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Bouwman HB, Guchelaar HJ. The efficacy and safety of eculizumab in patients and the role of C5 polymorphisms. Drug Discov Today 2024; 29:104134. [PMID: 39111540 DOI: 10.1016/j.drudis.2024.104134] [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: 03/14/2024] [Revised: 07/11/2024] [Accepted: 07/31/2024] [Indexed: 08/13/2024]
Abstract
Eculizumab is an orphan drug with indications for extremely rare autoimmune disorders. It is primarily prescribed for use in patients with paroxysmal nocturnal hemoglobinuria and atypical hemolytic uremic syndrome; but is also highly effective in the treatment of myasthenia gravis, among others. By binding to the C5 protein in the complement system, eculizumab effectively inhibits cellular hemolysis and autoimmune reactions. Despite this effective treatment, some patients reported no improvement in symptoms. Genetic sequencing revealed three distinct C5 mutations in the non-responders and these polymorphisms appeared to be most prevalent among Japanese, Korean and African populations. Here, we present an overview of the current and potential future applications of eculizumab, as well as the disadvantages of eculizumab treatment in patients with C5 polymorphisms.
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Affiliation(s)
| | - Henk-Jan Guchelaar
- Clinical Pharmacy and Toxicology, Leiden University Medical Center, PO Box 9600, 2300 RC Leiden, the Netherlands.
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2
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Song J, Huan X, Chen Y, Luo Y, Zhong H, Wang Y, Yang L, Xi C, Yang Y, Xi J, Zheng J, Wu Z, Zhao C, Luo S. The safety and efficacy profile of eculizumab in myasthenic crisis: a prospective small case series. Ther Adv Neurol Disord 2024; 17:17562864241261602. [PMID: 39072008 PMCID: PMC11282533 DOI: 10.1177/17562864241261602] [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: 01/03/2024] [Accepted: 05/27/2024] [Indexed: 07/30/2024] Open
Abstract
Eculizumab has improved recovery from ventilatory support in myasthenic crisis (MC) cases. However, the safety and efficacy profiles from prospective studies are still lacking. This study aimed to explore eculizumab's safety and efficacy in a prospective case series of patients with refractory MC. We followed a series of anti-acetylcholine receptor (AChR) antibody-positive myasthenia gravis (MG) patients who received eculizumab as an add-on therapy for 12 weeks during MC to facilitate the weaning process and reduced disease activity. Serum anti-AChR antibodies and peripheral immune molecules associated with the complement pathway were evaluated before and after eculizumab administration. Compared to the baseline Myasthenia Gravis Foundation of America (MGFA)-quantitative MG test (QMG) scores (22.25 ± 4.92) and MG-activities of daily living (MG-ADL; 18.25 ± 2.5) scores at crisis, improvements were observed from 4 weeks (14.5 ± 10.47 and 7.5 ± 7.59, respectively) through 12 weeks (7.5 ± 5.74 and 2.25 ± 3.86, respectively) post-treatment. Muscle strength consistently improved across ocular, bulbar, respiratory, and limb/gross domain groups. One patient died of cardiac failure at 16 weeks. Three cases remained in remission at 24 weeks, with a mean QMG score of 2.67 ± 2.89 and ADL score of 0.33 ± 0.58. No significant side effects were reported. Serum CH50 and soluble C5b-9 levels significantly declined, while there were no significant changes in serum anti-AChR antibody levels, C1q, C5a levels, or peripheral lymphocyte proportions. Eculizumab was well tolerated and showed efficacy in this case series. Large prospective cohort studies with extended follow-up periods are needed to further explore the safety and efficacy profile in real-world practice.
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Affiliation(s)
- Jie Song
- Huashan Rare Disease Center and Department of Neurology, Huashan Hospital, Shanghai Medical College, National Center for Neurological Disorders, Fudan University, Shanghai, China
| | - Xiao Huan
- Huashan Rare Disease Center and Department of Neurology, Huashan Hospital, Shanghai Medical College, National Center for Neurological Disorders, Fudan University, Shanghai, China
| | - Yuanyi Chen
- Huashan Rare Disease Center and Department of Neurology, Huashan Hospital, Shanghai Medical College, National Center for Neurological Disorders, Fudan University, Shanghai, China
| | - Yeting Luo
- Department of Neurology, Ganzhou People’s Hospital, Nanchang University, Nanchang, Jiangxi, China
| | - Huahua Zhong
- Huashan Rare Disease Center and Department of Neurology, Huashan Hospital, Shanghai Medical College, National Center for Neurological Disorders, Fudan University, Shanghai, China
| | - Yuan Wang
- Department of Blood Transfusion, Huashan Hospital, Fudan University, Shanghai, China
| | - Lei Yang
- Department of Neurosurgery & Neurocritical care, Huashan Hospital Fudan University, Shanghai, China
| | - Caihua Xi
- Department of Neurosurgery & Neurocritical care, Huashan Hospital Fudan University, Shanghai, China
| | - Yu Yang
- Department of Thoracic Surgery, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Jianying Xi
- Huashan Rare Disease Center and Department of Neurology, Huashan Hospital, Shanghai Medical College, National Center for Neurological Disorders, Fudan University, Shanghai, China
| | - Jianming Zheng
- Department of Infectious Diseases, Huashan Hospital, National Medical Center for Infectious Diseases, Fudan University, Shanghai, China
| | - Zongtai Wu
- Faculty of Biology, University of Cambridge, Cambridge, UK
| | - Chongbo Zhao
- Department of Neurology, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Sushan Luo
- Department of Neurology, Huashan Hospital, Fudan University, Shanghai 200040, China
