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Saccà F, Salort-Campana E, Jacob S, Cortés-Vicente E, Schneider-Gold C. Refocusing generalized myasthenia gravis: Patient burden, disease profiles, and the role of evolving therapy. Eur J Neurol 2024; 31:e16180. [PMID: 38117543 DOI: 10.1111/ene.16180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Revised: 11/06/2023] [Accepted: 11/27/2023] [Indexed: 12/21/2023]
Abstract
BACKGROUND AND PURPOSE Generalized myasthenia gravis (gMG) continues to present significant challenges for clinical management due to an unpredictable disease course, frequent disease fluctuations, and varying response to therapy. The recent availability of new pharmacologic therapies presents a valuable opportunity to reevaluate how this disease is classified, assessed, and managed and identify new ways to improve the clinical care of patients with gMG. METHODS Narrative review was made of publications identified via searches of PubMed and selected congresses (January 2000-September 2022). RESULTS New consensus definitions are required to ensure consistency, to better characterize patients, and to identify patients who will benefit from specific drugs and earlier use of these agents. There is a need for more frequent, standardized patient assessment to identify the cause of motor function deficits, provide a clearer picture of the disease burden and its impact on daily living and quality of life (QoL), and better support treatment decision-making. Novel approaches that target different components of the immune system will play a role in more precise treatment of patients with gMG, alongside the development of new algorithms to guide individualized patient management. CONCLUSIONS gMG has a physical, mental, and social impact, resulting in a considerable burden of disease and substantially decreased QoL, despite standard treatments. The availability of novel, targeted treatments that influence key pathological mediators of gMG, together with new biomarkers, offers the potential to optimize patient management and ultimately enables a greater number of patients to achieve minimal manifestation status and a reduced burden of disease.
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Affiliation(s)
- Francesco Saccà
- Department of Neuroscience, Reproductive Science and Odontostomatology, Federico II University, Naples, Italy
| | - Emmanuelle Salort-Campana
- Reference Center of Neuromuscular Disorders and ALS, Timone University Hospital, Assistance Publique-Hopitaux de Marseille, Marseille, France
| | - Saiju Jacob
- Institute of Immunology and Immunotherapy, University of Birmingham, Birmingham, UK
| | - Elena Cortés-Vicente
- Neuromuscular Diseases Unit, Department of Neurology, Hospital de la Santa Creu i Sant Pau and Biomedical Research Institute Sant Pau, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras, Instituto de Salud Carlos III, Madrid, Spain
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Ma C, Liu D, Wang B, Yang Y, Zhu R. Advancements and prospects of novel biologicals for myasthenia gravis: toward personalized treatment based on autoantibody specificities. Front Pharmacol 2024; 15:1370411. [PMID: 38881870 PMCID: PMC11177092 DOI: 10.3389/fphar.2024.1370411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2024] [Accepted: 05/06/2024] [Indexed: 06/18/2024] Open
Abstract
Myasthenia gravis (MG) is an antibody-mediated autoimmune disease with a prevalence of 150-250 cases per million individuals. Autoantibodies include long-lived antibodies against the acetylcholine receptor (AChR), mainly of the IgG1 subclass, and IgG4, produced almost exclusively by short-lived plasmablasts, which are prevalent in muscle-specific tyrosine kinase (MuSK) myasthenia gravis. Numerous investigations have demonstrated that MG patients receiving conventional medication today still do not possess satisfactory symptom control, indicating a substantial disease burden. Subsequently, based on the type of the autoantibody and the pathogenesis, we synthesized the published material to date and reached a conclusion regarding the literature related to personalized targeted therapy for MG. Novel agents for AChR MG have shown their efficacy in clinical research, such as complement inhibitors, FcRn receptor antagonists, and B-cell activating factor (BAFF) inhibitors. Rituximab, a representative drug of anti-CD20 therapy, has demonstrated benefits in treatment of MuSK MG patients. Due to the existence of low-affinity antibodies or unidentified antibodies that are inaccessible by existing methods, the treatment for seronegative MG remains complicated; thus, special testing and therapy considerations are necessary. It may be advantageous to initiate the application of novel biologicals at an early stage of the disease. Currently, therapies can also be combined and individualized according to different types of antibodies. With such a wide range of drugs, how to tailor treatment strategies to patients with various conditions and find the most suitable solution for each MG profile are our necessary and urgent aims.
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Affiliation(s)
- Chi Ma
- Department of Neurology, The First Affiliated Hospital of China Medical University, Shenyang, China
| | - Dan Liu
- Department of Neurology, The First Affiliated Hospital of China Medical University, Shenyang, China
| | - Benqiao Wang
- Department of Neurology, The First Affiliated Hospital of China Medical University, Shenyang, China
| | - Yingying Yang
- Department of Neurology, The First Affiliated Hospital of China Medical University, Shenyang, China
| | - Ruixia Zhu
- Department of Neurology, The First Affiliated Hospital of China Medical University, Shenyang, China
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Li Y, Yang S, Dong X, Duan W, Jiang F, Chen K, Zhou Q, Cai H, Yang H. Diagnostic value of antibody concentration ratio for treatment-refractory myasthenia gravis. Neurol Sci 2024:10.1007/s10072-024-07601-w. [PMID: 38780854 DOI: 10.1007/s10072-024-07601-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Accepted: 05/16/2024] [Indexed: 05/25/2024]
Abstract
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.
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Affiliation(s)
- Yi Li
- Department of Neurology, Research Center for Neuroimmune and Neuromuscular disorders, Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha, 410000, Hunan, China
| | - Shumei Yang
- Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha, 410000, Hunan, China
| | - Xiaohua Dong
- Department of Neurology, Research Center for Neuroimmune and Neuromuscular disorders, Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha, 410000, Hunan, China
| | - Weiwei Duan
- Department of Neurology, Research Center for Neuroimmune and Neuromuscular disorders, Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha, 410000, Hunan, China
| | - Fei Jiang
- Department of Neurology, Research Center for Neuroimmune and Neuromuscular disorders, Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha, 410000, Hunan, China
| | - Kangzhi Chen
- Department of Neurology, Research Center for Neuroimmune and Neuromuscular disorders, Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha, 410000, Hunan, China
| | - Qian Zhou
- Department of Neurology, Research Center for Neuroimmune and Neuromuscular disorders, Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha, 410000, Hunan, China
| | - Haobin Cai
- Department of Neurology, Research Center for Neuroimmune and Neuromuscular disorders, Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha, 410000, Hunan, China
| | - Huan Yang
- Department of Neurology, Research Center for Neuroimmune and Neuromuscular disorders, Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha, 410000, Hunan, China.
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Lin J, Li Y, Gui M, Bu B, Li Z. Effectiveness and safety of telitacicept for refractory generalized myasthenia gravis: a retrospective study. Ther Adv Neurol Disord 2024; 17:17562864241251476. [PMID: 38751755 PMCID: PMC11095194 DOI: 10.1177/17562864241251476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Accepted: 04/11/2024] [Indexed: 05/18/2024] Open
Abstract
Background Refractory generalized myasthenia gravis (GMG) remains a substantial therapeutic challenge. Telitacicept, a recombinant human B-lymphocyte stimulator receptor-antibody fusion protein, holds promise for interrupting the immunopathology of this condition. Objectives This study retrospectively assessed the effectiveness and safety of telitacicept in patients with refractory GMG. Design A single-center retrospective study. Methods Patients with refractory GMG receiving telitacicept (160 mg/week or biweekly) from January to September in 2023 were included. We assessed effectiveness using Myasthenia Gravis Foundation of America post-intervention status (MGFA-PIS), myasthenia gravis treatment status and intensity (MGSTI), quantitative myasthenia gravis (QMG), and MG-activity of daily living (ADL) scores, alongside reductions in prednisone dosage at 3- and 6-month intervals. Safety profiles were also evaluated. Results Sixteen patients with MGFA class II-V refractory GMG were included, with eight females and eight males. All patients were followed up for at least 3 months, and 11 patients reached 6 months follow-up. At the 3-month evaluation, 75% (12/16) demonstrated clinical improvement with MGFA-PIS. One patient achieved pharmacological remission, two attained minimal manifestation status, and nine showed functional improvement; three remained unchanged, and one deteriorated. By the 6-month visit, 90.1% (10/11) sustained significant symptomatic improvement. MGSTI scores and prednisone dosages significantly reduced at both follow-ups (p < 0.05). MG-ADL and QMG scores showed marked improvement at 6 months (p < 0.05). The treatment was well tolerated, with no severe adverse events such as allergy or infection reported. Conclusion Our exploratory investigation suggests that telitacicept is a feasible and well-tolerated add-on therapy for refractory GMG, offering valuable clinical evidence for this novel treatment option.
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Affiliation(s)
- Jing Lin
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Yue Li
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Mengcui Gui
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Bitao Bu
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Zhijun Li
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China
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Huang J, Yan Z, Song Y, Chen T. Nanodrug Delivery Systems for Myasthenia Gravis: Advances and Perspectives. Pharmaceutics 2024; 16:651. [PMID: 38794313 PMCID: PMC11125447 DOI: 10.3390/pharmaceutics16050651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2024] [Revised: 04/30/2024] [Accepted: 05/08/2024] [Indexed: 05/26/2024] Open
Abstract
Myasthenia gravis (MG) is a rare chronic autoimmune disease caused by the production of autoantibodies against the postsynaptic membrane receptors present at the neuromuscular junction. This condition is characterized by fatigue and muscle weakness, including diplopia, ptosis, and systemic impairment. Emerging evidence suggests that in addition to immune dysregulation, the pathogenesis of MG may involve mitochondrial damage and ferroptosis. Mitochondria are the primary site of energy production, and the reactive oxygen species (ROS) generated due to mitochondrial dysfunction can induce ferroptosis. Nanomedicines have been extensively employed to treat various disorders due to their modifiability and good biocompatibility, but their application in MG management has been rather limited. Nevertheless, nanodrug delivery systems that carry immunomodulatory agents, anti-oxidants, or ferroptosis inhibitors could be effective for the treatment of MG. Therefore, this review focuses on various nanoplatforms aimed at attenuating immune dysregulation, restoring mitochondrial function, and inhibiting ferroptosis that could potentially serve as promising agents for targeted MG therapy.
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Affiliation(s)
| | | | - Yafang Song
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou 510405, China; (J.H.); (Z.Y.)
| | - Tongkai Chen
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou 510405, China; (J.H.); (Z.Y.)
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Su Y, Wang X, Xing Y, Wang Z, Bu H, Cui X, Yang Y, Cai B. The analysis of factors affecting medication adherence in patients with myasthenia gravis: a cross-sectional study. Ther Adv Neurol Disord 2024; 17:17562864231206877. [PMID: 38654744 PMCID: PMC11036929 DOI: 10.1177/17562864231206877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 08/27/2023] [Indexed: 04/26/2024] Open
Abstract
Background Clinically, patients with myasthenia gravis are generally treated with drugs to improve their physical condition, and poor medication adherence can hinder their recovery. Many studies have shown the importance of medication adherence for effective treatment. Various factors may affect a patient's medication adherence; however, studies concerning medication adherence in patients with myasthenia gravis are rare. Objectives This study aimed to identify the factors related to medication adherence in patients with myasthenia gravis, and determine the possibility of predicting medication adherence. Methods This cross-sectional observational study was conducted among inpatients and outpatients with myasthenia gravis of the First Affiliated Hospital of Guangzhou University of Chinese Medicine in China. Data on patient demographics, disease-related characteristics, and medical treatment were collected. We evaluated medication adherence of the patients using the Morisky Medication Adherence Scale-8, Beliefs about Medicines Questionnaire, and the Self-efficacy for Appropriate Medication Use Scale. Results We distributed 200 questionnaires and finally retrieved 198 valid questionnaires. A total of 139 (70.2%) women participated in this study, and 81 (40.9%) among the 198 participants were aged 40-59 years. In total, 103 (52.0%) participants exhibited bad adherence to pharmacological treatment, and factors such as taking medication irregularly [odds ratio (OR) = 0.242, 95% CI = 0.093-0.627], the necessity of taking medicine (OR = 1.286, 95% CI = 1.142-1.449), the concerns of taking medicine (OR = 0.890, 95% CI = 0.801-0.988), and the self-efficacy for taking medications under difficult circumstances (OR = 1.194, 95% CI = 1.026-1.389) had statistically significant impacts on medication adherence. Conclusion Our study shows that taking medication irregularly and concerns of taking medicine are the risk factors for medication adherence. Meanwhile, the necessity of talking medicine and self-efficacy for taking medications under difficult circumstances are the protective factors for medication adherence. Our findings can help medical staff to enhance patients' medication adherence by informing patients necessary medical knowledge, emphasizing the necessity for medication, relieving patients' concerns regarding medication, and improving the self-efficacy for taking medications under difficult circumstances.
