Focus on myasthenia gravis! Experts: Innovative therapies promise breakthrough change

Text/Yangcheng Evening News all-media reporter Yu Yanhong

Myasthenia gravis is a rare chronic autoimmune neuromuscular disease caused by dysfunction of nerve-muscle junction transmission. As a rare disease in neuroimmune diseases, myasthenia gravis has attracted the attention of clinical experts due to its long course, difficult treatment, and multiple recurrences.

Recently, the world's first FcRn antagonist efgartigimod was approved by the U.S. Food and Drug Administration (FDA) for the treatment of adults with acetylcholine receptor (AChR) antibody-positive generalized myasthenia gravis (gMG).

This means that efgartigimod has become a new breakthrough in innovative drugs for myasthenia gravis for many years, providing a new treatment for overcoming generalized myasthenia gravis.

Photo/Visual China (picture and text independent)

Half of patients with myasthenia gravis develop the disease for the first time at the golden age of life

As early as 2018, myasthenia gravis has been included in the "First Rare Disease Catalogue" jointly issued by the five ministries and commissions of the state. In China, the incidence of myasthenia gravis is about 0.68/100,000 person-years, the incidence of women is higher than that of men, and mainly young adults, many patients have their first onset in the golden age, one in four patients have symptoms before the age of 19, and more than half of patients have symptoms before the age of 30.

From the perspective of pathogenesis characteristics, the main symptoms of patients with myasthenia gravis are eyelid drooping, diplopia, arm, leg and foot weakness, dysphagia, slurred speech, etc., especially generalized myasthenia gravis, which mainly affects swallowing, speaking, walking and even breathing function, resulting in obvious muscle weakness and even life-threatening.

These symptoms are difficult to attract patient attention and timely medical attention in the early stages, but if symptoms are not well controlled, they can seriously affect daily life and work, and damage the patient's mobility and quality of life.

"Currently, the most common treatment options for myasthenia gravis are cholinesterase inhibitors, glucocorticoids, immunosuppressants, intravenous immunoglobulins, plasmapheresis, anti-CD20 monoclonal antibodies, and thymosectomy. Although these classic regimens offer a number of treatment options, there are limitations in the treatment of myasthenia gravis. ”

Professor Yang Huan, chief physician of the Department of Neurology of Xiangya Hospital of Central South University, pointed out that "cholinesterase inhibitors are mostly used for symptomatic treatment, long-term treatment needs to be combined with other drugs, gastrointestinal and other side effects are common, so a large proportion of patients rely on high-dose hormones and immunosuppressants to maintain treatment; and glucocorticoids, some patients are difficult to maintain the efficacy, but long-term use of large doses can have significant multi-system side effects, and the adverse reactions of these drugs lead to poor patient compliance; the individual differences in immunosuppressant efficacy are large. Lack of clinical research to compare the efficacy and safety of different regimens, drug selection depends on the experience of doctors; and anti-CD20 monoclonal antibody, some patients by existing drugs, poor efficacy, or contraindications to drug use, intravenous immunoglobulins and plasmapheresis due to insufficient supply, expensive, resulting in poor accessibility, and there are risks of infection, kidney function damage and so on. ”

Innovative therapies promise to revolutionize the treatment of myasthenia gravis

Professor Lu Jiahong, chief physician of the Department of Neurology of Huashan Hospital affiliated to Fudan University, said that in China, the vast majority of myasthenia gravis patients are receiving drug treatment, but there are still some patients who cannot fully and effectively control the disease due to drug efficacy, tolerance or contraindications or other issues; in addition, 10%-20% of refractory patients and 15%-20% of patients may develop crisis, which has become an important challenge in clinical treatment.

Nowadays, with the improvement of disease awareness and the continuous iteration of drug therapy, FcRn antagonists, as a safe and effective new treatment method, are expected to improve the treatment outcomes and quality of life of patients, which has attracted the attention of experts and scholars at home and abroad.

In June this year, the international authoritative medical journal "Lancet Neurology" published a new FcRn antagonist efgartigimod for adults systemic myasthenia gravis key phase III ADAPT clinical study, the results show that its treatment of adult generalized myasthenia gravis has good efficacy and safety, can bring clinical significance to patients with systemic myasthenia gravis and improve quality of life indicators, which is of great significance to patients.

Professor Lu Jiahong concluded: "Myasthenia gravis is one of the most well-defined antigens and antibodies today, and the pathogenesis of immunology is relatively clear. FcRn antagonists are expected to be a new breakthrough in innovative drugs for myasthenia gravis in the past 30 years, and will provide clinicians with innovative solutions to overcome myasthenia gravis. At the same time, as a new therapeutic drug that targets antibodies to highly target IgG antibodies for antibody-mediated autoimmune diseases, in the future, we also expect it to become a precision drug that completely changes autoimmune diseases. (For more news, please pay attention to Yangcheng Pie pai.ycwb.com)

Source | Yangcheng Evening News Yangcheng Pie

Editor-in-charge | Cui Wencan