprehensive nationwide data. We examined HCRU and direct and indirect costs associated with MG overall and by disease severity in Denmark, Finland, and Sweden.

METHODS

Data were collected retrospectively from nationwide health and social care registries. All individuals ≥18 years of age with ≥2 International Classification of Diseases diagnoses of MG between 2000 and 2020 were included. HCRU, direct (inpatient and outpatient contacts, medication) and indirect costs (early retirement, sick leave, death), and associated factors were calculated.

RESULTS

The full study cohort comprised 8622 people with MG (pwMG). Mean annual numbers of all-cause secondary health care contacts for pwMG were 3.4 (SD = 8.3), 7.0 (SD = 12.3), and 2.9 (SD = 3.9), with mean annual total costs of €12,185, €9036, and €5997 per person in Denmark, Finland, and Sweden, respectively. Inpatient periods, involving 77%-89% of study participants in the three countries, contributed most to direct costs, whereas the majority of indirect costs resulted from early retirement in Denmark and Finland, and sick leave periods in Sweden. Mean annual total costs were highest with very severe MG (€19,570-€33,495 per person across the three countries). Female sex and comorbidities, such as mental and behavioral disorders and severe infections, were also associated with higher total costs.

CONCLUSIONS

This population-based study shows a high level of HCRU and a significant direct and indirect economic burden of MG across three Nordic countries, especially for severe forms of MG.

Circulating CD45RA-Foxp3++ Treg cells serve as a biomarker for predicting minimal clinical manifestations status of myasthenia gravis

AIMS

Regulatory T cells (Tregs) are key mediators of the induction of immune tolerance; however, the mechanisms by which they regulate myasthenia gravis (MG) are not fully understood. This study aimed to explore the characteristics of Tregs and their subpopulations in the peripheral blood of patients with minimal clinical manifestations (MM) of MG and identify biomarkers that predict MM-MG for treatment guidance.

MATERIALS AND METHODS

The clinical data of patients with general MG who visited our hospital were retrospectively analyzed. Age- and sex-matched volunteers were selected as healthy controls (HC). Flow cytometry was used to determine the proportion, function, and subpopulations of total Tregs. A correlation analysis was conducted for subpopulation proportions and MG disease severity.

KEY FINDINGS

A total of 27 cases of MM-MG, 40 cases of naїve-MG, and 33 cases of HC were included in this study. The number of total Tregs and the suppressive function of total Tregs were elevated in patients with MM-MG compared to those of patients with naїve-MG. Further analysis revealed that the frequency of CD45RA-Foxp3++ Tregs (a-Tregs) negatively correlated with quantitative myasthenia gravis (QMG) scores for patients with naїve-MG. In addition, the number of a-Tregs was significantly greater in patients with MM-MG than in patients with naїve-MG, and CD45RA-Foxp3+ Tregs expressed higher and lower levels of CTLA-4 and CXCR3, respectively.

SIGNIFICANCE

CD45RA-Foxp3++ Tregs were significantly more abundant and highly expressed surface inhibitory molecules in patients with MM-MG. This profile may serve as a predictive biomarker for MM-MG.

Myasthenia Gravis Complicated by M-proteinemia and Demyelinating Neuropathy: A Report of Two Cases

Myasthenia gravis (MG) is characterized by weakness and rapid fatigue of voluntary muscles. Here, we present two cases of early-onset MG, complicated with M-proteinemia and demyelinating neuropathy. Case one was diagnosed with MG at age 29, received tacrolimus post-thymectomy, and developed M-proteinemia and demyelinating neuropathies at age 66 before being diagnosed with B-cell lymphoma. Case two was diagnosed with MG at age 21, received immunosuppressive drugs post-thymectomy, and was diagnosed with myelin-associated glycoprotein antibody-associated neuropathy at age 66. Demyelinating neuropathy with M-proteinuria should be considered when motor symptoms worsen in patients with early-onset MG who receive immunosuppressive drugs after thymectomy.

Tocilizumab for the management of corticosteroid-resistant GO combined with OMG: a case series

PURPOSE

To highlight the safety and efficacy of tocilizumab (TCZ) in Graves' ophthalmopathy (GO) combined with ocular myasthenia gravis (OMG) patients refractory to steroids and cholinesterase inhibitor (CEI).

METHODS

This was retrospective case series. We reviewed the health records of patients with GO combined with OMG, ten of whom were refractory to corticosteroids and CEI treatment and received intravenous injection of TCZ. Ten patients were treated with four injections of TCZ (intravenously, 8 mg per kilogram of body weight, once a month). We analyzed the efficacy and safety of TCZ treatment for this subset of patients with GO and OMG.

RESULTS

The main outcomes including quality of life questionnaire in Graves' orbitopathy (GO-QoL) score, Clinical Activity Score (CAS), Myasthenia Gravis Activities of Daily Living profile (MG-ADL) score, proptosis, diplopia and ptosis were assessed at 3 time points: "Baseline" (before the TCZ injection), "4th month" (after fourth time TCZ injection), "Follow up" (Last follow-up). Comparing parameters at 4th month vs. at baseline, all indicators improved at 4th month including GO-QoL score of visual functioning subscale (82.29 ± 13.71 vs. 35.98 ± 20.66, P < 0.001), GO-QoL score of the appearance subscale (80 ± 8.75 vs. 40.63 ± 17.95, P < 0.001), CAS (1.3 ± 0.46 vs. 4.5 ± 0.81, P < 0.001), MG-ADL (2.5 ± 1.56 vs. 5.11 ± 1.14, P < 0.001). Furthermore, proptosis decreased from 19.73 ± 2.84 to 17.93 ± 2.26 mm at 4th month (P < 0.0001). Diplopia and ptosis were also resolved at 4th month. After following up for a minimum of 11 months, the patients had no signs of relapse. In addition, we observed that all analyzed patients exhibited no significant drug reactions following the administration of TCZ.

CONCLUSION

Tocilizumab maybe a useful therapeutic option in refractory GO coexisting with OMG. However, considering the limitation of a retrospective study, short follow up period and small sample size of this study, randomized controlled studies are needed to validate our results.

Efgartigimod treatment in patients with anti-MuSK-positive myasthenia gravis in exacerbation

Background

The prevalence of patients positive for muscle-specific kinase antibody (hereafter, MuSK-Ab) accounts for 5-8% of all myasthenia gravis (MG) cases. Currently, efgartigimod has shown good therapeutic effects in MUSK-Ab-positive MG patients in a phase III clinical trial. However, phase III clinical trials tend to exclude MG patients in exacerbation, and there are only few real-world studies on the efficacy of efgartigimod in MuSK-Ab-positive myasthenic crisis (MC) patients. This retrospective, real-world study aimed to explore the efficacy of efgartigimod in MuSK-Ab-positive MG with exacerbation.

Methods

We reviewed the clinical data of four MuSK-Ab-positive patients with exacerbation of MG who received efgartigimod at the First Affiliated Hospital of Sun Yat-sen University, including two patients with MC. All patients were admitted between September 2023 and May 2024. Most patients are simultaneously undergoing rituximab treatment.