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Mantegazza R, Saccà F, Antonini G, Bonifati DM, Evoli A, Habetswallner F, Liguori R, Pegoraro E, Rodolico C, Schenone A, Sgarzi M, Pappagallo G. Therapeutic challenges and unmet needs in the management of myasthenia gravis: an Italian expert opinion. Neurol Sci 2024:10.1007/s10072-024-07577-7. [PMID: 38967883 DOI: 10.1007/s10072-024-07577-7] [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: 12/27/2023] [Accepted: 05/03/2024] [Indexed: 07/06/2024]
Abstract
Myasthenia gravis (MG) is a rare, autoimmune, neurological disorder. Most MG patients have autoantibodies against acetylcholine receptors (AChRs). Some have autoantibodies against muscle-specific tyrosine kinase (MuSK) or lipoprotein-receptor-related protein 4 (LRP4), and some are seronegative. Standard of care, which includes anti-cholinesterase drugs, thymectomy, corticosteroids (CS), and off-label use of non-steroidal immunosuppressive drugs (NSISTs), is bounded by potential side effects and limited efficacy in refractory generalized MG (gMG) patients. This highlights the need for new therapeutic approaches for MG. Eculizumab, a monoclonal antibody that inhibits the complement system, has been recently approved in Italy for refractory gMG. A panel of 11 experts met to discuss unmet therapeutic needs in the acute and chronic phases of the disease, as well as the standard of care for refractory patients. Survival was emphasized as an acute phase outcome. In the chronic phase, persistent remission and early recognition of exacerbations to prevent myasthenic crisis and respiratory failure were considered crucial. Refractory patients require treatments with fast onset of action, improved tolerability, and the ability to slow disease progression and increase life expectancy. The Panel agreed that eculizumab would presumably meet the therapeutic needs of many refractory gMG patients. The panel concluded that the unmet needs of current standard of care treatments for gMG are significant. Evaluating new therapeutic options accurately is essential to find the best balance between efficacy and tolerability for each patient. Collecting real-world data on novel molecules in routine clinical practice is necessary to address unmet needs.
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Affiliation(s)
- Renato Mantegazza
- Neuroimmunology and Neuromuscular Diseases Unit, IRCCS Foundation Carlo Besta Neurological Institute, Milan, Italy.
| | - Francesco Saccà
- NSRO Department, Federico II University of Naples, Naples, Italy
| | - Giovanni Antonini
- Department of Neurosciences, Mental Health and Sensory Organs (NESMOS), Sapienza University of Rome, Rome, Italy
| | - Domenico Marco Bonifati
- Neurology Unit, Cerebro-Cardiovascular Department, Ca' Foncello Hospital Treviso, Piazzale Ospedale 1, 31100, Treviso, Italy
| | - Amelia Evoli
- Neuroscience Department, Facolta Di Medicina E Chirurgia, Università Cattolica del Sacro Cuore, Rome, Italy
- Neurology Institute, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Rome, Italy
| | | | - Rocco Liguori
- Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, Bologna, Italy
- IRCCS Istituto Delle Scienze Neurologiche Di Bologna, UOC Clinica Neurologica, Bologna, Italy
| | | | - Carmelo Rodolico
- Department of Clinical and Experimental Medicine, University of Messina, Messina, Italy
| | - Angelo Schenone
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetic and Maternal and Infantile Sciences (DINOGMI), University and IRCCS San Martino Hospital, Genoa, Italy
| | - Manlio Sgarzi
- Department of Neurology, Papa Giovanni XXIII Hospital, Piazza OMS 1, 24127, Bergamo, Italy
| | - Giovanni Pappagallo
- School of Clinical Methodology, IRCCS "Sacred Heart - Don Calabria", Negrar Di Valpolicella, Italy
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Cavalcante P, Mantegazza R, Antozzi C. Targeting autoimmune mechanisms by precision medicine in Myasthenia Gravis. Front Immunol 2024; 15:1404191. [PMID: 38903526 PMCID: PMC11187261 DOI: 10.3389/fimmu.2024.1404191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Accepted: 05/24/2024] [Indexed: 06/22/2024] Open
Abstract
Myasthenia Gravis (MG) is a chronic disabling autoimmune disease caused by autoantibodies to the neuromuscular junction (NMJ), characterized clinically by fluctuating weakness and early fatigability of ocular, skeletal and bulbar muscles. Despite being commonly considered a prototypic autoimmune disorder, MG is a complex and heterogeneous condition, presenting with variable clinical phenotypes, likely due to distinct pathophysiological settings related with different immunoreactivities, symptoms' distribution, disease severity, age at onset, thymic histopathology and response to therapies. Current treatment of MG based on international consensus guidelines allows to effectively control symptoms, but most patients do not reach complete stable remission and require life-long immunosuppressive (IS) therapies. Moreover, a proportion of them is refractory to conventional IS treatment, highlighting the need for more specific and tailored strategies. Precision medicine is a new frontier of medicine that promises to greatly increase therapeutic success in several diseases, including autoimmune conditions. In MG, B cell activation, antibody recycling and NMJ damage by the complement system are crucial mechanisms, and their targeting by innovative biological drugs has been proven to be effective and safe in clinical trials. The switch from conventional IS to novel precision medicine approaches based on these drugs could prospectively and significantly improve MG care. In this review, we provide an overview of key immunopathogenetic processes underlying MG, and discuss on emerging biological drugs targeting them. We also discuss on future direction of research to address the need for patients' stratification in endotypes according with genetic and molecular biomarkers for successful clinical decision making within precision medicine workflow.