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Affiliation(s)
- Yining Su
- The First Clinical Medical School of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Xinxian Wang
- The First Clinical Medical School of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Yuemeng Xing
- The First Clinical Medical School of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Zhenni Wang
- The First Clinical Medical School of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Hailing Bu
- The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Xiaoyan Cui
- The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Yunying Yang
- The First Affiliated Hospital of Guangzhou University of Chinese Medicine, No.16 Airport Road, Baiyun District, Guangzhou, Guangdong 510405, China
| | - Bingxing Cai
- The Second Affiliated Hospital of Chongqing Medical University, No. 76 Linjiang Road, Yuzhong District, Chongqing 400010, China
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Wilcke H, Glaubitz S, Kück F, Anten C, Liebetanz D, Schmidt J, Zschüntzsch J. Female sex and overweight are associated with a lower quality of life in patients with myasthenia gravis: a single center cohort study. BMC Neurol 2023; 23:366. [PMID: 37817097 PMCID: PMC10563278 DOI: 10.1186/s12883-023-03406-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Accepted: 09/27/2023] [Indexed: 10/12/2023] Open
Abstract
BACKGROUND Myasthenia gravis (MG) affects individuals as a chronic autoimmune disease for many years. Commonly, chronic diseases significantly reduce the patients' quality of life. Aiming to improve the future quality of life in MG, this study assessed the factors impacting quality of life. As gender-specific medicine is becoming increasingly important, this study also focused on understanding gender differences in the outcome of MG. METHODS The study is a combined monocentric, retrospective and prospective database analysis of patient records based on 2,370 presentations of 165 patients with clinically, serologically and/or electrophysiologically confirmed MG over an observation period of up to 47 years. The data collection included the following parameters: antibody status, disease severity, age, medication use, gender, and disease duration. In addition, a prospective survey was conducted on the quality of life using the Myasthenia gravis-specific 15-item Quality of Life scale (MG-QoL15) and on the activities of daily living using the MG-specific Activities of Daily Living scale (MG-ADL). RESULTS Of the 165 patients, 85 were male (51.5%) and 80 were female (48.5%). The remaining baseline characteristics (e.g. age and antibody status) were consistent with other myasthenia gravis cohorts. A high body mass index (BMI) (p = 0.005) and a high disease severity (p < 0.001) were significantly associated with lower disease-specific quality of life. Additionally, the quality of life in women with MG was significantly reduced compared to male patients (19.7 vs. 13.0 points in the MG-QoL15, p = 0.024). Gender differences were also observable in terms of the period between initial manifestation and initial diagnosis and women were significantly more impaired in their activities of daily living (MG-ADL) than men (4.8 vs. 3.0 points, p = 0.032). CONCLUSION Women with MG had significantly poorer disease specific quality of life compared to men as well as patients with a higher BMI. In order to improve the quality of life, gender-specific medicine and further investigation regarding a modification of the quality of life by lowering the BMI are essential and necessary. TRIAL REGISTRATION Study approval by the Ethics Committee of the University Medical Center Göttingen was granted (number 6/5/18).
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Affiliation(s)
- Hannah Wilcke
- Department of Neurology, University Medical Center, Göttingen, Germany
| | - Stefanie Glaubitz
- Department of Neurology, University Medical Center, Göttingen, Germany
| | - Fabian Kück
- Department of Medical Statistics, University Medical Center, Göttingen, Germany
| | - Christoph Anten
- Department of Medical Statistics, University Medical Center, Göttingen, Germany
| | - David Liebetanz
- Department of Neurology, University Medical Center, Göttingen, Germany
| | - Jens Schmidt
- Department of Neurology, University Medical Center, Göttingen, Germany
- Department of Neurology and Pain Treatment, Immanuel Clinic Rüdersdorf, University Hospital of the Brandenburg Medical School Theodor Fontane, Rüdersdorf bei Berlin, Germany
- Faculty of Health Sciences Brandenburg, Brandenburg Medical School Theodor Fontane, Rüdersdorf bei Berlin, Germany
| | - Jana Zschüntzsch
- Department of Neurology, University Medical Center, Göttingen, Germany.
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Hughes T, Howard JF, Silvestri NJ, Anderson AEL, Sato M, Suchotliff S, Guptill JT, Phillips G. The economic burden of individuals living with generalized myasthenia gravis and facing social determinants of health challenges. Front Public Health 2023; 11:1247931. [PMID: 37766748 PMCID: PMC10520715 DOI: 10.3389/fpubh.2023.1247931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Accepted: 08/29/2023] [Indexed: 09/29/2023] Open
Abstract
Objective Better understanding the impact of social determinants of health (SDOH) barriers from the patient perspective is crucial to improve holistic patient support in generalized myasthenia gravis (gMG), a rare autoimmune disorder with high disease and treatment burden. The objective of this study was to identify economic challenges experienced by individuals living with gMG and SDOH barriers to better address current unmet needs. Methods Adults (18-75 years) living with gMG and experiencing SDOH barriers in the United States were recruited to a mixed-methods study including qualitative interviews and a web-based quantitative survey. Quotas were implemented to include a balanced spread of baseline demographic categories including insurance type, living environment, and employment status among the study sample. Direct and indirect economic challenges were identified by degree of concern. Results The survey was completed by 38 individuals living with gMG, the majority of whom were enrolled in public insurance and not employed. The most commonly reported major economic concerns were managing funds for emergency care (66%), loss of income (61%), and non-medical expenses (58%), highlighting the diversity of economic challenges. Individuals who were using public insurance plans, living in non-urban environments, and unemployed experienced pronounced challenges around managing non-medical costs and accessing government assistance. Conclusion Both direct and indirect costs were emphasized as major concerns among individuals living with gMG and SDOH barriers. Increasing access to relevant, personalized, and holistic resources, including care management, should be prioritized to improve disease management and outcomes for individuals living with gMG.
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Affiliation(s)
- Tom Hughes
- Argenx US Inc., Boston, MA, United States
| | - James F. Howard
- Department of Neurology, University of North Carolina, Chapel Hill, NC, United States
| | | | | | - Mai Sato
- ZS Associates, New York, NY, United States
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Huang EJC, Wu MH, Wang TJ, Huang TJ, Li YR, Lee CY. Myasthenia Gravis: Novel Findings and Perspectives on Traditional to Regenerative Therapeutic Interventions. Aging Dis 2023; 14:1070-1092. [PMID: 37163445 PMCID: PMC10389825 DOI: 10.14336/ad.2022.1215] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Accepted: 12/15/2022] [Indexed: 05/12/2023] Open
Abstract
The prevalence of myasthenia gravis (MG), an autoimmune disorder, is increasing among all subsets of the population leading to an elevated economic and social burden. The pathogenesis of MG is characterized by the synthesis of autoantibodies against the acetylcholine receptor (AChR), low-density lipoprotein receptor-related protein 4 (LRP4), or muscle-specific kinase at the neuromuscular junction, thereby leading to muscular weakness and fatigue. Based on clinical and laboratory examinations, the research is focused on distinguishing MG from other autoimmune, genetic diseases of neuromuscular transmission. Technological advancements in machine learning, a subset of artificial intelligence (AI) have been assistive in accurate diagnosis and management. Besides, addressing the clinical needs of MG patients is critical to improving quality of life (QoL) and satisfaction. Lifestyle changes including physical exercise and traditional Chinese medicine/herbs have also been shown to exert an ameliorative impact on MG progression. To achieve enhanced therapeutic efficacy, cholinesterase inhibitors, immunosuppressive drugs, and steroids in addition to plasma exchange therapy are widely recommended. Under surgical intervention, thymectomy is the only feasible alternative to removing thymoma to overcome thymoma-associated MG. Although these conventional and current therapeutic approaches are effective, the associated adverse events and surgical complexity limit their wide application. Moreover, Restivo et al. also, to increase survival and QoL, further recent developments revealed that antibody, gene, and regenerative therapies (such as stem cells and exosomes) are currently being investigated as a safer and more efficacious alternative. Considering these above-mentioned points, we have comprehensively reviewed the recent advances in pathological etiologies of MG including COVID-19, and its therapeutic management.
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Affiliation(s)
- Evelyn Jou-Chen Huang
- Department of Ophthalmology, Taipei Medical University Hospital, Taipei, Taiwan.
- Department of Ophthalmology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
| | - Meng-Huang Wu
- Department of Orthopedics, Taipei Medical University Hospital, Taipei, Taiwan.
- Department of Orthopaedics, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
| | - Tsung-Jen Wang
- Department of Ophthalmology, Taipei Medical University Hospital, Taipei, Taiwan.
- Department of Ophthalmology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
| | - Tsung-Jen Huang
- Department of Orthopedics, Taipei Medical University Hospital, Taipei, Taiwan.
- Department of Orthopaedics, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
| | - Yan-Rong Li
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Linkou Chang Gung Memorial Hospital and College of Medicine, Chang Gung University, Taoyuan, Taiwan.
| | - Ching-Yu Lee
- Department of Orthopedics, Taipei Medical University Hospital, Taipei, Taiwan.
- Department of Orthopaedics, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
- International PhD Program for Cell Therapy and Regeneration Medicine, College of Medicine, Taipei Medical University, Taipei 11031, Taiwan.
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Dalakas MC. Advances in the therapeutic algorithm for myasthenia gravis. Nat Rev Neurol 2023; 19:393-394. [PMID: 37253854 DOI: 10.1038/s41582-023-00825-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Affiliation(s)
- Marinos C Dalakas
- Department of Neurology, Thomas Jefferson University, Philadelphia, PA, USA.
- Neuroimmunology Unit, National and Kapodistrian University, University of Athens Medical School, Athens, Greece.
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Hughes T, Anderson AEL, Habib AA, Perez K, Bergin C, Suchotliff S, Zvosec C, McDaniel D, Sato M, Whangbo A, Phillips G. Impact of social determinants of health on individuals living with generalized myasthenia gravis and implications for patient support programs. Front Public Health 2023; 11:1147489. [PMID: 37275500 PMCID: PMC10235801 DOI: 10.3389/fpubh.2023.1147489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Accepted: 05/05/2023] [Indexed: 06/07/2023] Open
Abstract
Introduction Social determinants of health (SDOH) are important contributors to health outcomes, and better understanding their impact on individuals diagnosed with rare, chronic diseases with high burden and unmet need is critical. Characterizing SDOH burden can help improve the design of patient support programs (PSPs), using targeted approaches to remove barriers to access. Methods This study used a mixed-methods strategy employing a quantitative survey, which was designed based on qualitative interviews, to understand the unmet needs and awareness/utilization of PSPs among individuals living with generalized myasthenia gravis (gMG) and experiencing SDOH barriers. The survey was completed by 38 individuals living with gMG, of which the majority were non-White/Caucasian, unemployed, low income, and enrolled in public insurance. Common SDOH challenges, awareness/utilization of available PSPs, and unmet needs were identified. Results Financial and mental health concerns were the most common among individuals living with gMG and experiencing SDOH barriers throughout diagnosis, accessing treatment, initiating treatment, and continuing treatment. Awareness and utilization of existing support services were low, especially when accessing treatment. Educational, financial, and personalized support with high "human touch" were commonly perceived as the most valuable resources. Implications To better serve the needs of individuals with gMG experiencing SDOH barriers, PSPs should use a targeted approach to offer services tailored to harder-to-reach populations. Further, providers, advocacy groups, manufacturers, and public organizations in the gMG ecosystem should strengthen collaborations with PSPs to enable individuals living with gMG to access the services they need to improve their health outcomes.