Results

Each patient completed one cycle of efgartigimod. After the first administration, four patients showed a clinically meaningful decrease in the Myasthenia Gravis Activities of Daily Living (MG-ADL) score (a reduction of more than 4 points compared to baseline), and all patients showed a decrease in IgG levels after one cycle of efgartigimod. Regarding safety, none of the patients experienced any obvious adverse effects. At the final follow-up, all patients achieved the minimal symptom expression status (an MG-ADL score of 0 or 1) following the first administration of efgartigimod for 8.75 ± 5.56 weeks. This article presents a case involving a patient who exhibited prompt alleviation of symptoms following the administration of a high dose of efgartigimod (20 mg/kg, given on days 1 and 5), without the use of any other fast-acting treatment.

Conclusion

This retrospective real-world study demonstrates the effectiveness and safety of efgartigimod in these four MuSK-Ab-positive, female Asian patients with exacerbation of MG, as well as in patients experiencing MC. It is important to note that efgartigimod should not be viewed as a substitute for foundational immunotherapy; rather, it is intended as a rescue treatment during exacerbations and as an adjunctive therapy in the context of long-term immunotherapy. This non-invasive approach has the potential to become another treatment option for MuSK-Ab-positive MG patients.

Efgartigimod versus intravenous immunoglobulin in the treatment of patients with impending myasthenic crisis

Impending myasthenic crisis (IMC) is an emergent situation requiring aggressive management to prevent patients from developing myasthenic crisis (MC) in patients with myasthenia gravis (MG). Efgartigimod has been proved to be well tolerated and efficacious in MG patients. The present study aimed to compare the efficacy of efgartigimod and intravenous immunoglobulin (IVIg) in rescuing IMC. IMC patients treated with efgartigimod or IVIg were retrospectively enrolled. The primary outcome was determined as the mean change in MG activities of daily living (MG-ADL) score from baseline to week 1 and 4 after treatment, respectively. Safety was assessed based on medical records during the hospitalization to monitor the adverse events. A total of 9 patients treated with efgartigimod and 10 patients treated with IVIg were enrolled. There were no significant differences in the clinical characteristics at baseline between the two groups (P > 0.05). Compared with the IVIg group, the efgartigimod group had a greater reduction in the MG-ADL score at week 1 (P = 0.035) and week 4 (P = 0.005). One patient in the efgartigimod group had an upper respiratory infection. These findings suggest that efgartigimod is a treatment option for IMC in addition to IVIg and plasma exchange.

Effectiveness of double-filtration plasmapheresis in reducing immunoglobulin and culprit antibody levels in neuroimmune disorders: A single-center retrospective analysis from China

OBJECTIVE

This study aims to evaluate the effectiveness of double-filtration plasmapheresis (DFPP) in reducing immunoglobulins and culprit antibodies in neuroimmune disorders.

METHODS

A retrospective analysis was conducted on 51 patients with neuroimmune diseases treated with DFPP, immunotherapy, and symptomatic treatment. Immunoglobulin and antibody levels were measured pre- and post-treatment, along with neurological function assessments using scales like the modified Rankin Scale (mRS), Expanded Disability Status Scale (EDSS), Clinical Assessment Scale for Autoimmune Encephalitis (CASE), and Myasthenia Gravis-specific scales.

RESULTS

The cohort included patients with neuromyelitis optica spectrum disorder (NMOSD), autoimmune encephalitis (AIE), myasthenia gravis (MG), anti-myelin oligodendrocyte glycoprotein associated disease (MOGAD), and paraneoplastic neurological syndromes (PNS). DFPP significantly reduced immunoglobulin levels (IgG, IgA, IgM) by ∼70 %. Most patients showed decreased antibody titers and significant neurological improvement. The median mRS score improved from 2 (IQR 2-3) to 1 (IQR 1-2) post-treatment, with further improvement at 90 days. Notable improvements were observed across various scales specific to NMOSD, MOGAD, AIE, and MG. Minor adverse events were reported, with no serious adverse events.

CONCLUSIONS

DFPP is effective in reducing immunoglobulin and antibody levels, leading to improved neurological function in neuroimmune disorders. Further large-scale studies are warranted to confirm these findings.

Optimal time for the addition of non-corticosteroid immunosuppressants in myasthenia gravis: a single-center retrospective study in China

Introduction

Patients with myasthenia gravis (MG) display strong treatment heterogeneity. Recent studies have indicated that low-dose steroids or immunosuppressants are effective. However, factors affecting the add-on of non-corticosteroid immunosuppressants to corticosteroids remain unknown.

Method

Consecutive patients with MG were retrospectively reviewed from May 15, 2015, to December 29, 2020. We included one group of patients with steroid treatment alone and another group who transitioned to non-steroid immunosuppressant therapy. Clinical features of the included patients were analyzed. Univariate and multivariate Cox regression models were used to identify potential influential factors.

Results

A total of 107 patients with MG were analyzed, including 66 receiving corticosteroid treatment alone and 41 who subsequently also received non-corticosteroid immunosuppressant therapy. Eight potential factors were primarily selected in univariate analysis (Ps < 0.1). Achieving minimal symptom expression (MSE) within 6 months (HR: 4.424, 95%CI: 2.102-11.865), body mass index (BMI) (HR: 0.385, 95% CI: 0.186-0.797), quantitative MG (QMG) bulbar muscle score (HR: 1.553, 95% CI: 1.140-2.118), disease duration (HR: 0.987, 95% CI: 0.977-0.997) and relapse (HR: 2.638, 95% CI: 1.031-6.750) were finally identified as potential influencing factors.

Discussion

We found multifactorial clinical factors were highly associated with the add-on of non-steroid immunosuppressants after steroid treatment in patients with MG. Achieving MSE within 6 months, BMI, QMG bulbar muscle score at baseline before steroid treatment, disease duration, and disease relapse may represent crucial influencing factors, which should be considered to improve the long-term prognosis for patients with MG in future studies and practice.

Effect of thymectomy on the frequencies of peripheral regulatory B and T lymphocytes in patients with Myasthenia gravis-a pilot study

AIM

We aimed to investigate the relationship between the peripheral lymphocyte subset frequency and thymectomy in patients with myasthenia gravis (MG).

MATERIALS AND METHODS

The frequencies of regulatory B (Breg) and regulatory T (Treg) cells in peripheral blood samples obtained from 69 patients with MG and 10 healthy controls were analyzed using flow cytometry. Serum acetylcholine receptor antibodies (AchR-Ab) were measured. Patients with MG were subdivided into pre-thymectomy, post-thymectomy, and normal thymus control group.

RESULTS

The percentage of Breg cells was significantly decreased in both the pre-thymectomy (7.92 ± 1.30%) and post-thymectomy (8.14 ± 1.34%) groups compared to healthy controls (16.02 ± 2.78%) and reduced in the exacerbation and relapse phase compared to the stable maintenance stage. The proportion of cluster of differentiation (CD) 4 + CD25 + T cells and CD4 + CD25 + CD127low/- Treg cells in MG patients were not significantly different than healthy controls. AchR-Ab titers in aggravating or recurrence patients after thymectomy were significantly higher than that of the stable remission patients (11.13 ± 0.70 and 6.03 ± 0.85 nmol/L, respectively; p < 0.001).

CONCLUSION

The frequency of Breg cells may serve as a potential indicator of MG prognosis, while Treg cell frequency did not demonstrate the same prognostic ability. The concentration of AchR-Ab can be used as a dynamic monitoring index of disease severity in patients with MG.