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Affiliation(s)
- Paola Cavalcante
- Neurology 4 – Neuroimmunology and Neuromuscular Diseases Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Renato Mantegazza
- Neurology 4 – Neuroimmunology and Neuromuscular Diseases Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Carlo Antozzi
- Neurology 4 – Neuroimmunology and Neuromuscular Diseases Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
- Immunotherapy and Apheresis Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
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Tokuyasu D, Suzuki S, Uzawa A, Nagane Y, Masuda M, Konno S, Kubota T, Samukawa M, Sugimoto T, Ishizuchi K, Oyama M, Yasuda M, Akamine H, Onishi Y, Suzuki Y, Kawaguchi N, Minami N, Kimura T, Takahashi MP, Murai H, Utsugisawa K. Real-world experience with eculizumab and switching to ravulizumab for generalized myasthenia gravis. Ann Clin Transl Neurol 2024; 11:1338-1346. [PMID: 38572524 DOI: 10.1002/acn3.52051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 03/01/2024] [Accepted: 03/10/2024] [Indexed: 04/05/2024] Open
Abstract
OBJECTIVE Eculizumab and ravulizumab are complement protein C5 inhibitors, showing efficacy and tolerability for patients with anti-acetylcholine receptor-positive (AChR+) generalized myasthenia gravis (gMG) in phase 3 clinical trials and subsequent analyses. The purpose of the present study was to evaluate the clinical significance of eculizumab and switching to ravulizumab for refractory AChR+ gMG patients in the real-world experience. METHODS Among the database of Japan MG registry survey 2021, we studied AChR+ gMG patients who received eculizumab. We also evaluated these patients who switched from eculizumab to ravulizumab. Responder was defined as an improvement of at least 3 points in MG-ADL. We performed a questionnaire of preference between eculizumab and ravulizumab. RESULTS Among 1,106 patients with AChR+ gMG, 36 patients (3%) received eculizumab (female 78%, mean age 56.0 years). Eculizumab was preferentially used in severe and refractory MG patients. The duration of eculizumab treatment was 35 months on average. MG-ADL improved from 9.4 ± 4.9 to 5.9 ± 5.1, and 25 (70%) of the 36 gMG patients were responders. Postintervention status was markedly improved after the eculizumab treatment. Of 13 patients who did not continue eculizumab, 6 showed insufficiencies. Early onset MG was most effective. However, 15 patients switching from eculizumab to ravulizumab kept favorable response and tolerability. Questionnaire surveys showed preference for ravulizumab over eculizumab. INTERPRETATION Eculizumab and switching to ravulizumab showed to be effective for refractory AChR+ gMG patients in clinical settings.
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Affiliation(s)
- Daiki Tokuyasu
- Department of Neurology, Keio University School of Medicine, Tokyo, Japan
| | - Shigeaki Suzuki
- Department of Neurology, Keio University School of Medicine, Tokyo, Japan
| | - Akiyuki Uzawa
- Department of Neurology, Graduate School of Medicine, Chiba University, Chiba, Japan
| | - Yuriko Nagane
- Department of Neurology, Hanamaki General Hospital, Hanamaki, Japan
| | - Masayuki Masuda
- Department of Neurology, Tokyo Medical University, Tokyo, Japan
| | - Shingo Konno
- Department of Neurology, Toho University Ohashi Medical Center, Tokyo, Japan
| | - Tomoya Kubota
- Department of Clinical Laboratory and Biomedical Sciences, Division of Health Sciences, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Makoto Samukawa
- Department of Neurology, Kindai University Faculty of Medicine, Sayama, Japan
| | - Takamichi Sugimoto
- Department of Clinical Neuroscience and Therapeutics, Hiroshima University, Hiroshima, Japan
| | - Kei Ishizuchi
- Department of Neurology, Keio University School of Medicine, Tokyo, Japan
| | - Munenori Oyama
- Department of Neurology, Keio University School of Medicine, Tokyo, Japan
| | - Manato Yasuda
- Department of Neurology, Graduate School of Medicine, Chiba University, Chiba, Japan
| | - Hiroyuki Akamine
- Department of Neurology, Graduate School of Medicine, Chiba University, Chiba, Japan
| | - Yosuke Onishi
- Department of Neurology, Graduate School of Medicine, Chiba University, Chiba, Japan
| | - Yasushi Suzuki
- Department of Neurology, National Hospital Organization Sendai Medical Center, Sendai, Japan
| | - Naoki Kawaguchi
- Department of Neurology, Neurology Chiba Clinic, Chiba, Japan
| | - Naoya Minami
- Department of Neurology, National Hospital Organization Hokkaido Medical Center, Sapporo, Japan
| | - Takashi Kimura
- Department of Neurology, Hyogo Medical University, Nishinomiya, Japan
| | - Masanori P Takahashi
- Department of Clinical Laboratory and Biomedical Sciences, Division of Health Sciences, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Hiroyuki Murai
- Department of Neurology, International University of Health and Welfare, Narita, Japan
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Li X, Chen J, Wang Y, Zheng S, Wan K, Liu X. Registered trials on novel therapies for myasthenia gravis: a cross-sectional study on ClinicalTrials.gov. Sci Rep 2024; 14:2067. [PMID: 38267496 PMCID: PMC10808105 DOI: 10.1038/s41598-024-52539-w] [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: 07/10/2023] [Accepted: 01/19/2024] [Indexed: 01/26/2024] Open
Abstract
Novel biologics in MG therapy research is on the rise. This research aimed to investigate the characteristics of registered trials on novel therapies for myasthenia gravis on ClinicalTrials.gov. This cross-sectional study used a descriptive approach to assess the features of the included trials on ClinicalTrials.gov. We found 62 registered trials from 2007 to 2023 on ClinicalTrials.gov. The results showed a yearly rise in the number of registered trials (r = 0.76, p < 0.001). Following 2017, more industry-sponsored trials were conducted (91.5% [43] vs. 60% [9], p = 0.009), fewer results were released (10.6% [5] vs. 60% [9], p = 0.001), and more trials entered phase 3 (67.4% [31] vs. 20% [2], p = 0.001). The most researched novel medications were neonatal Fc receptor inhibitors (51.2% [21]), complement inhibitors (39.0% [16]), and B cell depletors (14.6% [6]). According to the website's data, the neonatal Fc receptor inhibitors and complement inhibitors were effective in treating myasthenia gravis patients in three trials (NCT03315130, NCT03669588, and NCT00727194). This study provides valuable insights into the profile of registered trials on novel therapies for myasthenia gravis. More clinical studies are needed in the future to prove the value of its application.
