RecruitingRegistry of Participants With Generalized Myasthenia Gravis Treated With Alexion C5 Inhibition Therapies (C5ITs)Long-term, multicenter, multinational, observational, registry of patients with gMG that is designed to collect data on clinical outcomes and safety in patients prescribed Alexion C5 inhibitor therapies (C5IT) such as eculizumab (Soliris®) and ravulizumab (Ultomiris®).