Immune repertoire profiling in myasthenia gravis

Myasthenia gravis (MG) is the most frequent immune-mediated neurological disorder, characterized by fluctuating muscle weakness. Specific recognition of self-antigens by T-cell receptors (TCRs) and B-cell receptors (BCRs), coupled with T-B cell interactions, activates B cells to produce autoantibodies, which are critical for the initiation and perpetuation of MG. The immune repertoire comprises all functionally diverse T and B cells at a specific time point in an individual, reflecting the essence of immune selectivity. By sequencing the nucleotide sequences of TCRs and BCRs, it is possible to track individual T- and B-cell clones. This review delves into the generation of autoreactive TCRs and BCRs in MG and comprehensively examines the applications of immune repertoire sequencing in understanding disease pathogenesis, developing diagnostic and prognostic markers and informing targeted therapies. We also discuss the current limitations and future potential of this approach.

Rozanolixizumab: A New Therapy in the Treatment of Myasthenia Gravis

OBJECTIVE

The aims of this article are to review the clinical aspects of rozanolixizumab, to describe clinical trial results that led to the drug's approval, and to examine the impact on patient care to aid clinical decision making.

DATA SOURCES

A PubMed search was conducted using the terms Rystiggo™, rozanolixizumab, rozanolixizumab therapy, and myasthenia gravis. The most recent prescribing information was also used for information relating to the drug and for identification of pertinent studies.

STUDY SELECTION/DATA EXTRACTION

Phase I, II, and III randomized controlled trials were all eligible for inclusion. Meeting abstracts and articles focusing on the use of rozanolixizumab or any indication other than generalized myasthenia gravis were excluded from this article.

DATA SYNTHESIS

Food and Drug Administration approval of rozanolixizumab is based on the phase III MycarinG study in patients with generalized myasthenia gravis. A phase II trial explored initial clinical efficacy and safety pertaining to the dose and frequency of rozanolixizumab across 2 treatment periods in patients with moderate to severe myasthenia gravis.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE IN COMPARISON TO EXISTING AGENTS

Rozanolixizumab is the first therapy approved to treat patients positive for both types of antibodies, anti-acetylcholine receptor or anti-muscle-specific tyrosine kinase, in generalized myasthenia gravis.

CONCLUSION/RELEVANCE

The approval of rozanolixizumab represents an advancement in therapy for generalized myasthenia gravis. The provision of individualized, targeted, and well-tolerated treatment is valuable for the patients whose myasthenia gravis is not well controlled and who are seeking a medication with a rapid onset of action to improve their symptoms and overall quality of life.

[Benefit of treatment with rituximab in autoimmune myasthenia gravis in children]

The therapeutic management of autoimmune myasthenia gravis in children presents several particularities, which motivate the optimization of therapeutic management. On the one hand, corticosteroids are recommended as first-line immunosuppressive therapy, despite their significant adverse effects on growth, behavior, bone development, etc. On the other hand, in the absence of clinical trials in children, the place of promising new immunosuppressive therapies remains ill-defined. Rituximab is the non-steroidal immunosuppressant most widely used in France for autoimmune myasthenia gravis in children. Its use, without standardization of practices or monitoring of efficacy and safety, remains non-consensual. The aim of this study is to propose a new role for rituximab in the management of autoimmune myasthenia in children.

Intravenous Efgartigimod Alfa as Initial Monotherapy for Disabling Ocular Myasthenia in an Elderly Patient with Multiple Comorbidities

Myasthenia gravis (MG) is one of the most common neuromuscular disorders. It is an antibody-mediated autoimmune disease affecting the neuromuscular junction, presenting with fluctuating muscle weakness that commonly affects the ocular, bulbar, proximal, and respiratory muscles. Treating MG in the older population with preexisting comorbidities can be challenging. Intravenous efgartigimod alfa (EA) was successfully used as an initial monotherapy for a 90-year-old woman with acetylcholine receptor seropositive MG and stage IV colon adenocarcinoma who was referred for visually disabling bilateral eyelid ptosis. Standard MG therapy was considered but not chosen due to relative contraindications and anticipated adverse effects. EA infusions were well tolerated and corrected her ptosis after two weeks of treatment. EA infusion may be considered the first-line therapy for selected patients with seropositive generalized MG who have disabling ocular symptoms.

Autoantibodies in neuromuscular disorders: a review of their utility in clinical practice

A great proportion of neuromuscular diseases are immune-mediated, included myasthenia gravis, Lambert-Eaton myasthenic syndrome, acute- and chronic-onset autoimmune neuropathies (anti-MAG neuropathy, multifocal motor neuropathy, Guillain-Barré syndromes, chronic inflammatory demyelinating polyradiculoneuropathy, CANDA and autoimmune nodopathies), autoimmune neuronopathies, peripheral nerve hyperexcitability syndromes and idiopathic inflammatory myopathies. The detection of autoantibodies against neuromuscular structures has many diagnostic and therapeutic implications and, over time, allowed a better understanding of the physiopathology of those disorders. In this paper, we will review the main autoantibodies described in neuromuscular diseases and focus on their use in clinical practice.

275th ENMC international workshop: Seronegative myasthenia gravis: An update paradigm for diagnosis and management, 9-11 February 2024, Hoofddorp, the Netherlands

The 275th ENMC workshop on the diagnosis and management of seronegative myasthenia gravis (SNMG) was held on February 9-11, 2024. The participants included experts in the field of adult and pediatric MG together with patient representatives. This workshop aimed to redefine SNMG in view of recent diagnostic and therapeutic updates and to identify patient unmet needs. The workshop has highlighted considerable challenges in the SNMG diagnostic work-up. To date, SNMG confirmation is often controversial, given the absence of specific diagnostic tests; no recommendations from international panels of experts are available in literature; myopathies, congenital myasthenic syndromes and functional disorders are the commonest misdiagnoses. Improving the disease diagnosis is crucial to avoid long delays in receiving appropriate treatment. To this purpose, a comprehensive diagnostic algorithm achieved consensus. Moreover, a remarkable variability in SNMG response to therapy and long-term prognosis has also been highlighted.

An evaluation of ravulizumab for the treatment of neuromyelitis optica spectrum disorder

INTRODUCTION

Following the CHAMPION-NMOSD trial, the FDA recently granted approval for ravulizumab, a humanized monoclonal antibody against complement C5 protein in AQP-4 seropositive neuromyelitis optica spectrum disorder (NMOSD). Similar to eculizumab, ravulizumab offers near-complete prevention of NMOSD relapses, but has a longer half-life, providing decreased infusion frequency and increased convenience for patients. While targeting the complement pathway has clear advantages, patients are at risk for infection with encapsulated organisms, in particular Neisseria meningitidis.

AREAS COVERED

In this paper, we discuss the details of the CHAMPION-NMOSD trial and discuss challenges in meningitis prevention and strategies for switching therapies.

EXPERT OPINION

Ravulizumab improves on eculizumab's success as a highly effective NMOSD therapy by decreasing infusion frequency, thereby increasing patient convenience. We predict that ravulizumab will eventually replace eculizumab but may not have a similar impact on inebelizumab or satralizumab. Patients taking C5 complement inhibitors have an increased risk of serious meningococcal infections, such as invasive meningococcal disease (IMD), and have incomplete protection against IMD despite immunization. Thus, we recommend that in addition to standard pre-immunizations against Neisseria meningitidis, patients should also be assessed for starting on appropriate antibiotic prophylaxis against IMD, based on local resistance patterns.

Risk Stratification and Management of Acute Respiratory Failure in Patients With Neuromuscular Disease

OBJECTIVES

Guillain-Barré syndrome (GBS) and myasthenia gravis (MG) are the most common causes of acute neuromuscular respiratory failure resulting in ICU admission. This synthetic narrative review summarizes the evidence for the prediction and management of acute neuromuscular respiratory failure due to GBS and MG.

