Department of Biomedicine, Neuroscience and advanced Diagnostic, University of Palermo, Palermo, Sicily, Italy
Department of Neuroscience Imaging and Clinical Sciences, Gabriele d'Annunzio University of Chieti and Pescara, Chieti, Abruzzo, Italy.
J Neurol Neurosurg Psychiatry. 2020 Apr;91(4):392-395. doi: 10.1136/jnnp-2019-322606. Epub 2020 Feb 25.
Myasthenia gravis (MG) is a chronic autoimmune disorder of the neuromuscular junction characterised by an autoantibody against acetylcholine receptor (AChR-Ab), autoantibody against muscle-specific kinase (MuSK-Ab), lipoprotein-related protein 4 or agrin in the postsynaptic membrane at the neuromuscular junction. Many patients are resistant to conventional treatment and effective therapies are needed. Rituximab (RTX) is a monoclonal antibody directed against CD20 antigen on B cells which has been successfully employed in anti-MuSK-Ab+MG, but the efficacy in anti-AChR-Ab+MG is still debated. The purpose of this systematic review was to describe the best evidence for RTX in the acetylcholine receptor subtype. The authors undertook a literature search during the period of 1999-2019 according to the Preferred Reporting Items for Systematic Reviews and Meta-Analys methodology, employing (myasthenia)+(gravis)+(RTX) as search terms. The analysis was confined to studies that include at least five patients with confirmed anti-AChR-Ab+MG. Thirteen studies have been selected, showing a good safety. The data obtained were heterogeneous in terms of posology, administration scheme and patients' evaluation, ranging from a minimum of two to a maximum of three cycles. RTX led to a sustained clinical improvement with prolonged time to relapse, in parallel to a reduction or discontinuation of other immunosuppressive therapies. Treatment with RTX appears to work in some but not all patients with anti-AChR-Ab+MG, but randomised controlled trials are needed. Future studies should take into account the subtype of MG and employ reliable measures of outcome and severity focusing on how to identify patients who may benefit from the treatment. Trial registration number: NCT02110706.
重症肌无力（MG）是一种慢性自身免疫性疾病，以神经肌肉接头处乙酰胆碱受体（AChR-Ab）、肌肉特异性激酶（MuSK-Ab）、脂蛋白相关蛋白 4 或神经肌肉接头后膜上的神经节苷脂自身抗体为特征。许多患者对常规治疗有抗药性，需要有效的治疗方法。利妥昔单抗（RTX）是一种针对 B 细胞 CD20 抗原的单克隆抗体，已成功应用于抗 MuSK-Ab+MG，但在抗 AChR-Ab+MG 中的疗效仍存在争议。本系统评价的目的是描述 RTX 在乙酰胆碱受体亚型中的最佳证据。作者根据系统评价和荟萃分析的首选报告项目，按照 1999 年至 2019 年的文献检索，采用（重症肌无力）+（肌无力）+（RTX）作为检索词进行文献检索。分析仅限于至少包含 5 例确诊为抗 AChR-Ab+MG 的患者的研究。共选择了 13 项研究，显示出良好的安全性。在剂量、给药方案和患者评估方面，所获得的数据存在异质性，从最少 2 个周期到最多 3 个周期不等。RTX 导致临床持续改善，复发时间延长，同时减少或停用其他免疫抑制治疗。RTX 治疗似乎对一些但不是所有抗 AChR-Ab+MG 患者有效，但需要进行随机对照试验。未来的研究应考虑 MG 的亚型，并采用可靠的结局和严重程度测量方法，重点关注如何识别可能从治疗中受益的患者。试验注册号：NCT02110706。