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Affiliation(s)
- Xingyue Li
- Department of Neurology, Xiangyang No.1 People's Hospital, Hubei University of Medicine, Xiangyang, China
| | | | | | | | - Kun Wan
- Hubei University of Medicine, Shiyan, China
| | - Xiaodong Liu
- Department of Neurology, Taihe Hospital, Hubei University of Medicine, Shiyan, China.
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Zhou A, Ho S, Vickers A. Eculizumab in myasthenia gravis: A review. Saudi J Ophthalmol 2024; 38:34-40. [PMID: 38628404 PMCID: PMC11016999 DOI: 10.4103/sjopt.sjopt_74_23] [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: 03/31/2023] [Revised: 10/09/2023] [Accepted: 10/10/2023] [Indexed: 04/19/2024] Open
Abstract
Eculizumab, a monoclonal antibody against complement C5, is a novel therapy to treat refractory myasthenia gravis (MG). The present review was undertaken to study the role of eculizumab in MG. This includes the drug's mechanism, pharmacokinetics, clinical trial findings, tolerability, side effects, safety, dosage, administration, and cost. An English-language search for relevant items was undertaken using Embase and PubMed from 1946 to present. Clinical trial registries/databases and websites were also searched for relevant data. Keywords were eculizumab and MG. The present review found 103 articles after initial screening. Current data support eculizumab as an effective, safe, and tolerable drug in cases of refractory MG. However, its cost can prevent it from being widely accessible to a majority of the general population.
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Affiliation(s)
- Avery Zhou
- Kirk Kerkorian School of Medicine, Las Vegas, NV, USA
| | - Sabrina Ho
- Kirk Kerkorian School of Medicine, Las Vegas, NV, USA
| | - Aroucha Vickers
- Department of Neurology, Valley Hospital Medical Center, Las Vegas, NV, USA
- Department of Neuro-Ophthalmology, Las Vegas Neurology Center, Las Vegas, NV, USA
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Weidmayer SL, Gallagher G. Refractory generalized myasthenia gravis with myasthenic incomplete ophthalmoplegia successfully treated with eculizumab. Am J Ophthalmol Case Rep 2023; 32:101925. [PMID: 37711751 PMCID: PMC10498161 DOI: 10.1016/j.ajoc.2023.101925] [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: 03/21/2023] [Revised: 08/07/2023] [Accepted: 08/24/2023] [Indexed: 09/16/2023] Open
Abstract
Purpose This is a case of myasthenic incomplete ophthalmoplegia mimicking a partial cranial nerve 3 palsy both subjectively and objectively improving after treatment with eculizumab. Observations We chronicle a case of severe generalized myasthenia gravis including myasthenia masquerading as a partial cranial nerve 3 palsy, refractory to pyridostigmine, mycophenolate, prednisone, intravenous immunoglobulin and plasma exchange but responsive to eculizumab. Conclusions and importance This case demonstrates ocular and generalized myasthenia gravis refractory to several other therapies but amenable to eculizumab infusions, suggesting this medication may be of significant value in these difficult cases, and should be further explored for refractory ocular myasthenia gravis.
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Affiliation(s)
- Sara L. Weidmayer
- LTC Charles S. Kettles VA Medical Center, VA Ann Arbor Healthcare System, 2215 Fuller Road, Ann Arbor, MI, United States
- WK Kellogg Eye Center, Department of Ophthalmology and Visual Sciences, University of Michigan, 1000 Wall Street, Ann Arbor, MI, United States
| | - Gary Gallagher
- Department of Neurology, University of Michigan, 1500 E. Medical Center Dr #1914, Ann Arbor, MI, United States
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9
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Gazzola M, Martinat C. Unlocking the Complexity of Neuromuscular Diseases: Insights from Human Pluripotent Stem Cell-Derived Neuromuscular Junctions. Int J Mol Sci 2023; 24:15291. [PMID: 37894969 PMCID: PMC10607237 DOI: 10.3390/ijms242015291] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Revised: 09/26/2023] [Accepted: 10/16/2023] [Indexed: 10/29/2023] Open
Abstract
Over the past 20 years, the use of pluripotent stem cells to mimic the complexities of the human neuromuscular junction has received much attention. Deciphering the key mechanisms underlying the establishment and maturation of this complex synapse has been driven by the dual goals of addressing developmental questions and gaining insight into neuromuscular disorders. This review aims to summarise the evolution and sophistication of in vitro neuromuscular junction models developed from the first differentiation of human embryonic stem cells into motor neurons to recent neuromuscular organoids. We also discuss the potential offered by these models to decipher different neuromuscular diseases characterised by defects in the presynaptic compartment, the neuromuscular junction, and the postsynaptic compartment. Finally, we discuss the emerging field that considers the use of these techniques in drug screening assay and the challenges they will face in the future.