DATA SOURCES

We searched PubMed for relevant literature and reviewed bibliographies of included articles for additional relevant studies.

STUDY SELECTION

English-language publications were reviewed.

DATA EXTRACTION

Data regarding study methodology, patient population, evaluation metrics, respiratory interventions, and clinical outcomes were qualitatively assessed.

DATA SYNTHESIS

No single tool has sufficient sensitivity and specificity for the prediction of acute neuromuscular respiratory failure requiring mechanical ventilation. Multimodal assessment, integrating history, examination maneuvers (single breath count, neck flexion strength, bulbar weakness, and paradoxical breathing) and pulmonary function testing are ideal for risk stratification. The Erasmus GBS Respiratory Insufficiency Score is a validated tool useful for GBS. Noninvasive ventilation can be effective in MG but may not be safe in early GBS. Airway management considerations are similar across both conditions, but dysautonomia in GBS requires specific attention. Extubation failure is common in MG, and early tracheostomy may be beneficial for MG. Prolonged ventilatory support is common, and good functional outcomes may occur even when prolonged ventilation is required.

CONCLUSIONS

Multimodal assessments integrating several bedside indicators of bulbar and respiratory muscle function can aid in evidence-based risk stratification for respiratory failure among those with neuromuscular disease. Serial evaluations may help establish a patient's trajectory and to determine timing of respiratory intervention.

New treatment strategies in Myasthenia gravis

Myasthenia gravis (MG) is a chronic autoimmune neuromuscular disorder characterized by muscle weakness and fatigue. The disease is primarily caused by antibodies targeting acetylcholine receptors (AChR) and muscle-specific kinase (MuSK) proteins at the neuromuscular junction. Traditional treatments for MG, such as acetylcholinesterase inhibitors, corticosteroids, and immunosuppressants, have shown efficacy but are often associated with significant long-term side effects and variable patient response rates. Notably, approximately 15% of patients exhibit inadequate responses to these standard therapies. Recent advancements in molecular therapies, including monoclonal antibodies, B cell-depleting agents, complement inhibitors, Fc receptor antagonists, and chimeric antigen receptor (CAR) T cell-based therapies, have introduced promising alternatives for MG treatment. These novel therapeutic approaches offer potential improvements in targeting specific immune pathways involved in MG pathogenesis. This review highlights the progress and challenges in developing and implementing these molecular therapies. It discusses their mechanisms, efficacy, and the potential for personalized medicine in managing MG. The integration of new molecular therapies into clinical practice could significantly transform the treatment landscape of MG, offering more effective and tailored therapeutic options for patients who do not respond adequately to traditional treatments. These innovations underscore the importance of ongoing research and clinical trials to optimize therapeutic strategies and improve the quality of life for individuals with MG.

Serological Markers of Clinical Improvement in MuSK Myasthenia Gravis

BACKGROUND AND OBJECTIVES

In this retrospective longitudinal study, we aimed at exploring the role of (a) MuSK-immunoglobulin G (IgG) levels, (b) predominant MuSK-IgG subclasses, and (c) antibody affinity as candidate biomarkers of severity and outcomes in MuSK-MG, using and comparing different antibody testing techniques.

METHODS

Total MuSK-IgGs were quantified with radioimmunoassay (RIA), ELISA, flow cytometry, and cell-based assay (CBA) serial dilutions using HEK293 cells transfected with MuSK-eGFP. MuSK-IgG subclasses were measured by flow cytometry. SAffCon assay was used for determining MuSK-IgG affinity.

RESULTS

Forty-three serum samples were obtained at different time points from 20 patients with MuSK-MG (median age at onset: 48 years, interquartile range = 27.5-72.5; women, 16/20), with 9 of 20 (45%) treated with rituximab. A strong correlation between MuSK-IgG levels measured by flow cytometry and RIA titers was found (rs = 0.74, 95% CI 0.41-0.89, p = 0.0003), as well as a moderate correlation between CBA end-point titers and RIA titers (rs = 0.47, 95% CI 0.01-0.77, p = 0.0414). A significant correlation was found between MuSK-IgG flow cytometry levels and disease severity (rs = 0.39, 95% CI 0.06-0.64, p = 0.0175; mixed-effects model estimate: 2.296e-06, std. error: 1.024e-06, t = 2.243, p = 0.032). In individual patients, clinical improvement was associated with decrease in MuSK-IgG levels, as measured by either flow cytometry or CBA end-point titration. In all samples, MuSK-IgG4 was the most frequent isotype (mean ± SD: 90.95% ± 13.89). A significant reduction of MuSK-IgG4 and, to a lesser extent, of MuSK-IgG2, was seen in patients with favorable clinical outcomes. A similar trend was confirmed in the subgroup of rituximab-treated patients. In a single patient, MuSK-IgG affinity increased during symptom exacerbation (KD values: 62 nM vs 0.6 nM) while total MuSK-IgG and IgG4 levels remained stable, suggesting that affinity maturation may be a driver of clinical worsening.

DISCUSSION

Our data support the quantification of MuSK antibodies by flow cytometry. Through a multimodal investigational approach, we showed that total MuSK-IgG levels, MuSK-IgG4 and MuSK-IgG2 levels, and MuSK-IgG affinity may represent promising biomarkers of disease outcomes in MuSK-MG.

Efficacy and safety of immunosuppressants and monoclonal antibodies in adults with myasthenia gravis: a systematic review and network meta-analysis

Numerous clinical trials for myasthenia gravis (MG) treatment have been conducted recently, with satisfactory cognitive and clinical results. However, due to the limited evidence for direct comparison of the safety and effectiveness of various drugs, there is a need for further exploration of the advantages and disadvantages of different monoclonal antibodies and immunosuppressants. Thus, in the present network meta-analysis (NMA), we aimed to compare the efficacy and safety of immunosuppressants and monoclonal antibodies in treating MG. We systematically searched for randomized controlled trials published in PubMed, Embase, Web of Science, and the Cochrane Library between January 1, 2000 and March 6, 2024. Statistical analyses were performed using R software (version 4.2.3), JAGS, and STATA (version 15.0). The surface under the cumulative ranking curve (SUCRA) value was calculated to assess the potential efficacy of each drug and the likelihood of adverse events (AEs), with higher SUCRA values indicating better efficacy or a lower likelihood of AEs. This NMA included 21 randomized controlled trials involving 13 drugs and 1,657 patients. Based on changes in Quantitative MG and MG Composite scores, batoclimab was most likely to exert the best therapeutic effects, with SUCRA values of 99% and 92%, respectively. Rozanolixzumab performed better than the other drugs in terms of the MG Activities of Daily Living score (85%). Eculizumab exhibited the highest potential in reducing the 15-item revised version of the MG Quality of Life score (96%). Regarding safety, belimumab had the highest SUCRA value (85%), demonstrating the lowest likelihood of AEs. In conclusion, all immunosuppressants and monoclonal antibodies analyzed in this study were more effective than the placebo in treating MG, with rozanolixzumab and batoclimab potentially being the most effective. Regarding safety, rozanolixzumab exhibited a higher likelihood of AEs than did placebo. The conclusions guide the clinical selection of effective drugs and offer insights for future drug experiments.

