Management of Myasthenic Crisis and Emerging Roles of Molecularly Targeted Therapies: A Narrative Review.
Seiya Takahashi, Ryuta Kinno
Abstract
Open AccessMyasthenia gravis (MG) is a chronic autoimmune disorder characterized by fluctuating skeletal muscle weakness. Myasthenic crisis (MCr), a severe and potentially life-threatening complication, presents with respiratory failure and requires intensive care and rapid immunomodulatory intervention. Conventional MCr treatments-such as plasma exchange (PLEX), intravenous immunoglobulin (IVIG), and intravenous methylprednisolone (IVMP)-remain standard treatments; however, they present significant limitations, including delayed onset of action, adverse effects, and inconsistent efficacy. Recent therapeutic advances have led to the development of molecularly targeted therapies based on MG pathophysiology, particularly neonatal Fc receptor (FcRn) inhibitors and complement inhibitors, which have shown efficacy in refractory or maintenance settings. This review explores the potential application of these agents in MCr. We review published case reports involving FcRn inhibitors (efgartigimod, efgartigimod-SC, rozanolixizumab) and complement inhibitors (eculizumab, ravulizumab, zilucoplan), highlighting their rapid onset of action and safety profiles in MCr. While efgartigimod and eculizumab are the most commonly reported agents in MCr, data remain limited to small case series. Emerging evidence suggests these agents may offer effective alternatives to conventional therapies, with favorable safety and potential for rapid symptom resolution. We also discuss strategic considerations for therapy selection, including antibody subtype, coexisting autoimmune conditions, genetic factors, and transition to long-term maintenance. Though the current evidence is promising, large-scale randomized studies are needed to establish definitive roles for these therapies in MCr management.