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Affiliation(s)
- Morgan Gazzola
- INSERM U861, Institute for Stem Cell Therapy and Exploration of Monogenic Diseases, 91100 Corbeil-Essonnes, France;
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10
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Vanoli F, Mantegazza R. Current drug treatment of myasthenia gravis. Curr Opin Neurol 2023; 36:410-415. [PMID: 37678337 DOI: 10.1097/wco.0000000000001196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/09/2023]
Abstract
PURPOSE OF REVIEW Myasthenia Gravis (MG) is a rare neurological disorder affecting the neuromuscular junction. Clinical hallmarks are fatigability and weakness affecting the extraocular, axial, limb and/or respiratory muscles. Despite immunosuppressive treatment, mainly based on corticosteroids and nonsteroidal immunosuppressants, the burden of MG is still significant, both in terms of inadequate disease control and burdensome side effects. Driven by such limits, the past years have been characterized by an escalation of MG drug development, with novel molecules which now focuses on having a more targeted effect, with a higher safety and efficacy profile. RECENT FINDINGS As the pathogenic mechanism of MG are slowly being unravelled, new potential targets for treatments are being considered. This has led since 2017 to the Food and Drug Administration (FDA)-approval of three new drugs that either act by blocking the complement system (i.e., eculizumab and ravulizumab) or by blocking the neonatal Fc receptor thus preventing immunoglobulin recycling and reducing imunoglobulin G (IgG) antibodies (i.e., efgartigimod). Other drugs, with similar mechanism of action, are currently under review for approval. SUMMARY The repertoire of available and developmental therapies for MG is rapidly expanding, finally responding to the unmet need of a more targeted and effective therapeutic approach in MG.
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Affiliation(s)
- Fiammetta Vanoli
- Neuroimmunology and Neuromuscular Disease Department, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan
- Department of Human Neurosciences Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy
| | - Renato Mantegazza
- Neuroimmunology and Neuromuscular Disease Department, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan
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11
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Stennett A, Friston K, Harris CL, Wollman AJM, Bronowska AK, Madden KS. The case for complement component 5 as a target in neurodegenerative disease. Expert Opin Ther Targets 2023; 27:97-109. [PMID: 36786123 DOI: 10.1080/14728222.2023.2177532] [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: 02/15/2023]
Abstract
INTRODUCTION Complement-based drug discovery is undergoing a renaissance, empowered by new advances in structural biology, complement biology and drug development. Certain components of the complement pathway, particularly C1q and C3, have been extensively studied in the context of neurodegenerative disease, and established as key therapeutic targets. C5 also has huge therapeutic potential in this arena, with its druggability clearly demonstrated by the success of C5-inhibitor eculizumab. AREAS COVERED We will discuss the evidence supporting C5 as a target in neurodegenerative disease, along with the current progress in developing different classes of C5 inhibitors and the gaps in knowledge that will help progress in the field. EXPERT OPINION Validation of C5 as a therapeutic target for neurodegenerative disease would represent a major step forward for complement therapeutics research and has the potential to furnish disease-modifying drugs for millions of patients suffering worldwide. Key hurdles that need to be overcome for this to be achieved are understanding how C5a and C5b should be targeted to bring therapeutic benefit and demonstrating the ability to target C5 without creating vulnerability to infection in patients. This requires greater biological elucidation of its precise role in disease pathogenesis, supported by better chemical/biological tools.
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Affiliation(s)
- Amelia Stennett
- School of Natural and Environmental Sciences, Newcastle University, NE1 7RU, Newcastle-Upon-Tyne, UK
| | - Kallie Friston
- School of Natural and Environmental Sciences, Newcastle University, NE1 7RU, Newcastle-Upon-Tyne, UK
| | - Claire L Harris
- Faculty of Medical Sciences, Newcastle University, NE2 4HH, Newcastle-Upon-Tyne, UK
| | - Adam J M Wollman
- Faculty of Medical Sciences, Newcastle University, NE2 4HH, Newcastle-Upon-Tyne, UK
| | - Agnieszka K Bronowska
- School of Natural and Environmental Sciences, Newcastle University, NE1 7RU, Newcastle-Upon-Tyne, UK
| | - Katrina S Madden
- School of Natural and Environmental Sciences, Newcastle University, NE1 7RU, Newcastle-Upon-Tyne, UK.,Faculty of Medical Sciences, Newcastle University, NE2 4HH, Newcastle-Upon-Tyne, UK
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12
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Abstract
PURPOSE OF REVIEW This review summarizes recent insights into the immunopathogenesis of autoimmune myasthenia gravis (MG). Mechanistic understanding is presented according to MG disease subtypes and by leveraging the knowledge gained through the use of immunomodulating biological therapeutics. RECENT FINDINGS The past two years of research on MG have led to a more accurate definition of the mechanisms through which muscle-specific tyrosine kinase (MuSK) autoantibodies induce pathology. Novel insights have also emerged from the collection of stronger evidence on the pathogenic capacity of low-density lipoprotein receptor-related protein 4 autoantibodies. Clinical observations have revealed a new MG phenotype triggered by cancer immunotherapy, but the underlying immunobiology remains undetermined. From a therapeutic perspective, MG patients can now benefit from a wider spectrum of treatment options. Such therapies have uncovered profound differences in clinical responses between and within the acetylcholine receptor and MuSK MG subtypes. Diverse mechanisms of immunopathology between the two subtypes, as well as qualitative nuances in the autoantibody repertoire of each patient, likely underpin the variability in therapeutic outcomes. Although predictive biomarkers of clinical response are lacking, these observations have ignited the development of assays that might assist clinicians in the choice of specific therapeutic strategies. SUMMARY Recent advances in the understanding of autoantibody functionalities are bringing neuroimmunologists closer to a more detailed appreciation of the mechanisms that govern MG pathology. Future investigations on the immunological heterogeneity among MG patients will be key to developing effective, individually tailored therapies.