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Affiliation(s)
- Tom Hughes
- argenx US Inc., Boston, MA, United States
| | | | - Ali A. Habib
- UCI Health ALS & Neuromuscular Center, University of California Irvine, Orange, CA, United States
| | | | | | | | | | | | - Mai Sato
- ZS Associates, New York, NY, United States
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Zhong H, Ruan Z, Yan C, Lv Z, Zheng X, Goh LY, Xi J, Song J, Luo L, Chu L, Tan S, Zhang C, Bu B, Da Y, Duan R, Yang H, Luo S, Chang T, Zhao C. Short-term outcome prediction for myasthenia gravis: an explainable machine learning model. Ther Adv Neurol Disord 2023; 16:17562864231154976. [PMID: 36860354 PMCID: PMC9969443 DOI: 10.1177/17562864231154976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 01/15/2023] [Indexed: 02/26/2023] Open
Abstract
Background Myasthenia gravis (MG) is an autoimmune disease characterized by muscle weakness and fatigability. The fluctuating nature of the disease course impedes the clinical management. Objective The purpose of the study was to establish and validate a machine learning (ML)-based model for predicting the short-term clinical outcome in MG patients with different antibody types. Methods We studied 890 MG patients who had regular follow-ups at 11 tertiary centers in China from 1 January 2015 to 31 July 2021 (653 patients for derivation and 237 for validation). The short-term outcome was the modified post-intervention status (PIS) at a 6-month visit. A two-step variable screening was used to determine the factors for model construction and 14 ML algorithms were used for model optimisation. Results The derivation cohort included 653 patients from Huashan hospital [age 44.24 (17.22) years, female 57.6%, generalized MG 73.5%], and the validation cohort included 237 patients from 10 independent centers [age 44.24 (17.22) years, female 55.0%, generalized MG 81.2%]. The ML model identified patients who were improved with an area under the receiver operating characteristic curve (AUC) of 0.91 [0.89-0.93], 'Unchanged' 0.89 [0.87-0.91], and 'Worse' 0.89 [0.85-0.92] in the derivation cohort, whereas identified patients who were improved with an AUC of 0.84 [0.79-0.89], 'Unchanged' 0.74 [0.67-0.82], and 'Worse' 0.79 [0.70-0.88] in the validation cohort. Both datasets presented a good calibration ability by fitting the expectation slopes. The model is finally explained by 25 simple predictors and transferred to a feasible web tool for an initial assessment. Conclusion The explainable, ML-based predictive model can aid in forecasting the short-term outcome for MG with good accuracy in clinical practice.
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Affiliation(s)
| | | | | | - Zhiguo Lv
- Department of Neurology, The Affiliated
Hospital of Changchun University of Chinese Medicine, Changchun, China
| | - Xueying Zheng
- Department of Biostatistics, School of Public
Health and Key Laboratory of Public Health Safety, Fudan University,
Shanghai, China
| | - Li-Ying Goh
- Shanghai Medical College, Fudan University,
Shanghai, China
| | - Jianying Xi
- Huashan Rare Disease Center, Department of
Neurology, Huashan Hospital, Fudan University, Shanghai, China,National Center for Neurological Disorders,
Shanghai, China
| | - Jie Song
- Huashan Rare Disease Center, Department of
Neurology, Huashan Hospital, Fudan University, Shanghai, China,National Center for Neurological Disorders,
Shanghai, China
| | - Lijun Luo
- Department of Neurology, Wuhan No.1 Hospital,
Wuhan, China
| | - Lan Chu
- Department of Neurology, The Affiliated
Hospital of Guizhou Medical University, Guiyang, China
| | - Song Tan
- Department of Neurology, Sichuan Provincial
People’s Hospital, University of Electronic Science and Technology of China,
Chengdu, China
| | - Chao Zhang
- Department of Neurology and Tianjin
Neurological Institute, Tianjin Medical University General Hospital,
Tianjin, China
| | - Bitao Bu
- Department of Neurology, Tongji Hospital,
Tongji Medical College, Huazhong University of Science and Technology,
Wuhan, China
| | - Yuwei Da
- Department of Neurology, Xuanwu Hospital,
Capital Medical University, Beijing, China
| | - Ruisheng Duan
- Department of Neurology, The First Affiliated
Hospital of Shandong First Medical University, Jinan, China
| | - Huan Yang
- Department of Neurology, Xiangya Hospital,
Central South University, Changsha, China
| | | | - Ting Chang
- Department of Neurology, Tangdu Hospital, The
Air Force Medical University, Xi’an 710000, China
| | - Chongbo Zhao
- Huashan Rare Disease Center, Department of
Neurology, Huashan Hospital, Fudan University, Shanghai 200040, China,National Center for Neurological Disorders,
Shanghai, China
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Martín Pérez SE, Martín Pérez IM, Sánchez-Romero EA, Sosa Reina MD, Muñoz Fernández AC, Alonso Pérez JL, Villafañe JH. Percutaneous Electrical Nerve Stimulation (PENS) for Infrapatellar Saphenous Neuralgia Management in a Patient with Myasthenia gravis (MG). INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:2617. [PMID: 36767982 PMCID: PMC9915414 DOI: 10.3390/ijerph20032617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 01/24/2023] [Accepted: 01/29/2023] [Indexed: 06/18/2023]
Abstract
Myasthenia gravis is a neuromuscular transmission disorder characterized by weakness of the cranial and skeletal muscles, however, neuropathies are extremely rare. In this case report we present a case of a 61-year-old man diagnosed Myasthenia gravis who came to our attention due to a 1 week of acute deep pain [NPRS 8/10] in the anterior and medial right knee which occurred during walking [NPRS 8/10] or stair climbing [NPRS 9/10]. A complete medical record and clinical examination based on physical exploration and ultrasound assessment confirmed a infrapatellar saphenous neuralgia. Therapeutic interventions included Percutaneous nerve electrical stimulation combined with pain neuroscience education, neural mobilization of the saphenous nerve and quadriceps resistance exercises. After 4 weeks, pain intensity [NRPS = 1/10], knee functionality [OKS = 41/48] and lower limb functionality [LLFI = 80%] were notably improved, nevertheless, fatigue [RPE = 2/10] was similar than baseline. At 2 months of follow-up, the effect on intensity of pain NRPS [0/10] and functionality OKS [40/48] and LLFI [82%] was maintained, however, no significant clinical changes were detected on perceived fatigue RPE Scale [2/10]. Despite the important methodological limitations of this study, our case report highlights the efficacy of percutaneous electrical nerve stimulation combined with physical agents modalities for pain and functionality of infrapatellar saphenous neuralgia in the context of Myasthenia gravis.
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Affiliation(s)
- Sebastián Eustaquio Martín Pérez
- Musculoskeletal Pain and Motor Control Research Group, Faculty of Health Sciences, Universidad Europea de Canarias, 38300 Santa Cruz de Tenerife, Spain
- Musculoskeletal Pain and Motor Control Research Group, Faculty of Sport Sciences, Universidad Europea de Madrid, 28670 Villaviciosa de Odón, Spain
- Departamento de Farmacología y Medicina Física, Área de Radiología y Medicina Física, Secciones de Enfermería y Fisioterapia, Facultad de Ciencias de la Salud, Universidad de La Laguna, 38200 Santa Cruz de Tenerife, Spain
- Escuela de Doctorado y Estudios de Posgrado, Universidad de La Laguna, 38200 Santa Cruz de Tenerife, Spain
| | - Isidro Miguel Martín Pérez
- Departamento de Farmacología y Medicina Física, Área de Radiología y Medicina Física, Secciones de Enfermería y Fisioterapia, Facultad de Ciencias de la Salud, Universidad de La Laguna, 38200 Santa Cruz de Tenerife, Spain
- Escuela de Doctorado y Estudios de Posgrado, Universidad de La Laguna, 38200 Santa Cruz de Tenerife, Spain
| | - Eleuterio A. Sánchez-Romero
- Musculoskeletal Pain and Motor Control Research Group, Faculty of Health Sciences, Universidad Europea de Canarias, 38300 Santa Cruz de Tenerife, Spain
- Musculoskeletal Pain and Motor Control Research Group, Faculty of Sport Sciences, Universidad Europea de Madrid, 28670 Villaviciosa de Odón, Spain
- Department of Physiotherapy, Faculty of Sport Sciences, Universidad Europea de Madrid, 28670 Villaviciosa de Odón, Spain
- Physiotherapy and Orofacial Pain Working Group, Sociedad Española de Disfunción Craneomandibular y Dolor Orofacial (SEDCYDO), 28009 Madrid, Spain
| | - María Dolores Sosa Reina
- Musculoskeletal Pain and Motor Control Research Group, Faculty of Sport Sciences, Universidad Europea de Madrid, 28670 Villaviciosa de Odón, Spain
- Department of Physiotherapy, Faculty of Sport Sciences, Universidad Europea de Madrid, 28670 Villaviciosa de Odón, Spain
| | - Alberto Carlos Muñoz Fernández
- Musculoskeletal Pain and Motor Control Research Group, Faculty of Sport Sciences, Universidad Europea de Madrid, 28670 Villaviciosa de Odón, Spain
- Department of Physiotherapy, Faculty of Sport Sciences, Universidad Europea de Madrid, 28670 Villaviciosa de Odón, Spain
| | - José Luis Alonso Pérez
- Musculoskeletal Pain and Motor Control Research Group, Faculty of Health Sciences, Universidad Europea de Canarias, 38300 Santa Cruz de Tenerife, Spain
- Musculoskeletal Pain and Motor Control Research Group, Faculty of Sport Sciences, Universidad Europea de Madrid, 28670 Villaviciosa de Odón, Spain
- Department of Physiotherapy, Faculty of Sport Sciences, Universidad Europea de Madrid, 28670 Villaviciosa de Odón, Spain
- Onelife Center, Multidisciplinary Pain Treatment Center, 28925 Alcorcón, Spain
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Mahic M, Bozorg A, Rudnik J, Zaremba P, Scowcroft A. Healthcare resource use in myasthenia gravis: a US health claims analysis. Ther Adv Neurol Disord 2023; 16:17562864221150327. [PMID: 36710723 PMCID: PMC9880582 DOI: 10.1177/17562864221150327] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Accepted: 12/22/2022] [Indexed: 01/26/2023] Open
Abstract
Background There are limited data on the impact of myasthenia gravis (MG) on real-world healthcare resource use (HCRU) and patient burden in the United States. Objectives This study aims to assess HCRU in patients with MG using data from a US health claims database. Design A retrospective, database study of adult patients newly diagnosed with MG, using the IBM® MarketScan® Commercial Claims and Encounters and Medicare supplemental health insurance claims database. Methods Patients with ⩾2 MG International Classification of Disease diagnosis codes ⩾3 months apart were followed from the date of their first MG diagnosis record or start of treatment. HCRU and use of immunoglobulins and plasma exchange during follow-up was assessed, as well as comorbidities, hospitalizations, emergency room (ER) visits, intensive care unit (ICU) admissions, and specialist visits per year after diagnosis, and compared with age- and sex-matched non-MG controls. Results During 2010-2019, 7194 patients were followed for up to 10 years (median = 2.3 years). During follow-up, patients with MG were 2.6-fold more likely than controls to be hospitalized, and 4.5-fold more likely to be admitted to an ICU. Risk and numbers of ER admission, hospitalization, and ICU visits were the highest in the 12 months post-diagnosis of MG and were consistently higher than controls during follow-up. MG was the main cause for most hospitalizations. Conclusion Patients with MG have higher HCRU, compared with the age- and sex-matched non-MG controls. The early years after MG diagnosis are a period of particularly high healthcare burden, with many patients requiring hospitalization and ICU care to manage serious exacerbations.