Efgartigimod as a fast-acting add-on therapy in manifest and impending myasthenic crisis: A single-center case series

Efgartigimod was the first-in-class neonatal Fc receptor antagonist approved for the treatment of acetylcholine receptor antibody positive (AChR+), Myasthenia Gravis Foundation of America (MGFA) Class II-IV generalized myasthenia gravis (gMG) patients. As a novel therapy, the clinical experiences are still lacking, especially for the use of efgartigimod in manifest and impending myasthenic crisis (IMC). We reported three AChR+, gMG patients, two with myasthenic crisis (MC) and one with IMC, treated with efgartigimod. MGFA class, MG-Activity of Daily Living score (MG-ADL), Quantitative MG score (QMG), and Muscle Research Council sum score (MRC), concentration of anti-AChR antibody, IgG, globulin, and albumin, subsets of T and B lymphocyte were evaluated or measured before, during and after efgartigimod treatment. All patients showed fast and robust response to efgartigimod with marked improvement in MGFA, MG-ADL, QMG, and MRC scores. Patient 1 did not respond effectively to IVIg but was successfully rescued by add-on efgartigimod. She extubated at 7 days after the first infusion and got rid of NIV after 14-days treatment. Patient 2 and patient 3 directly used efgartigimod when symptoms were not ameliorated by adjusting of oral drugs. Patient 2 wean from BiPAP at seven days after the first infusion. Patient 3 in IMC status, overcame the severe dysphagia at three days after the first infusion. Clinical symptoms continued to improve 1-2 weeks after discharge. Concentration of anti-AChR antibody, IgG and globulin were remarkably reduced by efgartigimod treatment. Our study supported that efgartigimod could act as a fast-acting rescue therapy for patients with MC or IMC. Larger studies from multicenter are required to provide further evidence.

Efgartigimod treatment for generalized myasthenia gravis: a single-center case series of 16 patients

Background

Efgartigimod was approved in Japan in January 2022 for the treatment of generalized myasthenia gravis (gMG), regardless of antibody status. This case series describes a real-world experience in Japan of efgartigimod treatment for gMG patients with diverse backgrounds.

Methods

We retrospectively analyzed the medical records of 16 Japanese patients (11 females and five males, mean age 40.4 years) with gMG who received efgartigimod at the Kumamoto University Hospital between August 2022 and September 2023. The outcomes were Quantitative Myasthenia Gravis (QMG) responders (≥ 3 point reduction), IgG levels, and change in prednisolone dose, in the first cycle of efgartigimod.

Results

Fifteen patients completed one cycle of efgartigimod. Of the 14 patients for whom QMG scores were obtained, 10 patients were QMG responders. Four of the five patients with Myasthenia Gravis Foundation of America class V were QMG responders. Improvement in QMG after efgartigimod treatment was observed in one patient with myasthenic crisis and in one refractory patient who had unsuccessful eculizumab treatment. The mean reductions from baseline in IgG levels at weeks 1, 2, 3, and follow-up were 38.3, 56.1, 63.1, and 43.9%, respectively. A decrease in prednisolone dose was observed in seven patients. The most common adverse events were headache (three patients) and diarrhea (two patients). One patient discontinued efgartigimod treatment due to a treatment-related adverse event of rash.

Conclusion

Improvements in the outcomes of patients with gMG, including patients with severe gMG, myasthenic crisis, and refractory to anti-complementary therapy, were observed after the first cycle of efgartigimod treatment. Our real-world experience in Japan suggests the future possibilities for the treatment with efgartigimod for gMG with diverse backgrounds.

Neurologic disease in the obstetric patient

PURPOSE OF REVIEW

Neurologic disorders and complications during pregnancy are common, but guidelines and data are sparse. This review aims to give an overview of recent developments in neuroanesthesia and management of neuropathology during pregnancy, with the hope that these may fill the gaps in current guidelines and recommendations, as well as their implications for an anesthetic approach.

RECENT FINDINGS

Neuraxial and general anesthesia are safe in multiple sclerosis and myasthenia gravis, though neuromuscular blockade response is unpredictable and risk for exacerbation exists. Cerebral vascular pathology is common and carries a significant morbidity and mortality burden, but thrombolytic and endovascular therapies are often appropriate and safe. Instrumental vaginal delivery can minimize intracranial pressure shifts and is a viable option. Tumors and cerebral malformations require a complex multidisciplinary and anesthetic approach.

SUMMARY

While clinical trials remain sparse, larger population-based studies offer insight into the optimal approach to the parturient with neurologic disease.

Diagnostic value of antibody concentration ratio for treatment-refractory myasthenia gravis

OBJECTIVE

This study aimed to assess the diagnostic potential of the Antibody concentration ratio in identifying treatment-refractory myasthenia gravis (MG).

METHODS

A retrospective analysis was conducted on 116 MG patients who underwent antibody detection at least twice between June 1, 2015, and June 1, 2023. Demographic and clinical characteristics were collated to ascertain their association with refractory MG. The Antibody Concentration Ratio was applied to determine treatment response, using the International Consensus Guidance criteria as the reference standard. The area under nonparametric receiver operating characteristic curve (AUC), sensitivity, specificity, and accuracy were calculated to assess the diagnostic efficacy of the Antibody concentration ratio following consecutive immunotherapy relative to initial antibody concentrations for refractory MG.

RESULTS

19 out of 116 patients were unequivocally diagnosed with refractory MG. A significant correlation was found between the Antibody Concentration Ratio and refractory MG status in treatment-refractory and treatment-responsive patients. Subsequently, the AUC demonstrated the robust diagnostic capability of the Antibody concentration ratio for refractory MG, with an AUC of 0.8709 (95% CI: 0.7995-0.9422, p < 0.0001). The optimal cut-off value stood at 0.8903, exhibiting a sensitivity of 94.74% (95% CI: 75.36%-99.73%), a specificity of 68.04% (95% CI: 58.23%-76.48%), and accuracy of 72.41% (95% CI: 64.28%-80.54%).

CONCLUSION

Elevated Antibody Concentration Ratio is intrinsically linked with refractory MG and exhibits potential as an diagnostic biomarker for the condition.

The association between myasthenia gravis and risk of fracture: a systematic review and meta-analysis

Patients with myasthenia gravis (MG), because of their muscle weakness and exposure to corticosteroids treatment, are generally considered to be at increased risk for osteoporosis or fracture. However, clinical evidence of this issue is lacking. In this review, we systematically searched databases, including Cochrane Library, PubMed, Embase, and Airiti library from inception to the end of November 2023 for cohort studies that compared participants with MG and participants without MG for incidence of osteoporosis or fracture. We used the Newcastle-Ottawa Scale for quality assessment. In total, we included 3 studies with 34,865 participants. The pooled meta-analysis using the random effect model demonstrated no significant difference in risk of fracture in the MG group (odds ratio = 1.52; 95% confidence interval = 0.74 to 3.12; I2 = 93%; between-study variance [τ2] = 0.32) compared with that for the non-MG group. Due to limited studies, we could not perform a quantitative analysis for risk of osteoporosis. In conclusion, we found no robust evidence to support the proposition that patients with MG are at higher risk for fracture than general comparators. The explanations and underlying mechanisms of this finding remain unclear, we therefore conclude that additional studies are warranted.

Trends and Disparities in the Utilization of Thymectomy for Myasthenia Gravis in the United States

Background and Objectives

In 2016, a randomized controlled trial demonstrated the clinical efficacy of trans-sternal thymectomy for patients with non-thymomatous myasthenia gravis (MG). Whether large-scale changes occurred in clinical practice after this trial is unknown.