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Affiliation(s)
- Gianvito Masi
- Department of Neurology, Yale School of Medicine, New Haven, CT 06511 USA
- Department of Immunobiology, Yale School of Medicine, New Haven, CT 06511 USA
| | - Kevin C. O’Connor
- Department of Neurology, Yale School of Medicine, New Haven, CT 06511 USA
- Department of Immunobiology, Yale School of Medicine, New Haven, CT 06511 USA
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13
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Complement Activation Profile in Myasthenia Gravis Patients: Perspectives for Tailoring Anti-Complement Therapy. Biomedicines 2022; 10:biomedicines10061360. [PMID: 35740382 PMCID: PMC9220000 DOI: 10.3390/biomedicines10061360] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 06/01/2022] [Accepted: 06/06/2022] [Indexed: 12/03/2022] Open
Abstract
The complement system plays a key role in myasthenia gravis (MG). Anti-complement drugs are emerging as effective therapies to treat anti-acetylcholine receptor (AChR) antibody-positive MG patients, though their usage is still limited by the high costs. Here, we searched for plasma complement proteins as indicators of complement activation status in AChR-MG patients, and potential biomarkers for tailoring anti-complement therapy in MG. Plasma was collected from AChR-MG and MuSK-MG patients, and healthy controls. Multiplex immunoassays and ELISA were used to quantify a panel of complement components (C1Q, C2, C3, C4, C5, Factor B, Factor H, MBL, and properdin) and activation products (C4b, C3b, C5a, and C5b-9), of classical, alternative and lectin pathways. C2 and C5 levels were significantly reduced, and C3, C3b, and C5a increased, in plasma of AChR-MG, but not MuSK-MG, patients compared to controls. This protein profile was indicative of complement activation. We obtained sensitivity and specificity performance results suggesting plasma C2, C3, C3b, and C5 as biomarkers for AChR-MG. Our findings reveal a plasma complement “C2, C3, C5, C3b, and C5a” profile associated with AChR-MG to be further investigated as a biomarker of complement activation status in AChR-MG patients, opening new perspectives for tailoring of anti-complement therapies to improve the disease treatment.
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14
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Vanoli F, Mantegazza R. Antibody Therapies in Autoimmune Neuromuscular Junction Disorders: Approach to Myasthenic Crisis and Chronic Management. Neurotherapeutics 2022; 19:897-910. [PMID: 35165857 PMCID: PMC9294078 DOI: 10.1007/s13311-022-01181-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/02/2022] [Indexed: 02/06/2023] Open
Abstract
Myasthenia gravis (MG) is a neurological autoimmune disorder characterized by muscle weakness and fatigue. It is a B cell-mediated disease caused by pathogenic antibodies directed against various components of the neuromuscular junction (NMJ). Despite the wide range of adverse effects, current treatment is still based on non-specific immunosuppression, particularly on long-term steroid usage. The increasing knowledge regarding the pathogenic mechanisms of MG has however allowed to create more target-specific therapies. A very attractive therapeutic approach is currently offered by monoclonal antibodies (mAbs), given their ability to specifically and effectively target different immunopathological pathways, such as the complement cascade, B cell-related cluster of differentiation (CD) proteins, and the human neonatal Fc receptor (FcRn). Up to now, eculizumab, a C5-directed mAb, has been approved for the treatment of generalized MG (gMG) and efgartigimod, a FcRn inhibitor, has just been approved by the U.S. Food and Drug Administration for the treatment of anti-acetylcholine receptor (AChR) antibody positive gMG. Other mAbs are currently under investigation with encouraging preliminary results, further enriching the new range of therapeutic possibilities for MG. This review article provides an overview of the present status of mAb-based therapies for MG, which offer an exciting promise for better outcomes by setting the basis of a precision medicine approach.
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Affiliation(s)
- Fiammetta Vanoli
- Neuroimmunology and Neuromuscular Disease Department, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
- Department of Human Neurosciences, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185, Rome, Italy
| | - Renato Mantegazza
- Neuroimmunology and Neuromuscular Disease Department, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy.
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15
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McCombe JA, Pittock SJ. Anti-complement Agents for Autoimmune Neurological Disease. Neurotherapeutics 2022; 19:711-728. [PMID: 35553024 PMCID: PMC9294087 DOI: 10.1007/s13311-022-01223-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/14/2022] [Indexed: 01/06/2023] Open
Abstract
In recent years, there has been increasing recognition of the diversity of autoimmune neurological diseases affecting all levels of the nervous system. A growing understanding of disease pathogenesis has enabled us to better target specific elements of the immune system responsible for the cell dysfunction and cell destruction seen in these diseases. This is no better demonstrated than in the development of complement directed therapies for the treatment of complement mediated autoimmune neurological conditions. Herein, we describe the basic elements of the complement cascade, provide an overview of select autoimmune neurological diseases whose pathogenesis is mediated by complement, the effector system of autoantigen bound autoantibodies, and discuss the complement directed therapies trialed in the treatment of these diseases. Several complement-directed therapies have demonstrated benefit in the treatment of autoimmune neurological diseases; we also review the trials resulting in the approval of these therapies for the treatment of AChR Ab-positive myasthenia gravis (MG) and neuromyelitis spectrum disorder. Finally, on the heels of the recent successes described, we discuss possibilities for the future, including additional targeted therapies with greater ease of administration, improved risk profiles, and other possible uses for therapeutics targeting elements of the complement cascade.
