Immunotherapies in autoimmune neuromuscular junction disorders: Acute and chronic management.

Myasthenia gravis (MG) is the most common disease of the neuromuscular junction. Conventional immunotherapy based on corticosteroids and immunosuppressants has been in use for several decades and has greatly contributed to the improvement of the disease prognosis. In recent years, several new agents, mostly monoclonal antibodies, have proved effective in randomized controlled trials and are in clinical use. Other biologics are currently under evaluation. Novel therapies, that offer the advantage of more selective effects on the immune system, are not devoid of potentially serious adverse effects. MG subgrouping based on associated autoantibodies is a prerequisite for personalized treatment. Patient-specific selection is especially relevant and includes MG-specific IgG subclasses and B-cell subsets responsible for antibody production. While ever-growing knowledge of the disease pathogenicity and advances in technology have made such therapeutic advances possible, lack of biomarkers of disease activity complicates treatment decisions. On the other hand, treatment of Lambert-Eaton myasthenic syndrome (LEMS) has scarcely changed in recent decades and biologics have been tried in very few patients to date. Its rarity and association with cancer have likely discouraged the exploration of new immunotherapies for LEMS despite disease-related disability.