Methods

We performed a retrospective longitudinal cross-sectional analysis using National Inpatient Sample (NIS) data from 2012 to 2019. Our study included hospitalized adults at least 18 years of age diagnosed with MG without an associated thymoma. We used joinpoint regression to analyze annual trends in thymectomy volume and surgical approach (minimally invasive vs trans-sternal) from 2012 to 2019. Using logistic regression models, we examined patient and hospital-level factors that may have influenced whether thymectomy was performed, such as age, sex, race, insurance payor, hospital size and teaching status, and Elixhauser Comorbidity Index. Sampling weights were applied to account for the complex survey design of NIS.

Results

The total number of thymectomy procedures increased by 69.8% per year (95% CI 40.1-105.8) between 2012 and 2019. Trans-sternal thymectomies increased by 62.8% per year (95% CI 35.8-95.2) and minimally invasive thymectomies by 83.7% per year (95% CI 38.1-144.3). Thymectomies were significantly more likely to occur in 2017-2019 compared with 2012-2016 (OR 1.93, 95% CI 1.62-2.31). In a multivariable regression model, several factors decreased the odds of patients with MG having a thymectomy: older age, Black race (OR 0.62, 95% CI 0.49-0.77), female (OR 0.73, 95% CI 0.63-0.86), and higher Elixhauser Comorbidity Index. Patients in medium (OR 1.82, 95% CI 1.30-2.55) or large (OR 2.81, 95% CI 2.07-3.82) size and urban teaching hospitals (OR 6.09, 95% CI 2.65-13.97) were more likely to undergo thymectomy.

Discussion

Thymectomy is being performed more frequently for non-thymomatous MG, especially after 2016 after publication of a positive phase III clinical trial. There are several disparities in thymectomy utilization that warrant further attention.

Epidemiology of myasthenia gravis in Denmark, Finland and Sweden: a population-based observational study

BACKGROUND

Incidence and prevalence rates of myasthenia gravis (MG) vary considerably across studies, and mortality risk is rarely addressed. We examined the prevalence and incidence rates, mortality and factors associated with mortality with MG.

METHOD

This was a registry linkage study based on nationwide health and administrative registries of Denmark, Finland and Sweden (populations of 5.9, 5.6 and 10.5 million, respectively). Patients with MG were identified based on International Classification of Diseases codes from inpatient and outpatient specialised care registries. Yearly prevalence, incidence and mortality rates in relation to the total background population were calculated from 2000 to 2020 (study period). The causes of death and factors associated with mortality were addressed separately.

RESULTS

The overall incidence of MG was 1.34 (95% CI 1.27 to 1.41), 1.68 (95% CI 1.60 to 1.75) and 1.62 (95% CI 1.56 to 1.68) per 100 000, and the overall prevalence per 100 000 was 18.56 (95% CI 18.31 to 18.81), 20.89 (95% CI 20.62 to 21.16) and 23.42 (95% CI 23.21 to 23.64) in Denmark, Finland and Sweden, respectively. The overall standardised mortality ratio (SMR) was 1.32 (95% CI 1.23 to 1.42) among patients with MG in Denmark, 1.23 (95% CI 1.15 to 1.33) in Finland, and 1.20 (95% CI 1.14 to 1.26) in Sweden, with higher SMR observed in women than men. Annual incidence and prevalence increased over time, whereas the SMR remained stable. The most common causes of death were MG, chronic ischaemic heart disease and acute myocardial infarction.

CONCLUSIONS

This population-based study from three Nordic countries highlights the need for improved care of patients with MG, especially young women.

Efficacy and safety of rozanolixizumab in patients with muscle-specific tyrosine kinase autoantibody-positive generalised myasthenia gravis: a subgroup analysis of the randomised, double-blind, placebo-controlled, adaptive phase III MycarinG study

Background

Muscle-specific tyrosine kinase (MuSK) autoantibody-positive (Ab+) generalised myasthenia gravis (gMG) is a rare and frequently severe subtype of gMG.

Objectives

To assess the efficacy and safety of rozanolixizumab in the subgroup of patients with MuSK Ab+ gMG in the MycarinG study.

Design

A randomised, double-blind, placebo-controlled phase III study.

Methods

Patients with acetylcholine receptor (AChR) Ab+ or MuSK Ab+ gMG (aged ⩾18 years, Myasthenia Gravis Foundation of America Disease Class II-IVa, Myasthenia Gravis Activities of Daily Living [MG-‍ADL] score ⩾3.0 [non-ocular symptoms], Quantitative Myasthenia Gravis score ⩾11.0) were randomly assigned (1:1:1) to receive once-weekly subcutaneous infusions of rozanolixizumab 7 mg/kg, rozanolixizumab 10 mg/kg or placebo for 6 weeks, followed by an 8-week observation period. Randomisation was stratified by AChR and MuSK autoantibody status. The primary study endpoint was change from baseline to Day 43 in MG-ADL score. Treatment-emergent adverse events (TEAEs) were also assessed.

Results

Overall, 200 patients were randomised, of whom 21 had MuSK Ab+ gMG and received rozanolixizumab 7 mg/kg (n = 5), 10 mg/kg (n = 8) or placebo (n = 8). In patients with MuSK Ab+ gMG, reductions from baseline to Day 43 in MG-ADL scores were observed: rozanolixizumab 7 mg/kg least squares mean (LSM) change (standard error), -7.28 (1.94); 10 mg/kg, -4.16 (1.78); and placebo, 2.28 (1.95). Rozanolixizumab 7 mg/kg LSM difference from placebo was -9.56 (97.5% confidence interval: -15.25, -3.87); 10 mg/kg, -6.45 (-11.03, -1.86). TEAEs were experienced by four (80.0%), five (62.5%) and three (37.5%) patients with MuSK Ab+ gMG receiving rozanolixizumab 7 mg/kg, 10 mg/kg and placebo, respectively. No patients experienced serious TEAEs. No deaths occurred.

Conclusion

This subgroup analysis of adult patients with MuSK Ab+ gMG enrolled in the MycarinG study supports the use of rozanolixizumab as an effective treatment option for patients with gMG who have MuSK autoantibodies.

Trial registration

ClinicalTrials.gov: NCT03971422 (https://clinicaltrials.gov/study/NCT03971422); EU Clinical Trials Register: EudraCT 2019-000968-18 (https://www.clinicaltrials‌register.eu/ctr-search/trial/2019-000968-18/GB).

Clinical Issue of Myasthenia Gravis Related to Immune Checkpoint Inhibitors

PURPOSE OF REVIEW

Immune-related adverse events (irAEs) are pivotal in the management of immune checkpoint inhibitors (ICIs) across various human neoplasms. While common irAEs are manageable by oncologists, the detailed features of rare complications related to ICI therapy remain elusive. Among these, immune-related myasthenia gravis (irMG) stands out as a life-threatening disease.

RECENT FINDINGS

Research articles published in English between 2017 and 2023 were identified using the PubMed database. Forty-six relevant research studies were examined to collate information for this review. The incidence of ICI-induced MG was found to be less than 1.0%, with approximately 20-30% of irMG patients presenting with overlap syndrome involving myocarditis and myositis. The detection of acetylcholine receptor antibodies (AChR-Ab) and elevated creatinine kinase (CK) levels proved useful in identifying 50-70% and 60-80% of cases, respectively. However, the utility of muscle-specific kinase antibodies (MuSK-Ab) in detecting irMG was limited due to a low positivity rate (0-5.3%). Ptosis emerged as the most common initial symptom of irMG, with an approximate positivity rate of 80%. Recommended treatment for irMG involves high-dose steroids in conjunction with plasmapheresis or immunoglobulins to mitigate the increased mortality associated with irMG. Early initiation of immunosuppressive therapy is imperative to prevent the worsening of irMG. Furthermore, facilitating a fulfilling social life post-hospitalization is crucial. This review sheds light on the clinical aspects and management strategies pertaining to irMG.