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Affiliation(s)
- Jennifer A McCombe
- Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA
- Division of Neurology, Department of Medicine, University of Alberta, Edmonton, AB, Canada
| | - Sean J Pittock
- Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA.
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16
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Alhaidar MK, Abumurad S, Soliven B, Rezania K. Current Treatment of Myasthenia Gravis. J Clin Med 2022; 11:jcm11061597. [PMID: 35329925 PMCID: PMC8950430 DOI: 10.3390/jcm11061597] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 03/09/2022] [Accepted: 03/10/2022] [Indexed: 02/04/2023] Open
Abstract
Myasthenia gravis (MG) is the most extensively studied antibody-mediated disease in humans. Substantial progress has been made in the treatment of MG in the last century, resulting in a change of its natural course from a disease with poor prognosis with a high mortality rate in the early 20th century to a treatable condition with a large proportion of patients attaining very good disease control. This review summarizes the current treatment options for MG, including non-immunosuppressive and immunosuppressive treatments, as well as thymectomy and targeted immunomodulatory drugs.
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17
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Song Z, Zhang J, Meng J, Jiang G, Yan Z, Yang Y, Chen Z, You W, Wang Z, Chen G. Different Monoclonal Antibodies in Myasthenia Gravis: A Bayesian Network Meta-Analysis. Front Pharmacol 2022; 12:790834. [PMID: 35115936 PMCID: PMC8804097 DOI: 10.3389/fphar.2021.790834] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Accepted: 12/10/2021] [Indexed: 11/13/2022] Open
Abstract
Background: Myasthenia gravis (MG) is a common autoimmune disease with acquired neuromuscular transmission disorders. Recently, monoclonal antibodies have been shown to successfully treat a variety of diseases. Methods: In this meta-analysis, an appropriate search strategy was used to search eligible randomized controlled trials (RCTs) on different monoclonal antibodies to treat patients with MG published up to September 2021 from the embase, PubMed, and Cochrane Library. We assessed the average difference or odds ratio between each drug and placebo and summarized them as the average and 95% confidence interval (CI), respectively. Results: In indicators of efficacy, patients receiving eculizumab (MD, −1.9; 95% CI, −3.2–0.76) had decreases in MG-ADL scores compared to placebo. In addition, only eculizumab (MD, −3.1; 95% CI, −4.7–1.5) and efgartigimod (MD, −1.4; 95% CI, −2.1–0.68) showed a significant difference from placebo in the amount of reduction in QMG scores, while neither of the other two monoclonal antibodies was statistically significant. With regard to the safety of monoclonal antibody therapy, there was no significant difference in the probability of AE in subjects treated with any of the four monoclonal antibodies compared to placebo. Conclusions: eculizumab was effective in reducing MG-ADL scores and QMG scores in myasthenia gravis. Meanwhile, eculizumab also caused fewer AE. As an emerging therapy, monoclonal antibodies are prospective in the treatment of MG. However, more researches are required to be invested in the future as the results obtained from small sample sizes are not reliable enough.
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Affiliation(s)
- Zhaoming Song
- Department of Neurosurgery and Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Jie Zhang
- Department of Neurosurgery and Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Jiahao Meng
- Department of Neurosurgery and Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Guannan Jiang
- Department of Neurosurgery and Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Zeya Yan
- Department of Neurosurgery and Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Yanbo Yang
- Department of Neurosurgery, China-Japan Friendship Hospital, Beijing, China
| | - Zhouqing Chen
- Department of Neurosurgery and Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Wanchun You
- Department of Neurosurgery and Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, Suzhou, China
- *Correspondence: Wanchun You, ; Zhong Wang,
| | - Zhong Wang
- Department of Neurosurgery and Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, Suzhou, China
- *Correspondence: Wanchun You, ; Zhong Wang,
| | - Gang Chen
- Department of Neurosurgery and Brain and Nerve Research Laboratory, The First Affiliated Hospital of Soochow University, Suzhou, China
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18
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Monteleone JPR, Gao X, Kleijn HJ, Bellanti F, Pelto R. Eculizumab Pharmacokinetics and Pharmacodynamics in Patients With Generalized Myasthenia Gravis. Front Neurol 2021; 12:696385. [PMID: 34795626 PMCID: PMC8594444 DOI: 10.3389/fneur.2021.696385] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Accepted: 08/20/2021] [Indexed: 11/17/2022] Open
Abstract
Objective: To investigate the pharmacokinetics, pharmacodynamics, and exposure-response of the approved 900/1,200 mg dosing regimen for the terminal complement component 5 (C5) inhibitor eculizumab in patients with generalized myasthenia gravis (gMG). Methods: The analysis used data from 62 patients aged ≥ 18 years with anti-acetylcholine receptor (AChR) antibody-positive refractory gMG who received eculizumab during the REGAIN study (ClinicalTrials.gov: NCT01997229). One- and two-compartment population-pharmacokinetic models were evaluated, and the impact of covariates on pharmacokinetic parameters was assessed. Relationships between eculizumab exposure and free C5 concentration, in vitro hemolytic activity, clinical response, and tolerability were characterized. Results: Steady-state serum eculizumab concentrations were achieved by Week 4 and were sustained throughout the 26-week treatment period. The eculizumab pharmacokinetic data were well-described by a two-compartment model with first-order elimination, including effects of body weight on pharmacokinetic parameters and plasma-exchange events on clearance. Complete inhibition of terminal complement was achieved in nearly all patients at the time of trough and peak eculizumab concentrations at all post-dose timepoints assessed (free C5 < 0.5 μg/ml in 92% of patients; in vitro hemolysis < 20% in 87% of patients). Serum eculizumab concentrations of ≥116 μg/ml achieved free C5 concentrations of < 0.5 μg/ml. Clinical efficacy and tolerability were consistent across the eculizumab exposure range. Conclusions: Rigorous, quantitative, model-based exposure-response analysis of serum eculizumab concentration and response data demonstrated that the approved eculizumab dosing (900/1,200 mg) for adults with anti-AChR antibody-positive refractory gMG rapidly achieved complete inhibition of terminal complement activation and provided sustained clinical efficacy across the eculizumab exposure range.