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15
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Blocking interleukin-23 ameliorates neuromuscular and thymic defects in myasthenia gravis. J Neuroinflammation 2023; 20:9. [PMID: 36639663 PMCID: PMC9837970 DOI: 10.1186/s12974-023-02691-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Accepted: 01/02/2023] [Indexed: 01/14/2023] Open
Abstract
Acetylcholine receptor (AChR) myasthenia gravis (MG) is a chronic autoimmune disease characterized by muscle weakness. The AChR+ autoantibodies are produced by B-cells located in thymic ectopic germinal centers (eGC). No therapeutic approach is curative. The inflammatory IL-23/Th17 pathway is activated in the thymus as well as in the blood and the muscle, contributing to the MG pathogenic events. We aimed to study a potential new therapeutic approach that targets IL-23p19 (IL-23) in the two complementary preclinical MG models: the classical experimental MG mouse model (EAMG) based on active immunization and the humanized mouse model featuring human MG thymuses engrafted in NSG mice (NSG-MG). In both preclinical models, the anti-IL-23 treatment ameliorated MG clinical symptoms. In the EAMG, the treatment reduced IL-17 related inflammation, anti-AChR IgG2b antibody production, activated transduction pathway involved in muscle regeneration and ameliorated the signal transduction at the neuromuscular junction. In the NSG-MG model, the treatment reduced pathogenic Th17 cell population and expression of genes involved in eGC stabilization and B-cell development in human MG thymus biopsies. Altogether, these data suggest that a therapy targeting IL-23p19 may promote significant clinical ameliorations in AChR+ MG disease due to concomitant beneficial effects on the thymus and skeletal muscle defects.
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16
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Real-world utilization patterns of intravenous immunoglobulin in adults with generalized myasthenia gravis in the United States. J Neurol Sci 2022; 443:120480. [PMID: 36347174 DOI: 10.1016/j.jns.2022.120480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 09/14/2022] [Accepted: 10/23/2022] [Indexed: 11/06/2022]
Abstract
OBJECTIVE To evaluate real-world utilization patterns of intravenous immunoglobulin (IVIg) among patients with generalized myasthenia gravis (gMG) over 3 years post-IVIg initiation. METHODS Patients with gMG who initiated IVIg treatment were identified from a United States claims database (Symphony Health's Integrated Dataverse [IDV]®, January 1, 2014 - December 31, 2019). The frequency of subsequent IVIg treatment and associated cost during the year post-IVIg initiation were analyzed. Usage patterns of IVIg and concomitant gMG treatments during the year preceding and 3 years post-IVIg initiation were compared. RESULTS Among 1225 patients with gMG who initiated IVIg treatment, 706 patients (57.6%) received 1 to 5 IVIg treatment courses (intermittent IVIg users), and 519 patients (42.4%) received ≥6 IVIg treatment courses (chronic IVIg users) within the subsequent year. Mean annual medical cost per patient was nearly 2.5-fold higher for chronic vs. intermittent IVIg users ($161,478 vs. $64,888, p < 0.001). The proportion of patients using corticosteroids and nonsteroidal immunosuppressive treatments (NSISTs) was not reduced over the 3-year follow-up period following IVIg initiation, even for patients who continued annual chronic IVIg for 3 consecutive years post-initiation. CONCLUSIONS Nearly half of patients with gMG received chronic and multiple IVIg treatment courses within the first year once initiating IVIg treatment, indicating higher usage than expected. For all IVIg initiators, the proportion of patients using corticosteroids and NSISTs did not decrease over 3 years despite IVIg initiation.
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17
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Segú-Vergés C, Caño S, Calderón-Gómez E, Bartra H, Sardon T, Kaveri S, Terencio J. Systems biology and artificial intelligence analysis highlights the pleiotropic effect of IVIg therapy in autoimmune diseases with a predominant role on B cells and complement system. Front Immunol 2022; 13:901872. [PMID: 36248801 PMCID: PMC9563374 DOI: 10.3389/fimmu.2022.901872] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 08/31/2022] [Indexed: 11/26/2022] Open
Abstract
Intravenous immunoglobulin (IVIg) is used as treatment for several autoimmune and inflammatory conditions, but its specific mechanisms are not fully understood. Herein, we aimed to evaluate, using systems biology and artificial intelligence techniques, the differences in the pathophysiological pathways of autoimmune and inflammatory conditions that show diverse responses to IVIg treatment. We also intended to determine the targets of IVIg involved in the best treatment response of the evaluated diseases. Our selection and classification of diseases was based on a previously published systematic review, and we performed the disease characterization through manual curation of the literature. Furthermore, we undertook the mechanistic evaluation with artificial neural networks and pathway enrichment analyses. A set of 26 diseases was selected, classified, and compared. Our results indicated that diseases clearly benefiting from IVIg treatment were mainly characterized by deregulated processes in B cells and the complement system. Indeed, our results show that proteins related to B-cell and complement system pathways, which are targeted by IVIg, are involved in the clinical response. In addition, targets related to other immune processes may also play an important role in the IVIg response, supporting its wide range of actions through several mechanisms. Although B-cell responses and complement system have a key role in diseases benefiting from IVIg, protein targets involved in such processes are not necessarily the same in those diseases. Therefore, IVIg appeared to have a pleiotropic effect that may involve the collaborative participation of several proteins. This broad spectrum of targets and 'non-specificity' of IVIg could be key to its efficacy in very different diseases.
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Affiliation(s)
| | - Silvia Caño
- Grifols Innovation and New Technologies (GIANT) Ltd., Dublin, Ireland
| | | | - Helena Bartra
- Health Department, Anaxomics Biotech, Barcelona, Spain
| | - Teresa Sardon
- Health Department, Anaxomics Biotech, Barcelona, Spain
| | - Srini Kaveri
- Institut National de la Santé et de la Recherche Médicale, Centre de Recherche des Cordeliers, Sorbonne Université, Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - José Terencio
- Grifols Innovation and New Technologies (GIANT) Ltd., Dublin, Ireland
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Shivaram S, Nagappa M, Varghese N, Seshagiri DV, Duble S, Siddappa SA, Hesarur N, Sinha S, Taly AB. Rituximab in Myasthenia Gravis- Experience from a Low- and Middle-Income Country (LMIC) Setting. Neurol India 2022; 70:1931-1941. [PMID: 36352590 DOI: 10.4103/0028-3886.359277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
BACKGROUND Myasthenia gravis (MG) is an immune-mediated disorder of the neuromuscular junction. About 10% are refractory to immunosuppressive therapy. AIMS To analyze the response of patients with generalized MG to rituximab. METHODS AND MATERIALS A retrospective review of patients with MG who received rituximab was carried out (n = 13, M:F = 6:7, mean age: 44.84 ± 15.73 years). Myasthenia Gravis Foundation of America (MGFA), MGFA post-intervention status (MGFA-PIS), and Myasthenia Gravis Status and Treatment Intensity (MGSTI) were assessed before and after rituximab. RESULTS The duration of MG was 104.07 ± 92.25 months. Before rituximab, the MGFA was IIA/IIB/IIIA/IIIB/IVB/V in 1/1/2/6/2/1 patients and MGSTI was four in eight patients and six in three patients. The mean duration of follow up was 20.92 ± 14.06 months (range, 4 to 42 months). Dose reduction or discontinuation of cholinesterase inhibitors could be achieved 12 patients. Complete stable remission (CSR) and pharmacologic remission (PR) were achieved in one and four patients respectively and five patients had minimal manifestations. Most patients attained level 0, 1 or 2 MGSTI at last follow up. No rituximab infusion-related adverse events were noted. Three patients had exacerbation of MG between one to five weeks after rituximab administration. Three patients died, one each due to a cardiac event unrelated to MG or treatment, complications related to myasthenic crisis, and coronavirus disease. CONCLUSIONS Rituximab was effective in bringing about remission in MG and can be considered as a first-line agent. However, it has to be administered under close supervision as some patients develop exacerbation of MG akin to steroid-induced worsening.
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Affiliation(s)
- Sumanth Shivaram
- Department of Neurology, National Institute of Mental Health and Neurosciences (NIMHANS), Bengaluru, Karnataka, India
| | - Madhu Nagappa
- Department of Neurology, National Institute of Mental Health and Neurosciences (NIMHANS), Bengaluru, Karnataka, India
| | - Nibu Varghese
- Department of Neurology, National Institute of Mental Health and Neurosciences (NIMHANS), Bengaluru, Karnataka, India
| | - Doniparthi V Seshagiri
- Department of Neurology, National Institute of Mental Health and Neurosciences (NIMHANS), Bengaluru, Karnataka, India
| | - Shishir Duble
- Department of Neurology, National Institute of Mental Health and Neurosciences (NIMHANS), Bengaluru, Karnataka, India
| | | | - Nagabushan Hesarur
- Department of Neurology, National Institute of Mental Health and Neurosciences (NIMHANS), Bengaluru, Karnataka, India
| | - Sanjib Sinha
- Department of Neurology, National Institute of Mental Health and Neurosciences (NIMHANS), Bengaluru, Karnataka, India
| | - Arun B Taly
- Department of Neurology, National Institute of Mental Health and Neurosciences (NIMHANS), Bengaluru, Karnataka, India
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Ciano-Petersen NL, Muñiz-Castrillo S, Birzu C, Vogrig A, Farina A, Villagrán-García M, Joubert B, Psimaras D, Honnorat J. Cytokine dynamics and targeted immunotherapies in autoimmune encephalitis. Brain Commun 2022; 4:fcac196. [PMID: 35999839 PMCID: PMC9392471 DOI: 10.1093/braincomms/fcac196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 04/20/2022] [Accepted: 08/16/2022] [Indexed: 11/13/2022] Open
Abstract
Autoimmune encephalitides constitute a diverse group of immune-mediated central nervous system disorders mainly characterized by the presence of antibodies targeting neuronal or glial antigens. Despite the notable contribution of antibody discovery to the understanding of their physiopathology, the specific immune cells and inflammatory mediators involved in autoimmune encephalitis are still poorly defined. However, cytokines have recently emerged as crucial signalling molecules in the pathogenesis of autoimmune encephalitis. Cytokines are biologically active, soluble, low-molecular-weight proteins or glycoproteins involved in a wide variety of physiological functions, including central nervous system development and homeostasis, immune surveillance, as well as proliferation and maturation of immune cells. Since unbalanced cytokine expression is considered a hallmark of many autoimmune central nervous system disorders, their identification and quantification has become an essential element in personalized medicine applied to the field of neuroimmunology. Several studies have explored the cytokine profile of autoimmune encephalitis, but their interpretation and comparison is challenging due to their small sample sizes and extremely high heterogeneity, especially regarding the cytokines analysed, type of sample used, and associated neural antibody. Only the cytokine profile of anti-N-methyl-D-aspartate receptor encephalitis has extensively been investigated, with findings suggesting that, although humoral immunity is the main effector, T cells may also be relevant for the development of this disorder. A better understanding of cytokine dynamics governing neuroinflammation might offer the opportunity of developing new therapeutic strategies against specific immune cells, cytokines, antibodies, or intracellular signalling cascades, therefore leading to better outcomes and preventing undesired side effects of the presently used strategies. In this review, we first summarize the current knowledge about the role of cytokines in the pathogenesis of autoimmune encephalitis, combining theoretical analysis with experimental validations, to assess their suitability as clinical biomarkers. Second, we discuss the potential applicability of the novel targeted immunotherapies in autoimmune encephalitis depending on the immunobiology of the associated antibody, their limitations, as well as the main limitations that should be addressed in future studies.
