[Immunosuppressive / immunomodulating therapies in myasthenia gravis-at present and in the near future].

Myasthenia gravis (MG) is an autoimmune disorder of neuromuscular transmission that is primarily caused autoantibodies specific to the neuromuscular junction and is characterized by fatigability and weakness of the striated muscles. Immunosuppression is the mainstay of treatment for MG, and patients with MG are currently treated with immunomodulating or immunosuppressive agents. This review summarizes the current situation and perspective of medical therapy for MG, focusing on mechanisms of action and clinical application of corticosteroids and different classes of immunomodulating or immunosuppressive drugs used for MG. Immunosuppressive treatment is indicated for patients with disabling weakness, not sufficiently managed with cholinesterase inhibitors. Prednisolone (PSL) is used in the great majority of patients. Tacrolimus and cyclosporine are the first-line immunosuppressants, whereas azathioprine is a conventional but less frequently used medication in Japan. The incidence of late- and elderly-onset MG is reported to be increasing. The risk of complications in corticosteroid treatment appears to depend on drug dosage, treatment duration, and patients' characteristics, and the serious side effects should be increased in late- and elderly- onset MG. Although nonspecific, current immunosuppressive treatment is highly effective in most MG patients, the need for prolonged administration and unwanted effects are still relevant limitations to its use.