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Affiliation(s)
- Jonathan P. R. Monteleone
- Department of Pharmacometrics, PK/PD M&S, Clinical Development and Translational Sciences, Alexion Pharmaceuticals Inc., Boston, MA, United States
| | - Xiang Gao
- Department of Pharmacometrics, PK/PD M&S, Clinical Development and Translational Sciences, Alexion Pharmaceuticals Inc., Boston, MA, United States
| | | | | | - Ryan Pelto
- Department of Pharmacometrics, PK/PD M&S, Clinical Development and Translational Sciences, Alexion Pharmaceuticals Inc., Boston, MA, United States
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19
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Xiao H, Wu K, Liang X, Li R, Lai KP. Clinical Efficacy and Safety of Eculizumab for Treating Myasthenia Gravis. Front Immunol 2021; 12:715036. [PMID: 34456922 PMCID: PMC8384962 DOI: 10.3389/fimmu.2021.715036] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 07/26/2021] [Indexed: 12/18/2022] Open
Abstract
Myasthenia gravis (MG) is an autoimmune disease primarily mediated by acetylcholine receptor antibodies (AChR-Ab), cellular immune dependence, and complement system involvement. Since the AChR on the postsynaptic membrane is destroyed by an immune attack, sufficient endplate potential cannot be generated, resulting in the development of a synaptic transmission disorder at the neuromuscular junction and in muscle weakness. The role of the complement system in MG has been demonstrated in animal models and clinical tests, and it has been determined that complement inhibition in patients with MG can prevent disease induction and reverse its progression. Eculizumab is a humanized monoclonal antibody that inhibits the cleavage of complement protein C5 and prevents autoimmune damage; additionally, it has received subsequent approval by the Federal Drug Administration of the United States for MG treatment. However, various concerns regarding the use of eculizumab persist. In this review, we have discussed the treatment time, cost effectiveness, long-term efficacy, and tolerability of eculizumab for MG treatment. We have also summarized historical information and have presented perspectives on this new therapeutic modality.
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Affiliation(s)
- Hai Xiao
- Department of Neurology, Guigang City People’s Hospital, The Eighth Affiliated Hospital of Guangxi Medical University, Guigang, China
| | - Ka Wu
- Department of Pharmacy, The Second People’s Hospital of Nanning City, The Third Affiliated Hospital of Guangxi Medical University, Nanning, China
| | - Xiaoliu Liang
- College of Pharmacy, Guangxi Medical University, Nanning, China
| | - Rong Li
- Laboratory of Environmental Pollution and Integrative Omics, Guilin Medical University, Guilin, China
| | - Keng Po Lai
- Laboratory of Environmental Pollution and Integrative Omics, Guilin Medical University, Guilin, China
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20
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Frykman H, Kumar P, Oger J. Immunopathology of Autoimmune Myasthenia Gravis: Implications for Improved Testing Algorithms and Treatment Strategies. Front Neurol 2020; 11:596621. [PMID: 33362698 PMCID: PMC7755715 DOI: 10.3389/fneur.2020.596621] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Accepted: 11/19/2020] [Indexed: 12/13/2022] Open
Abstract
Myasthenia gravis (MG) is a heterogeneous condition, characterized by autoantibodies (Abs) that target functionally important structures within neuromuscular junctions (NMJ), thus affecting nerve-to-muscle transmission. MG patients are more often now subgrouped based on the profile of serum autoantibodies, which segregate with clinical presentation, immunopathology, and their response to therapies. The serological testing plays an essential role in confirming MG diagnosis and guiding disease management, although a small percentage of MG patients remain negative for antibodies. With the advancements in new highly effective pathophysiologically-specific immunotherapeutic options, it has become increasingly important to identify the specific Abs responsible for the pathogenicity in individual MG patients. There are several new assays and protocols being developed for the improved detection of Abs in MG patients. This review focuses on the divergent immunopathological mechanisms in MG, and discusses their relevance to improved diagnostic and treatment. We propose a comprehensive "reflex testing," algorithm for the presence of MG autoantibodies, and foresee that in the near future, the convenience and specificity of novel assays will permit the clinicians to consider them into routine systematic testing, thus stimulating laboratories to make these tests available. Moreover, adopting treatment driven testing algorithms will be crucial to identify subgroups of patients potentially benefiting from novel immunotherapies for MG.
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Affiliation(s)
- Hans Frykman
- Department of Medicine, University of British Columbia, Vancouver, BC, Canada.,BC Neuroimmunology Lab, University of British Columbia, Vancouver, BC, Canada
| | - Pankaj Kumar
- BC Neuroimmunology Lab, University of British Columbia, Vancouver, BC, Canada
| | - Joel Oger
- Department of Medicine, University of British Columbia, Vancouver, BC, Canada.,BC Neuroimmunology Lab, University of British Columbia, Vancouver, BC, Canada
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