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Affiliation(s)
- Nicolás Lundahl Ciano-Petersen
- French Reference Center on Paraneoplastic Neurological Syndromes and Autoimmune Encephalitis, Hospices Civils de Lyon, Hôpital Neurologique , Bron , France
- SynatAc Team, Institute MeLiS, INSERM U1314/CNRS UMR 5284, Université de Lyon, Université Claude Bernard Lyon 1 , Lyon , France
- Neuroimmunology and Neuroinflammation group. Biomedical Research Institute of Málaga (IBIMA) , Málaga , Spain
- Red Andaluza de Investigación Clínica y Traslacional en Neurología (Neuro-RECA). Hospital Regional Universitario de Málaga , Málaga , Spain
| | - Sergio Muñiz-Castrillo
- French Reference Center on Paraneoplastic Neurological Syndromes and Autoimmune Encephalitis, Hospices Civils de Lyon, Hôpital Neurologique , Bron , France
- SynatAc Team, Institute MeLiS, INSERM U1314/CNRS UMR 5284, Université de Lyon, Université Claude Bernard Lyon 1 , Lyon , France
| | - Cristina Birzu
- Service de Neurologie 2-Mazarin, Centre de Recherche de l’Institut du Cerveau et de la Moelle Epinière, Groupe Hospitalier Pitie-Salpetrière et Université Pierre et Marie Curie-Paris 6, AP-HP , Paris , France
| | - Alberto Vogrig
- French Reference Center on Paraneoplastic Neurological Syndromes and Autoimmune Encephalitis, Hospices Civils de Lyon, Hôpital Neurologique , Bron , France
- SynatAc Team, Institute MeLiS, INSERM U1314/CNRS UMR 5284, Université de Lyon, Université Claude Bernard Lyon 1 , Lyon , France
| | - Antonio Farina
- French Reference Center on Paraneoplastic Neurological Syndromes and Autoimmune Encephalitis, Hospices Civils de Lyon, Hôpital Neurologique , Bron , France
- SynatAc Team, Institute MeLiS, INSERM U1314/CNRS UMR 5284, Université de Lyon, Université Claude Bernard Lyon 1 , Lyon , France
| | - Macarena Villagrán-García
- French Reference Center on Paraneoplastic Neurological Syndromes and Autoimmune Encephalitis, Hospices Civils de Lyon, Hôpital Neurologique , Bron , France
- SynatAc Team, Institute MeLiS, INSERM U1314/CNRS UMR 5284, Université de Lyon, Université Claude Bernard Lyon 1 , Lyon , France
| | - Bastien Joubert
- French Reference Center on Paraneoplastic Neurological Syndromes and Autoimmune Encephalitis, Hospices Civils de Lyon, Hôpital Neurologique , Bron , France
- SynatAc Team, Institute MeLiS, INSERM U1314/CNRS UMR 5284, Université de Lyon, Université Claude Bernard Lyon 1 , Lyon , France
| | - Dimitri Psimaras
- Service de Neurologie 2-Mazarin, Centre de Recherche de l’Institut du Cerveau et de la Moelle Epinière, Groupe Hospitalier Pitie-Salpetrière et Université Pierre et Marie Curie-Paris 6, AP-HP , Paris , France
| | - Jérôme Honnorat
- French Reference Center on Paraneoplastic Neurological Syndromes and Autoimmune Encephalitis, Hospices Civils de Lyon, Hôpital Neurologique , Bron , France
- SynatAc Team, Institute MeLiS, INSERM U1314/CNRS UMR 5284, Université de Lyon, Université Claude Bernard Lyon 1 , Lyon , France
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Dalakas MC. Role of complement, anti-complement therapeutics, and other targeted immunotherapies in myasthenia gravis. Expert Rev Clin Immunol 2022; 18:691-701. [PMID: 35730504 DOI: 10.1080/1744666x.2022.2082946] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
INTRODUCTION Several patients with myasthenia gravis (MG) do not adequately respond to available drugs or exhibit poor tolerance, necessitating the need for new therapies. AREAS COVERED The paper discusses the rapidly evolving target-specific immunotherapies that promise long-standing remissions in the management of MG. It is specifically focused on the role of complement, anti-complement therapeutics, and the anti-FcRn and B cell monoclonals. EXPERT OPINION Anti-AChR antibodies cause internalization of the receptors and activate complement leading to in situ MAC formation that damages the post-synaptic membrane of the neuromuscular junction. Inhibiting MAC formation by antibodies targeting key complements subcomponents is a reasonable therapeutic goal. Indeed, the anti-C5 monoclonal antibodies, Eculizumab, Ravulizumab, and Zilucoplan, have been successfully tested in MG with Eculizumab first and now Ravulizumab FDA-approved for refractory MG based on sustained long-term benefits. Among the biologics that inhibit FcRn, Efgartigimod caused rapid reduction of the circulating IgG in the lysosomes, and induced sustained clinical remission with good safety profile leading to FDA-approved indication. Anti-B cell agents, like Rituximab, can induce sustained long-term remissions, especially in IgG4 antibody-mediated Musk-MG, by targeting short-lived antibody-secreting plasmablasts. These biologics offer effective targeted immunotherapies with good tolerance promising to change the therapeutic algorithm in the chronic MG management.
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Affiliation(s)
- Marinos C Dalakas
- Department of Neurology, Thomas Jefferson University, Philadelphia, PA, USA.,Neuroimmunology Unit, National and Kapodistrian University, University of Athens Medical School, Athens, Greece
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21
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Dalakas MC. Autoimmune Neurological Disorders with IgG4 Antibodies: a Distinct Disease Spectrum with Unique IgG4 Functions Responding to Anti-B Cell Therapies. Neurotherapeutics 2022; 19:741-752. [PMID: 35290608 PMCID: PMC9294117 DOI: 10.1007/s13311-022-01210-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/18/2022] [Indexed: 11/26/2022] Open
Abstract
The main IgG4 antibody-mediated neurological disorders (IgG4-ND) include MuSK myasthenia; CIDP with nodal/paranodal antibodies to Neurofascin-155, contactin-1/caspr-1, or pan-neurofascins; anti-LGI1 and CASPR2-associated limbic encephalitis, Morvan syndrome, or neuromyotonia; and several cases of the anti-IgLON5 and anti-DPPX-spectrum CNS diseases. The paper is centered on the clinical spectrum of IgG4-ND and their immunopathogenesis highlighting the unique functional effects of the IgG4 subclass compared to IgG1-3 antibody subclasses. The IgG4 antibodies exert pathogenic effects on their targeted antigens by blocking enzymatic activity or disrupting protein-protein interactions affecting signal transduction pathways, but not by activating complement, binding to inhibitory FcγRIIb receptor or engaging in cross-linking of the targeted antigen with immune complex formation as the IgG1-IgG3 antibody subclasses do. IgG4 can even inhibit the classical complement pathway by affecting the affinity of IgG1-2 subclasses to C1q binding. Because the IgG4 antibodies do not trigger inflammatory processes or complement-mediated immune responses, the conventional anti-inflammatory therapies, especially with IVIg, immunosuppressants, and plasmapheresis, are ineffective or not sufficiently effective in inducing long-term remissions. In contrast, aiming at the activated plasmablasts connected with IgG4 antibody production is a meaningful therapeutic target in IgG4-ND. Indeed, data from large series of patients with MuSK myasthenia, CIDP with nodal/paranodal antibodies, and anti-LGI1 and CASPR2-associated syndromes indicate that B cell depletion therapy with rituximab exerts long-lasting clinical remissions by targeting memory B cells and IgG4-producing CD20-positive short-lived plasma cells. Because IgG4 antibody titers seem reduced in remissions and increased in exacerbation, they may serve as potential biomarkers of treatment response supporting further the pathogenic role of self-reacting B cells. Controlled trials are needed in IgG4-ND not only with rituximab but also with the other anti-B cell agents that target CD19/20, especially those like obexelimab and obinutuzumab, that concurrently activate the inhibitory FcγRIIb receptors which have low binding affinity to IgG4, exerting a more prolonged anti-B cell action affecting also antigen presentation and cytotoxic T cells. Antibody therapies targeting FcRn, testing those anti-FcRn inhibitors that effectively catabolize the IgG4 antibody subclass, may be especially promising.
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Affiliation(s)
- Marinos C Dalakas
- Department of Neurology, Thomas Jefferson University, Philadelphia, PA, USA.
- Neuroimmunology Unit National and Kapodistrian University of Athens Medical School, Athens, Greece.
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22
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Dalakas MC, Meisel A. Immunomodulatory effects and clinical benefits of intravenous immunoglobulin in myasthenia gravis. Expert Rev Neurother 2022; 22:313-318. [PMID: 35350948 DOI: 10.1080/14737175.2022.2057223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
INTRODUCTION Myasthenia gravis (MG) is an antibody-mediated disease that develops in the majority of patients mainly as a result of acetylcholine receptor (AChR) autoantibodies. This process is mediated by a series of immunoregulatory events. Therapeutic targets for MG include suppression of circulating antibodies or antibody production, suppression of complement activation, and immunomodulation of cytokines or T cells. Intravenous immunoglobulin (IVIg) has an effect on all of these mechanisms. AREAS COVERED This narrative review explores the broad immunomodulatory effects of IVIg in MG and provides an update on IVIg treatment for MG. EXPERT OPINION IVIg has a range of immunomodulatory effects on therapeutic targets relevant to the immunopathogenesis of MG. An emerging area of research is the pharmacogenomics of IVIg in MG related to FcRn and IgG catabolism. New data indicate that the FcRn VNTR3 genotype can affect the efficacy of IVIg in certain MG patients and may have an impact on IgG kinetics and selected dosing. Immune globulin 10% caprylate/chromatography purified (IVIg-C) has been shown to reverse the symptoms of severe acute exacerbation in patients with MG. Available data support the use of IVIg-C as an effective and safe treatment for this severely ill subgroup of patients during a relapse.
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Affiliation(s)
- Marinos C Dalakas
- Department of Neurology, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Andreas Meisel
- Department of Neurology, Integrated Center for Myasthenia Gravis, Charité - University Medicine Berlin, Germany
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Verschuuren JJGM, Palace J, Murai H, Tannemaat MR, Kaminski HJ, Bril V. Advances and ongoing research in the treatment of autoimmune neuromuscular junction disorders. Lancet Neurol 2022; 21:189-202. [DOI: 10.1016/s1474-4422(21)00463-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 11/16/2021] [Accepted: 12/17/2021] [Indexed: 12/14/2022]
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Cortés-Vicente E, Álvarez-Velasco R, Pla-Junca F, Rojas-Garcia R, Paradas C, Sevilla T, Casasnovas C, Gómez-Caravaca MT, Pardo J, Ramos-Fransi A, Pelayo-Negro AL, Gutiérrez-Gutiérrez G, Turon-Sans J, López de Munain A, Guerrero-Sola A, Jericó I, Martín MA, Mendoza MD, Morís G, Vélez-Gómez B, Garcia-Sobrino T, Pascual-Goñi E, Reyes-Leiva D, Illa I, Gallardo E. Drug-refractory myasthenia gravis: Clinical characteristics, treatments, and outcome. Ann Clin Transl Neurol 2022; 9:122-131. [PMID: 35080153 PMCID: PMC8862423 DOI: 10.1002/acn3.51492] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 12/09/2021] [Accepted: 12/09/2021] [Indexed: 01/20/2023] Open
Abstract
Objective To describe the clinical characteristics and outcomes in patients with refractory myasthenia gravis (MG) and to determine the effectiveness and side effects of the drugs used for their treatment. Methods This observational retrospective cross‐sectional multicenter study was based on data from the Spanish MG Registry (NMD‐ES). Patients were considered refractory when their MG Foundation of America post‐interventional status (MGFA‐PIS) was unchanged or worse after corticosteroids and two or more other immunosuppressive agents. Clinical and immunologic characteristics of drug‐refractory patients, efficiency and toxicity of drugs used, and outcome (MGFA‐PIS) at end of follow‐up were studied. Results We included 990 patients from 15 hospitals. Eighty‐four patients (68 of 842 anti‐acetylcholine receptor [AChR], 5 of 26 anti‐muscle‐specific tyrosine kinase [MusK], 10 of 120 seronegative, and 1 of 2 double‐seropositive patients) were drug refractory. Drug‐refractory patients were more frequently women (p < 0.0001), younger at onset (p < 0.0001), and anti‐MuSK positive (p = 0.037). Moreover, they more frequently presented a generalized form of the disease, bulbar symptoms, and life‐threatening events (p < 0.0001; p = 0.018; and p = 0.002, respectively) than non‐drug‐refractory patients. Mean follow‐up was 9.8 years (SD 4.5). Twenty‐four (50%) refractory patients had side effects to one or more of the drugs. At the end of follow‐up, 42.9% of drug‐refractory patients (42.6% of anti‐AChR, 100% of anti‐MuSK, and 10% of seronegative patients) and 79.8% of non‐drug‐refractory patients (p < 0.0001) achieved remission or had minimal manifestations. Eighty percent of drug‐refractory‐seronegative patients did not respond to any drug tested. Interpretation In this study, 8.5% of MG patients were drug‐refractory. New more specific drugs are needed to treat drug‐refractory MG patients.