Predictors of High Healthcare Cost Among Patients with Generalized Myasthenia Gravis: A Combined Machine Learning and Regression Approach from a US Payer Perspective

BACKGROUND

High healthcare costs could arise from unmet needs. This study used random forest (RF) and regression methods to identify predictors of high costs from a US payer perspective in patients newly diagnosed with generalized myasthenia gravis (gMG).

METHODS

Adults with gMG (first diagnosis = index) were selected from the IQVIA PharMetrics® Plus database (2017-2021). Predictors of high healthcare costs were measured 12 months pre-index (main cohort) and during both the 12 months pre- and post-index (subgroup). Top 50 predictors of high costs [≥ $9404 (main cohort) and ≥ $9159 (subgroup) per-patient-per-month] were identified with RF models; the magnitude and direction of association were estimated with multivariable modified Poisson regression models.

RESULTS

The main cohort and subgroup included 2739 and 1638 patients, respectively. In RF analysis, the most important predictors of high costs before/on the index date were index MG exacerbation, all-cause inpatient admission, and number of days with corticosteroids. After the index date, these were immunoglobulin and monoclonal antibody use and number of all-cause outpatient visits and MG-related encounters. Adjusting for the top 50 predictors, post-index immunoglobulin use increased the risk of high costs by 261%, monoclonal antibody use by 135%, index MG exacerbation by 78%, and pre-index all-cause inpatient admission by 27% (all p < 0.05).

CONCLUSIONS

This analysis links patient characteristics both before the formal MG diagnosis and in the first year to high future healthcare costs. Findings may help inform payers on cost-saving strategies, and providers can potentially shift to targeted treatment approaches to reduce the clinical and economic burden of gMG.

United States clinical practice experience with eculizumab in myasthenia gravis: symptoms, function, and immunosuppressant therapy use

BACKGROUND/OBJECTIVES

The phase 3 REGAIN study and its open-label extension demonstrated the efficacy of the complement C5 inhibitor eculizumab in patients with treatment-refractory, acetylcholine receptor antibody-positive generalized myasthenia gravis (gMG). The aim of the ELEVATE study was to assess the effectiveness of eculizumab in clinical practice in adults with MG in the United States.

METHODS

A retrospective chart review was conducted in adults with MG who initiated eculizumab treatment between October 23, 2017 and December 31, 2019. Outcomes assessed before and during eculizumab treatment using a pre- versus post-treatment study design included Myasthenia Gravis-Activities of Daily Living (MG-ADL) total scores; minimal symptom expression (MSE); physician impression of clinical change; minimal manifestation status (MMS); and concomitant medication use.

RESULTS

In total, 119 patients were included in the study. A significant reduction was observed in mean MG-ADL total score, from 8.0 before eculizumab initiation to 5.4 at 3 months and to 4.7 at 24 months after eculizumab initiation (both p < 0.001). At 24 months after eculizumab initiation, MSE was achieved by 19% of patients. MMS or better was achieved by 30% of patients at 24 months. Additionally, 64% of patients receiving prednisone at eculizumab initiation had their prednisone dosage reduced during eculizumab treatment and 13% discontinued prednisone; 32% were able to discontinue nonsteroidal immunosuppressant therapy.

DISCUSSION

Eculizumab treatment was associated with sustained improvements in MG-ADL total scores through 24 months in adults with MG. Prednisone dosage was reduced in approximately two-thirds of patients, suggesting a steroid-sparing effect for eculizumab.

Peripheral nervous system immune-related adverse events due to checkpoint inhibition

Immune checkpoint inhibitors have revolutionized cancer therapy and are increasingly used to treat a wide range of oncological conditions, with dramatic benefits for many patients. Unfortunately, the resulting increase in T cell effector function often results in immune-related adverse events (irAEs), which can involve any organ system, including the central nervous system (CNS) and peripheral nervous system (PNS). Neurological irAEs involve the PNS in two-thirds of affected patients. Muscle involvement (immune-related myopathy) is the most common PNS irAE and can be associated with neuromuscular junction involvement. Immune-related peripheral neuropathy most commonly takes the form of polyradiculoneuropathy or cranial neuropathies. Immune-related myopathy (with or without neuromuscular junction involvement) often occurs along with immune-related myocarditis, and this overlap syndrome is associated with substantially increased mortality. This Review focuses on PNS adverse events associated with immune checkpoint inhibition. Underlying pathophysiological mechanisms are discussed, including antigen homology between self and tumour, epitope spreading and activation of pre-existing autoreactive T cells. An overview of current approaches to clinical management is provided, including cytokine-directed therapies that aim to decouple anticancer immunity from autoimmunity and emerging treatments for patients with severe (life-threatening) presentations.

Patient and care partner perspectives and preferences related to myasthenia gravis treatment: A qualitative study

Background and Aims

Due to the high symptom and treatment burden in myasthenia gravis (MG), understanding patient and care partner perspectives and preferences is crucial.

Methods

This study used voice analysis and virtual focus groups to understand patient and care partner experiences with MG-related symptoms, treatments, and preferences. The voice analysis via social media listening used artificial intelligence-powered tools to gather and structure public digital conversations on MG. Focus groups included people living with MG and care partners who completed a questionnaire and participated in a 1-h virtual session facilitated using a semi-structured interview guide. Qualitative data were aggregated, transcribed, and thematically analyzed.

Results

The voice analysis examined 11,554 posts from 8321 individuals, discussing MG symptoms, treatments, and burden. Of 7563 symptom-related posts, 5902 (78%) conveyed negative, 1427 (19%) neutral, and 234 (3%) positive sentiment. The most frequently mentioned symptoms were categorized as dysarthria, muscle weakness, and dysphagia. MG treatment sentiment analysis identified 6667 posts (67%) as neutral, 2887 (29%) as negative, and 350 (4%) as positive. For the focus groups, 15 individuals (12 patients and 3 care partners) completed the questionnaire and 14 participated in the virtual focus group sessions. The 15 participants who completed the questionnaire prioritized treatment convenience, symptom control for improved quality of life, and preventing potential MG crises in their current treatment. New treatment expectations included increased effectiveness, less frequent dosing, faster onset, and fewer side effects. Participants were also receptive to wearable medication delivery systems placed on the body and valued direct involvement in treatment decisions.

Conclusion

Patients and care partners are often negatively impacted by MG symptoms and value convenient and fast-acting treatments that control symptoms with minimal side effects. Considering patient preferences may help optimize treatment decisions and improve patients' overall well-being and satisfaction in their care.