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Affiliation(s)
- Elena Cortés-Vicente
- Neuromuscular Diseases Unit, Department of Neurology, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.,Department of Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain.,Biomedical Research Institute Sant Pau (IIB Sant Pau), Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
| | - Rodrigo Álvarez-Velasco
- Neuromuscular Diseases Unit, Department of Neurology, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.,Department of Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain.,Biomedical Research Institute Sant Pau (IIB Sant Pau), Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
| | - Francesc Pla-Junca
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
| | - Ricard Rojas-Garcia
- Neuromuscular Diseases Unit, Department of Neurology, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.,Department of Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain.,Biomedical Research Institute Sant Pau (IIB Sant Pau), Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
| | - Carmen Paradas
- Neurology Department, Neuromuscular Disorders Unit, Instituto de Biomedicina de Sevilla, Hospital U. Virgen del Rocío, CSIC, Universidad de Sevilla, Sevilla, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Instituto de Salud Carlos III, Madrid, Spain
| | - Teresa Sevilla
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, Madrid, Spain.,Neuromuscular Unit, Neurology Department, Hospital Universitari i Politècnic La Fe, Valencia, Spain.,Department of Medicine, Universitat de València, Valencia, Spain.,Biomedical Research Institute La Fe (IIS La Fe), Valencia, Spain
| | - Carlos Casasnovas
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, Madrid, Spain.,Unitat de Neuromuscular, Neurology Department, Hospital Universitari de Bellvitge - IDIBELL, L'Hospitalet de Llobregat, Barcelona, Spain
| | | | - Julio Pardo
- Neurology Department, Hospital Clínico, Santiago de Compostela, Spain
| | - Alba Ramos-Fransi
- Department of Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain.,Neuromuscular Diseases Unit, Department of Neurology, Hospital Germans Trias i Pujol, Badalona, Barcelona, Spain
| | - Ana Lara Pelayo-Negro
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Instituto de Salud Carlos III, Madrid, Spain.,Service of Neurology, University Hospital "Marqués de Valdecilla (IDIVAL)", University of Cantabria (UC), Santander, Spain
| | - Gerardo Gutiérrez-Gutiérrez
- Neuromuscular Diseases Unit, Department of Neurology, Hospital Universitario Infanta Sofía, Universidad Europea de Madrid, San Sebastián de los Reyes, Madrid, Spain
| | - Janina Turon-Sans
- Neuromuscular Diseases Unit, Department of Neurology, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.,Department of Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain.,Biomedical Research Institute Sant Pau (IIB Sant Pau), Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
| | - Adolfo López de Munain
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Instituto de Salud Carlos III, Madrid, Spain.,Neurology Department, Donostia University Hospital, University of the Basque Country, Neurosciences Area, Biodonostia Research Institute, San Sebastián, Spain
| | - Antonio Guerrero-Sola
- Neuromuscular Diseases Unit, Department of Neurology, Institute of Neurosciences, Hospital Universitario Clínico San Carlos, Madrid, Spain
| | - Ivonne Jericó
- Department of Neurology, Complejo Hospitalario de Navarra-IdisNA, Pamplona, Spain
| | | | - María Dolores Mendoza
- Department of Neurology, Hospital Universitario de Gran Canaria Doctor Negrín, Las Palmas de Gran Canaria, Spain
| | - Germán Morís
- Department of Neurology, Hospital Central de Asturias, Oviedo, Spain
| | - Beatriz Vélez-Gómez
- Neurology Department, Neuromuscular Disorders Unit, Instituto de Biomedicina de Sevilla, Hospital U. Virgen del Rocío, CSIC, Universidad de Sevilla, Sevilla, Spain
| | | | - Elba Pascual-Goñi
- Neuromuscular Diseases Unit, Department of Neurology, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.,Department of Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain.,Biomedical Research Institute Sant Pau (IIB Sant Pau), Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
| | - David Reyes-Leiva
- Neuromuscular Diseases Unit, Department of Neurology, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.,Department of Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain.,Biomedical Research Institute Sant Pau (IIB Sant Pau), Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
| | - Isabel Illa
- Neuromuscular Diseases Unit, Department of Neurology, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.,Department of Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain.,Biomedical Research Institute Sant Pau (IIB Sant Pau), Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
| | - Eduard Gallardo
- Neuromuscular Diseases Unit, Department of Neurology, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.,Department of Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain.,Biomedical Research Institute Sant Pau (IIB Sant Pau), Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
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25
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Dalakas MC. IgG4-Mediated Neurologic Autoimmunities: Understanding the Pathogenicity of IgG4, Ineffectiveness of IVIg, and Long-Lasting Benefits of Anti-B Cell Therapies. NEUROLOGY(R) NEUROIMMUNOLOGY & NEUROINFLAMMATION 2022; 9:9/1/e1116. [PMID: 34845096 PMCID: PMC8630661 DOI: 10.1212/nxi.0000000000001116] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Accepted: 10/08/2021] [Indexed: 12/15/2022]
Abstract
BACKGROUND AND OBJECTIVES Describe the unique functions of immunoglobulin G4 (IgG4) in IgG4-neurologic disorders (IgG4-ND) and explain why, in contrast to their IgG1-counterparts, they respond poorly to intravenous immune globulin (IVIg) but effectively to anti-B cell therapies. METHODS The IgG4 structure and isotype switch, B cells and plasmablasts relevant to IgG4 production, and IgG4-induced disruption of the targeted antigens are reviewed and compared with IgG1-mediated autoimmune ND, where IVIg inhibits IgG1-triggered inflammatory effects. RESULTS The main IgG4-ND include muscle-specific kinase myasthenia; nodal/paranodal chronic inflammatory demyelinating polyradiculoneuropathy with antibodies to neurofascin-155, contactin-1/caspr-1, or pan-neurofascins; antileucine-rich, glioma-inactivated-1 and contactin-associated protein-like 2 associated-limbic encephalitis, Morvan syndrome, or neuromyotonia; and anti-IgLON5 disorder. The IgG4, because of its unique structural features in the hinge region, has noninflammatory properties being functionally monovalent and bispecific, unable to engage in cross-linking and internalization of the targeted antigen. In contrast to IgG1 subclass which is bivalent and monospecific, IgG4 does not activate complement and cannot bind to inhibitory Fcγ receptor (FcγRIIb) to activate cellular and complement-mediated immune responses, the key functions inhibited by IVIg. Because IVIg contains only 0.7%-2.6% IgG4, its idiotypes are of IgG1 subclass and cannot effectively neutralize IgG4 or sufficiently enhance IgG4 catabolism by saturating FcRn. In contrast, rituximab, by targeting memory B cells and IgG4-producing CD20-positive short-lived plasma cells, induces long-lasting clinical benefits. DISCUSSION Rituximab is the preferred treatment in IgG4-ND patients with severe disease by effectively targeting the production of pathogenic IgG-4 antibodies. In contrast, IVIG is ineffective because it inhibits immunoinflammatory functions irrelevant to the mechanistic effects of IgG4 and contains IgG-1 idiotypes that cannot sufficiently neutralize or possibly catabolize IgG4. Controlled studies with anti-CD19/20 monoclonals that also activate FcγRIIb may be more promising in treating IgG4-ND.
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Affiliation(s)
- Marinos C Dalakas
- From Thomas Jefferson University, Philadelphia, PA; and the University of Athens Medical School, Greece.
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26
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Morales-Ruiz V, Juárez-Vaquera VH, Rosetti-Sciutto M, Sánchez-Muñoz F, Adalid-Peralta L. Efficacy of intravenous immunoglobulin in autoimmune neurological diseases. Literature systematic review and meta-analysis. Autoimmun Rev 2021; 21:103019. [PMID: 34920107 DOI: 10.1016/j.autrev.2021.103019] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Accepted: 12/12/2021] [Indexed: 12/23/2022]
Abstract
BACKGROUND Corticosteroids are the first-line treatment for several common autoimmune neurological diseases. Other therapeutic approaches, including intravenous immunoglobulin (IVIg) and plasmapheresis, have shown mixed results in patient improvement. OBJECTIVE To compare the efficacy of IVIg administration with that of corticosteroids, plasmapheresis, and placebo in autoimmune neurological diseases like Guillain-Barré syndrome, myasthenia gravis, chronic inflammatory demyelinating polyneuropathy, optic neuritis, and multiple sclerosis. METHODS A systematic review was performed on the databases PubMed, MEDLINE, Embase, and Cochrane. Controlled, randomized studies comparing the efficacy of IVIg with placebo, plasmapheresis, and/or glucocorticoid administration were selected. Only studies reporting the number of patients who improved after treatment were included, irrespective of language or publication year. In total, 23 reports were included in the meta-analysis study. RESULTS Our meta-analysis showed a beneficial effect of IVIg administration on patient improvement over placebo (OR = 2.79, CI [95%] = 1.40-5.55, P = 0.01). Meanwhile, IVIg administration showed virtually identical effects to plasmapheresis (OR = 0.83, CI [95%] = 0.45-1.55, P < 0.01). Finally, no significant differences were found in the efficacy of IVIg and glucocorticoid administration (OR = 0.98, Cl [95%] = 0.58-1.68, P = 0.13). CONCLUSION IVIg can be regarded as a viable therapeutic approach, either as a first- or second-line therapy, and as an adjuvant therapy for autoimmune neurological diseases.
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Affiliation(s)
- Valeria Morales-Ruiz
- Unidad Periférica para el Estudio de la Neuroinflamación en Patologías Neurológicas del Instituto de Investigaciones Biomédicas de la UNAM en el Instituto Nacional de Neurología y Neurocirugía, Insurgentes Sur 3877, Col. La Fama, Ciudad de México 14269, Mexico; Posgrado en Ciencias Biológicas, Universidad Nacional Autónoma de México, Av. Ciudad Universitaria 3000, Coyoacán, Ciudad de México 04510, Mexico
| | - Víctor Hugo Juárez-Vaquera
- Unidad Periférica para el Estudio de la Neuroinflamación en Patologías Neurológicas del Instituto de Investigaciones Biomédicas de la UNAM en el Instituto Nacional de Neurología y Neurocirugía, Insurgentes Sur 3877, Col. La Fama, Ciudad de México 14269, Mexico
| | - Marcos Rosetti-Sciutto
- Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad de México 04510, Mexico; Instituto Nacional de Psiquiatría Ramón de la Fuente Muñiz, México-Xochimilco 101, Col. Huipulco, Ciudad de México 14370, Mexico
| | - Fausto Sánchez-Muñoz
- Instituto Nacional de Cardiología Ignacio Chávez, Juan Badiano 1, Col. Belisario Domínguez Secc. 16, Ciudad de México 14080, Mexico
| | - Laura Adalid-Peralta
- Unidad Periférica para el Estudio de la Neuroinflamación en Patologías Neurológicas del Instituto de Investigaciones Biomédicas de la UNAM en el Instituto Nacional de Neurología y Neurocirugía, Insurgentes Sur 3877, Col. La Fama, Ciudad de México 14269, Mexico; Instituto Nacional de Neurología y Neurocirugía, Insurgentes Sur 3877, Col. La Fama, Ciudad de México 14269, Mexico.
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Comparative Analysis of BIOCHIP Mosaic-Based Indirect Immunofluorescence with Enzyme-Linked Immunosorbent Assay for Diagnosing Myasthenia Gravis. Diagnostics (Basel) 2021; 11:diagnostics11112098. [PMID: 34829445 PMCID: PMC8619605 DOI: 10.3390/diagnostics11112098] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 11/04/2021] [Accepted: 11/10/2021] [Indexed: 11/17/2022] Open
Abstract
Background: The detection of anti-acetylcholine receptor (AChR) and anti-muscle-specific tyrosine kinase (MuSK) antibodies is useful in myasthenia gravis (MG) diagnosis and management. BIOCHIP mosaic-based indirect immunofluorescence is a novel analytical method, which employs the simultaneous detection of anti-AChR and anti-MuSK antibodies in a single miniature incubation field. In this study, we compare, for the first time, the BIOCHIP MG mosaic with conventional enzyme-linked immunosorbent assay (ELISA) in the diagnosis of MG. Methods: A total of 71 patients with MG diagnosis were included in the study. Anti-AChR and anti-MuSK antibodies were measured separately by two different ELISA and simultaneously by BIOCHIP. The results were then compared. Results: The overall concordance between ELISA and BIOCHIP for anti-AChR reactivity was 74%. Cohen’s kappa was 0.51 (95% CI 0.32–0.71), which corresponds to 90% of the maximum possible kappa (0.57), given the observed marginal frequencies. The overall concordance for anti-MuSK reactivity was 84%. Cohen’s kappa was 0.11 (95% CI 0.00–0.36), which corresponds to 41% of the maximum possible kappa (0.27). Conclusion: The overall concordance among assays is not optimal.
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28
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Dalakas MC. Update on Intravenous Immunoglobulin in Neurology: Modulating Neuro-autoimmunity, Evolving Factors on Efficacy and Dosing and Challenges on Stopping Chronic IVIg Therapy. Neurotherapeutics 2021; 18:2397-2418. [PMID: 34766257 PMCID: PMC8585501 DOI: 10.1007/s13311-021-01108-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/11/2021] [Indexed: 02/07/2023] Open
Abstract
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.
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Affiliation(s)
- Marinos C Dalakas
- Department of Neurology, Thomas Jefferson University, Philadelphia, PA, USA.
- Neuroimmunology Unit, Dept. of Pathophysiology, National and Kapodistrian University of Athens Medical School, Athens, Greece.
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Sindhu RK, Madaan P, Chandel P, Akter R, Adilakshmi G, Rahman MH. Therapeutic Approaches for the Management of Autoimmune Disorders via Gene Therapy: Prospects, Challenges, and Opportunities. Curr Gene Ther 2021; 22:245-261. [PMID: 34530709 DOI: 10.2174/1566523221666210916113609] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 07/05/2021] [Accepted: 06/24/2021] [Indexed: 11/22/2022]
Abstract
BACKGROUND Autoimmune diseases are the diseases that result due to the overactive immune response, and comprise systemic autoimmune diseases like rheumatoid arthritis (RA), sjӧgren's syndrome (SS), and organ-specific autoimmune diseases like type-1 diabetes mellitus (T1DM), myasthenia gravis (MG), and inflammatory bowel disease (IBD). Currently, there is no long-term cure; but, several treatments exist which retard the evolution of the disease, embracing gene therapy, which has been scrutinized to hold immense aptitude for the management of autoimmune diseases. OBJECTIVE The review highlights the pathogenic mechanisms and genes liable for the development of autoimmune diseases, namely T1DM, type-2 diabetes mellitus (T2DM), RA, SS, IBD, and MG. Furthermore, the review focuses on investigating the outcomes of delivering the corrective genes with their specific viral vectors in various animal models experiencing these diseases to determine the effectiveness of gene therapy. METHODS Numerous review and research articles emphasizing the tremendous potential of gene therapy in the management of autoimmune diseases were procured from PubMed, MEDLINE, Frontier, and other databases and thoroughly studied for writing this review article. RESULTS The various animal models that experienced treatment with gene therapy have displayed regulation in the levels of proinflammatory cytokines, infiltration of lymphocytes, manifestations associated with autoimmune diseases, and maintained equilibrium in the immune response, thereby hinder the progression of autoimmune diseases. CONCLUSION Gene therapy has revealed prodigious aptitude in the management of autoimmune diseases in various animal studies, but further investigation is essential to combat the limitations associated with it and before employing it on humans.
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Affiliation(s)
- Rakesh K Sindhu
- Chitkara College of Pharmacy, Chitkara University, Punjab. India
| | - Piyush Madaan
- Chitkara College of Pharmacy, Chitkara University, Punjab. India
| | - Parteek Chandel
- Chitkara College of Pharmacy, Chitkara University, Punjab. India
| | - Rokeya Akter
- Department of Pharmacy, Jagannath University, Sadarghat, Dhaka-1100. Bangladesh
| | - G Adilakshmi
- Department of PhysicxVikramaSimahpuri University, P.G. Centre, kavil-524201, Andhra Pradesh. India
| | - Md Habibur Rahman
- Department of Pharmacy, Southeast University, Banani, Dhaka-1213. Bangladesh
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Menon D, Urra Pincheira A, Bril V. Emerging drugs for the treatment of myasthenia gravis. Expert Opin Emerg Drugs 2021; 26:259-270. [PMID: 34228579 DOI: 10.1080/14728214.2021.1952982] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Introduction: Advances in understanding the immune pathomechanisms in myasthenia gravis (MG) allow for the development of novel targeted immune therapies. By working at specific points in the immunopathogenesis, these agents have the potential to provide rapid and efficacious responses compared to conventional immunosuppressive therapy (IST), addressing unmet needs and consequently are a research priority.Areas covered: This paper reviews the advances in MG treatment modalities with their scientific rationale. A search of clinicaltrials.gov and a literature search of PubMed from January 2015 to the end of June 2021 was done using the search terms: MG, treatment, immune targets to obtain information on recent developments of complement inhibitors, FcRn receptor inhibitors, direct and indirect B cell inhibitors, CAR and CAAR- T cell therapy, and hematopoietic stem cell transplantation. Specific agents in various phases of clinical development, evidence from ongoing trials and potential roadblocks are examined.Expert opinion: Despite several promising novel agents, existing data as to the timing of initiation and duration of treatment, long-term safety profile and utility in certain patient subsets are limited and require further research. Despite these considerations, the future of MG treatment is transitioning from broad-spectrum IST toward precise, target-driven and personalized immunotherapy.
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Affiliation(s)
- Deepak Menon
- Department of Medicine, Ellen & Martin Prosserman Centre for Neuromuscular Diseases, University Health Network, University of Toronto, Toronto, Canada
| | - Alejandra Urra Pincheira
- Department of Medicine, Ellen & Martin Prosserman Centre for Neuromuscular Diseases, University Health Network, University of Toronto, Toronto, Canada
| | - Vera Bril
- Department of Medicine, Ellen & Martin Prosserman Centre for Neuromuscular Diseases, University Health Network, University of Toronto, Toronto, Canada
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Cacciaguerra L, Tortorella P, Rocca MA, Filippi M. Targeting Neuromyelitis Optica Pathogenesis: Results from Randomized Controlled Trials of Biologics. Neurotherapeutics 2021; 18:1623-1636. [PMID: 33909234 PMCID: PMC8608970 DOI: 10.1007/s13311-021-01055-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/31/2021] [Indexed: 02/04/2023] Open
Abstract
Advances in neuromyelitis optica spectrum disorder pathogenesis have allowed the development of targeted drugs. These treatments act on core elements of the disease, including the pro-inflammatory IL-6 pathway (tocilizumab and satralizumab), B cells (rituximab and inebilizumab), and complement (eculizumab). According to recent phase II-III trials, biologics significantly reduced the risk of relapses in aquaporin-4-seropositive patients, whereas results were less striking in the small cohorts of aquaporin-4-seronegative patients. Most adverse events were mild to moderate, with systemic symptoms (headache, arthralgia) or infections (upper respiratory and urinary tracts) being most commonly reported.
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Affiliation(s)
- Laura Cacciaguerra
- Neuroimaging Research Unit, Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy
- Neurology Unit, IRCCS San Raffaele Scientific Institute, Milan, Italy
- Vita-Salute San Raffaele University, Milan, Italy
| | | | - Maria A Rocca
- Neuroimaging Research Unit, Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy
- Neurology Unit, IRCCS San Raffaele Scientific Institute, Milan, Italy
- Vita-Salute San Raffaele University, Milan, Italy
| | - Massimo Filippi
- Neuroimaging Research Unit, Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy.
- Neurology Unit, IRCCS San Raffaele Scientific Institute, Milan, Italy.
- Vita-Salute San Raffaele University, Milan, Italy.
- Neurorehabilitation Unit, IRCCS San Raffaele Scientific Institute, Milan, Italy.
- Neurophysiology Service, IRCCS San Raffaele Scientific Institute, Milan, Italy.
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Evoli A, Spagni G, Monte G, Damato V. Heterogeneity in myasthenia gravis: considerations for disease management. Expert Rev Clin Immunol 2021; 17:761-771. [PMID: 34043932 DOI: 10.1080/1744666x.2021.1936500] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Introduction: Myasthenia gravis is a rare disease of the neuromuscular junction and a prototype of B cell-driven immunopathology. Pathogenic antibodies target post-synaptic transmembrane proteins, most commonly the nicotinic acetylcholine receptor and the muscle-specific tyrosine kinase, inducing end-plate alterations and neuromuscular transmission impairment. Several clinical subtypes are distinct on the basis of associated antibodies, age at symptom onset, thymus pathology, genetic factors, and weakness distribution. These subtypes have distinct pathogenesis that can account for different responses to treatment. Conventional therapy is based on the use of symptomatic agents, steroids, immunosuppressants and thymectomy. Of late, biologics have emerged as effective therapeutic options.Areas covered: In this review, we will discuss the management of myasthenia gravis in relation to its phenotypic and biological heterogeneity, in the light of recent advances in the disease immunopathology, new diagnostic tools, and results of clinical trialsExpert opinion: Clinical management is shaped on serological subtype, and patient age at onset, lifestyle and comorbidities, balancing therapeutic needs and safety. Although reliable biomarkers predictive of clinical and biologic outcome are still lacking, recent developments promise a more effective and safe treatment. Disease subtyping according to serological testing and immunopathology is crucial to the appropriateness of clinical management.
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Affiliation(s)
- Amelia Evoli
- Dipartimento di Neuroscienze, Università Cattolica Del Sacro Cuore, Rome, Italy.,Unità Operativa Complessa di Neurologia, Fondazione Policlinico Universitario "A. Gemelli" IRCCS, Rome, Italy
| | - Gregorio Spagni
- Dipartimento di Neuroscienze, Università Cattolica Del Sacro Cuore, Rome, Italy
| | - Gabriele Monte
- Dipartimento di Neuroscienze, Università Cattolica Del Sacro Cuore, Rome, Italy
| | - Valentina Damato
- Dipartimento di Neuroscienze, Università Cattolica Del Sacro Cuore, Rome, Italy
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Fc-Receptor Targeted Therapies for the Treatment of Myasthenia gravis. Int J Mol Sci 2021; 22:ijms22115755. [PMID: 34071155 PMCID: PMC8198115 DOI: 10.3390/ijms22115755] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 05/24/2021] [Accepted: 05/25/2021] [Indexed: 12/16/2022] Open
Abstract
Myasthenia gravis (MG) is an autoimmune disease in which immunoglobulin G (IgG) antibodies (Abs) bind to acetylcholine receptors (AChR) or to functionally related molecules in the postsynaptic membrane at the neuromuscular junction. IgG crystallizable fragment (Fc)-mediated effector functions, such as antibody-dependent complement deposition, contribute to disease development and progression. Despite progress in understanding Ab-mediated disease mechanisms, immunotherapy of MG remained rather unspecific with corticosteroids and maintenance with immunosuppressants as first choice drugs for most patients. More specific therapeutic IgG Fc-based platforms that reduce serum half-life or effector functions of pathogenic MG-related Abs are currently being developed, tested in clinical trials or have recently been successfully translated into the clinic. In this review, we illustrate mechanisms of action and clinical efficacies of emerging Fc-mediated therapeutics such as neonatal Fc receptor (FcRn)-targeting agents. Furthermore, we evaluate prospects of therapies targeting classical Fc receptors that have shown promising therapeutic efficacy in other antibody-mediated conditions. Increased availability of Fc- and Fc receptor-targeting biologics might foster the development of personalized immunotherapies with the potential to induce sustained disease remission in patients with MG.