Efgartigimod combined with steroids as a fast-acting therapy for myasthenic crisis: a case report

BACKGROUND

Generalized myasthenia gravis (gMG) can be managed with acetylcholinesterase inhibitors (AChEis; e.g., pyridostigmine), corticosteroids, other immunosuppressive drugs (e.g., tacrolimus), and their combinations. Intravenous immunoglobulin (IVIg) or plasmapheresis (PLEX) may be administered if symptoms persist. PLEX and IVIg are also mainstays of treatment for myasthenic crisis. Recently, efgartigimod was approved in Japan for treating adults with gMG (irrespective of the antibody status) who do not have a sufficient response to corticosteroids and nonsteroidal immunosuppressive therapies. Efgartigimod is generally safe and well tolerated. However, since phase III trials of efgartigimod excluded those with myasthenic crisis, the efficacy of efgartigimod in treating myasthenic crisis is still unclear. Moreover, there are no reports that efgartigimod therapy can reduce the dose of corticosteroids needed to achieve a minimal manifestation status.

CASE PRESENTATION

We report the case of a 70-yeat-old woman with gMG who developed a myasthenic crisis. After she was diagnosed with gMG, the patient had been treated with oral corticosteroids and tacrolimus for 1 year. However, she refused to continue taking the medication, and two weeks later, she developed ptosis, dysphagia and dyspnea. The patient was intubated and treated with efgartigimod in combination with steroid therapy, and she recovered without PLEX or IVIg. Afterward, when she experienced worsening of fatigue and increased levels of anti-acetylcholine receptor antibodies, efgartigimod therapy was effective. The patient achieved minimal manifestation status even after the reduction of corticosteroids and showed improvements in the Myasthenia Gravis Activities of Daily Living scales after 4 cycles of efgartigimod infusion.

CONCLUSIONS

Our case suggests that efgartigimod can be an alternative drug for achieving minimal manifestation status in patients with myasthenic crisis. Considering its strong efficacy and safety, efgartigimod could be expanded to use as bridging therapy in the acute and chronic phases of gMG.

Serum metabolomic profile of myasthenia gravis and potential values as biomarkers in disease monitoring

OBJECTIVE

Serum metabolites from 19 myasthenia gravis (MG) patients and 15 normal controls were analyzed via untargeted metabolomics, including 6 pre/post-treatment paired MG patients, to assess the value of serum metabolites as biomarkers in monitoring MG.

METHOD

Differential metabolites between MG patients and normal controls were identified through liquid and gas chromatography-mass spectrometry simultaneously. Principal component analysis and orthogonal partial least squares-discriminant analysis were conducted to identify the differential metabolites. Candidate metabolites and pathways associated with MG were selected through a random forest machine learning model.

RESULT

A total of 310 differential metabolites were identified with a threshold of variable projected importance > 1 and P value < 0.05. Among these, 158 metabolites were upregulated and 152 were downregulated. The random forest machine learning model selected 5 metabolites as potential biomarkers associated with MG: lignoceric acid (AUC=0.944), uridine diphosphate-N-acetylglucosamine (AUC=0.951), arachidonic acid (AUC=0.951), beta-glycerophosphoric acid (AUC=0.933), and L-Asparagine (AUC=0.877). Further analysis using 6 paired MG patients pre- and post-immunosuppression treatment revealed 25 upregulated and 6 downregulated metabolites in post-treatment serum, which might be relevant to disease intervention. The significance remains elusive due to the limited number of patients.

CONCLUSION

A subset of differential metabolites was identified in the serum of MG patients, some of which changed with immunosuppressive therapy. Small molecule metabolites may serve as valuable biomarkers for disease monitoring in MG.

Recommendations for the management of myasthenia gravis in Belgium

International guidelines on the treatment of myasthenia gravis (MG) have been published but are not tailored to the Belgian situation. This publication presents recommendations from a group of Belgian MG experts for the practical management of MG in Belgium. It includes recommendations for treatment of adult patients with generalized myasthenia gravis (gMG) or ocular myasthenia gravis (oMG). Depending on the MG-related antibody a treatment sequence is suggested with therapies that can be added on if the treatment goal is not achieved. Selection of treatments was based on the level of evidence of efficacy, registration and reimbursement status in Belgium, common daily practice and the personal views and experiences of the authors. The paper reflects the situation in February 2024. In addition to the treatment considerations, other relevant aspects in the management of MG are addressed, including comorbidities, drugs aggravating disease symptoms, pregnancy, and vaccination. As many new treatments might potentially come to market, a realistic future perspective on the impact of these treatments on clinical practice is given. In conclusion, these recommendations intend to be a guide for neurologists treating patients with MG in Belgium.

Rituximab alone is as effective as associated with steroids on naive patients with generalized myasthenia gravis

INTRODUCTION

Rituximab (RTX) has been proven effective in managing refractory generalized myasthenia gravis (MG), and its use is increasing worldwide. MG stabilization may initially require oral corticosteroid (CS) therapy, but its long-term side effects require the shortest duration of treatment. We studied the clinical effectiveness and usefulness of corticosteroids associated with RTX compared to RTX alone on MG remission.

METHODS

In a monocentric retrospective cohort in the Nice University Hospital, we compared naïve MG patients treated with RTX as first-line therapy alone (G1) or associated with CS (G2). After the RTX induction, we evaluated efficacy with the Osserman score (OS) and the requirement for any rescue therapy (IVIg or plasmapheresis).

RESULTS

Sixty-eight patients were treated with RTX, of which 19 (27.94%) benefited from an association with at least 0.5 mg/kg of corticosteroids. RTX-CS patients were more severe than RTX alone (OS for G1: 74.1 and G2: 64.94, p = 0.044). However, OS at 3 (83.44 and 83.12, p = 0.993), 6 (88.69 and 86.36, p = 0.545), 9 (82.91 and 85.73, p = 0.563), and 12 months (86.6 and 88.69, p = 0.761) from the treatment induction were similar. Rescue therapy following RTX induction was significantly higher for the RTX-CS (20.41% and 47.37%, p = 0.037). Regarding safety, adverse event rates were similar in the two groups (0% and 14.29%, p = 0.178).

CONCLUSION

We suggest that RTX alone is as effective as RTX-CS in MG patients, indicating that avoiding steroids could reduce side effects, decrease rescue therapies, and not affect MG outcomes.

Treating myasthenia gravis beyond the eye clinic

Myasthenia gravis (MG) is one of the most well characterised autoimmune disorders affecting the neuromuscular junction with autoantibodies targeting the acetylcholine receptor (AChR) complex. The vast majority of patients present with ocular symptoms including double vision and ptosis, but may progress on to develop generalised fatiguable muscle weakness. Severe involvement of the bulbar muscles can lead to dysphagia, dysarthria and breathing difficulties which can progress to myasthenic crisis needing ventilatory support. Given the predominant ocular onset of the disease, it is important that ophthalmologists are aware of the differential diagnosis, investigations and management including evolving therapies. When the disease remains localised to the extraocular muscles (ocular MG) IgG1 and IgG3 antibodies against the AChR (including clustered AChR) are present in nearly 50% of patients. In generalised MG this is seen in nearly 90% patients. Other antibodies include those against muscle specific tyrosine kinase (MuSK) and lipoprotein receptor related protein 4 (LRP4). Even though decremental response on repetitive nerve stimulation is the most well recognised neurophysiological abnormality, single fibre electromyogram (SFEMG) in experienced hands is the most sensitive test which helps in the diagnosis. Initial treatment should be using cholinesterase inhibitors and then proceeding to immunosuppression using corticosteroids and steroid sparing drugs. Patients requiring bulbar muscle support may need rescue therapies including plasma exchange and intravenous immunoglobulin (IVIg). Newer therapeutic targets include those against the B lymphocytes, complement system, neonatal Fc receptors (FcRn) and various other elements of the immune system.