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Shehata GA, Lord KC, Grudzinski MC, Elsayed M, Abdelnaby R, Elshabrawy HA. Neurological Complications of COVID-19: Underlying Mechanisms and Management. Int J Mol Sci 2021; 22:4081. [PMID: 33920904 PMCID: PMC8071289 DOI: 10.3390/ijms22084081] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Revised: 04/10/2021] [Accepted: 04/13/2021] [Indexed: 02/06/2023] Open
Abstract
COVID-19 is a severe respiratory disease caused by the newly identified human coronavirus (HCoV) Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2). The virus was discovered in December 2019, and in March 2020, the disease was declared a global pandemic by the World Health Organization (WHO) due to a high number of cases. Although SARS-CoV-2 primarily affects the respiratory system, several studies have reported neurological complications in COVID-19 patients. Headache, dizziness, loss of taste and smell, encephalitis, encephalopathy, and cerebrovascular diseases are the most common neurological complications that are associated with COVID-19. In addition, seizures, neuromuscular junctions' disorders, and Guillain-Barré syndrome were reported as complications of COVID-19, as well as neurodegenerative and demyelinating disorders. However, the management of these conditions remains a challenge. In this review, we discuss the prevalence, pathogenesis, and mechanisms of these neurological sequelae that are secondary to SARS-CoV-2 infection. We aim to update neurologists and healthcare workers on the possible neurological complications associated with COVID-19 and the management of these disease conditions.
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Affiliation(s)
- Ghaydaa A. Shehata
- Department of Neurology and Psychiatry, Assiut University Hospitals, Assiut 71511, Egypt;
| | - Kevin C. Lord
- Department of Physiology and Pharmacology, College of Osteopathic Medicine, Sam Houston State University, Conroe, TX 77304, USA;
| | | | - Mohamed Elsayed
- Department of Psychiatry and Psychotherapy III, University of Ulm, Leimgrubenweg 12-14, 89075 Ulm, Germany;
| | - Ramy Abdelnaby
- Department of Neurology, RWTH Aachen University, Pauwelsstraße 30, 52074 Aachen, Germany;
| | - Hatem A. Elshabrawy
- Department of Molecular and Cellular Biology, College of Osteopathic Medicine, Sam Houston State University, Conroe, TX 77304, USA
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Abstract
ABSTRACT This update covers recommendations for myasthenia gravis (MG) in patients with coronavirus 2019 disease as well as reports of the clinical features of patients with MG and coronavirus 2019. Updated advisory committee recommendations for the use of thymectomy in generalized MG are also provided. Other MG topics include lipoprotein receptor-4 and agrin antibody associations, factors influencing conversion of ocular to generalized MG, the use of rituximab for more recent onset disease, immunoglobulins for maintenance therapy, and fatigue and depression.
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Affiliation(s)
- David Lacomis
- Departments of Neurology and Pathology (Neuropathology), University of Pittsburgh School of Medicine, Pittsburgh, PA; and
| | - Gil I Wolfe
- Department of Neurology, University at Buffalo Jacobs School of Medicine and Biomedical Sciences/SUNY, Buffalo, NY
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Dalakas MC, Spaeth PJ. The importance of FcRn in neuro-immunotherapies: From IgG catabolism, FCGRT gene polymorphisms, IVIg dosing and efficiency to specific FcRn inhibitors. Ther Adv Neurol Disord 2021; 14:1756286421997381. [PMID: 33717213 PMCID: PMC7917847 DOI: 10.1177/1756286421997381] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 02/03/2021] [Indexed: 11/25/2022] Open
Abstract
The neonatal Fc receptor (FcRn) binds endogenous IgG and protects it from lysosomal degradation by transporting it back to the cell surface to re-enter the circulation, extending the serum IgG life span. FcRn plays a role in the function of IVIg because the supraphysiological IgG levels derived from IVIg administrations saturate the FcRn allowing the endogenous IgG to be degraded, instead of being recycled, resulting in high levels of infused IgG ensuring IVIg efficiency. New data in myasthenia gravis patients suggest that the that the Variable Number of Tandem 3/2 (VNTR3/2) polymorphisms in FCGRT, the gene that encodes FcRn, may affect the duration of infused IgG in the circulation and IVIg effectiveness. This review addresses these implications in the context of whether the FCGRT genotype, by affecting the half-life of IVIg, may also play a role in up to 30% of patients with autoimmune neurological diseases, such as Guillain–Barré syndrome, CIDP or Multifocal Motor Neuropathy, who did not respond to IVIg in controlled trials. The concern is of practical significance because in such patient subsets super-high IVIg doses may be needed to achieve high IgG levels and ensure efficacy. Whether FCGRT polymorphisms affect the efficacy of other therapeutic monoclonal antibodies by influencing their distribution clearance and pharmacokinetics, explaining their variable effectiveness, is also addressed. Finally, the very promising effect of monoclonal antibodies that inhibit FcRn, such as efgartigimod, rozanolixizumab and nipocalimab, in treating antibody-mediated neurological diseases is discussed along with their efficacy in the IgG4 subclass of pathogenic antibodies and their role in the blood–brain barrier endothelium, that abundantly expresses FcRn.
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Affiliation(s)
- Marinos C Dalakas
- Thomas Jefferson University, 900 Walnut Street, Philadelphia, PA 19107, USA
| | - Peter J Spaeth
- Institute of Pharmacology, University of Bern, Bern, Switzerland
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Su S, Liu Q, Zhang X, Wen X, Lei L, Shen F, Fan Z, Duo J, Lu Y, Di L, Wang M, Chen H, Zhu W, Xu M, Wang S, Da Y. VNTR2/VNTR3 genotype in the FCGRT gene is associated with reduced effectiveness of intravenous immunoglobulin in patients with myasthenia gravis. Ther Adv Neurol Disord 2021; 14:1756286420986747. [PMID: 33552238 PMCID: PMC7844454 DOI: 10.1177/1756286420986747] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 12/11/2020] [Indexed: 12/19/2022] Open
Abstract
Background: Intravenous immunoglobulin (IVIG) has been commonly used to treat myasthenia gravis exacerbation, but is still ineffective in nearly 30% of patients. A variable number of tandem repeat (VNTR) polymorphism in the FCGRT gene has been found to reduce the efficiency of IgG biologics. However, whether the polymorphism influences the efficacy of IVIG in generalized myasthenia gravis (MG) patients with exacerbations remains unknown. Methods: The distribution of VNTR genotypes was analyzed in 334 patients with MG. Varied VNTR alleles were determined by capillary electrophoresis and confirmed by Sanger sequencing. Information of endogenous IgG levels were collected in patients without previous immunotherapy (n = 26). Medical records of patients who received IVIG therapy were retrospectively analyzed for therapeutic outcomes of IVIG treatment (n = 61). Patients whose Activities of Daily Living scores decreased by 2 or more points on day 14 were considered responders to the treatment. Results: The VNTR3/3 and VNTR2/3 genotypes were detected in 96.7% (323/334) and 3.4% (11/334) patients, respectively. Patients with VNTR2/3 heterozygosity had lower endogenous IgG levels than those with VNTR3/3 homozygosity (9.81 ± 2.61 g/L versus 12.41 ± 2.45g/L, p = 0.016). The response rate of IVIG therapy was 78.7% (48/61). All responders and nine non-responders were VNTR3/3 homozygotes, whereas all the patients with VNTR2/3 genotypes were non-responders (n = 4). In patients who took IVIG treatments, endogenous IgG levels were significantly lower in non-responders compared with responders (12.93 ± 2.24 g/L versus 8.85 ± 2.69 g/L, p = 0.006), especially in VNTR2/3 heterozygotes (7.86 ± 1.78 g/L, p = 0.001). Conclusion: The VNTR2/3 genotype could influence endogenous IgG levels and serve as a predictive marker for poor responses to IVIG in MG patients.
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Affiliation(s)
- Shengyao Su
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Qing Liu
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Chang Chun Street, Beijing, China
| | - Xueping Zhang
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Chang Chun Street, Beijing, China
| | - Xinmei Wen
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Lin Lei
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Faxiu Shen
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Zhirong Fan
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Jianying Duo
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Yan Lu
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Li Di
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Min Wang
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Hai Chen
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Wenjia Zhu
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Min Xu
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Suobin Wang
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Yuwei Da
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Chang Chun Street, Beijing 100053, China
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Dalakas MC, Alexopoulos H, Spaeth PJ. Complement in neurological disorders and emerging complement-targeted therapeutics. Nat Rev Neurol 2020; 16:601-617. [PMID: 33005040 PMCID: PMC7528717 DOI: 10.1038/s41582-020-0400-0] [Citation(s) in RCA: 134] [Impact Index Per Article: 33.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/07/2020] [Indexed: 12/30/2022]
Abstract
The complement system consists of a network of plasma and membrane proteins that modulate tissue homeostasis and contribute to immune surveillance by interacting with the innate and adaptive immune systems. Dysregulation, impairment or inadvertent activation of complement components contribute to the pathogenesis of some autoimmune neurological disorders and could even contribute to neurodegenerative diseases. In this Review, we summarize current knowledge about the main functions of the complement pathways and the involvement of complement in neurological disorders. We describe the complex network of complement proteins that target muscle, the neuromuscular junction, peripheral nerves, the spinal cord or the brain and discuss the autoimmune mechanisms of complement-mediated myopathies, myasthenia, peripheral neuropathies, neuromyelitis and other CNS disorders. We also consider the emerging role of complement in some neurodegenerative diseases, such as Alzheimer disease, amyotrophic lateral sclerosis and even schizophrenia. Finally, we provide an overview of the latest complement-targeted immunotherapies including monoclonal antibodies, fusion proteins and peptidomimetics that have been approved, that are undergoing phase I–III clinical trials or that show promise for the treatment of neurological conditions that respond poorly to existing immunotherapies. In this Review, Dalakas et al. discuss the complement system, the role it plays in autoimmune neurological disease and neurodegenerative disease, and provide an overview of the latest therapeutics that target complement and that can be used for or have potential in neurological disorders. Complement has an important physiological role in host immune defences and tissue remodelling. The physiological role of complement extends to the regulation of synaptic development. Complement has a key pathophysiological role in autoimmune neurological diseases and mediates the actions of pathogenic autoantibodies, such as acetylcholine receptor antibodies and aquaporin 4 antibodies. For some autoimmune neurological diseases, such as myasthenia gravis and neuromyelitis optica spectrum disorders, approved complement-targeted treatments are now available. Complement also seems to be of pathogenic relevance in neurodegenerative diseases such as Alzheimer disease, in which innate immune-driven inflammation is receiving increasing attention. The field of complement-targeted therapeutics is rapidly expanding, with several FDA-approved agents and others currently in phase II and phase III clinical trials.
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Affiliation(s)
- Marinos C Dalakas
- Department of Neurology, Thomas Jefferson University, Philadelphia, PA, USA. .,Neuroimmunology Unit, Department of Pathophysiology, Faculty of Medicine, National and Kapodistrian University of Athens, Athens, Greece.
| | - Harry Alexopoulos
- Neuroimmunology Unit, Department of Pathophysiology, Faculty of Medicine, National and Kapodistrian University of Athens, Athens, Greece
| | - Peter J Spaeth
- Institute of Pharmacology, University of Bern, Bern, Switzerland
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