A Phase 3 Open-Label Study of Eculizumab in Pediatric Participants With Refractory Generalized Myasthenia Gravis (gMG)

Inclusion Criteria: * Male or female pediatric participants 6 to \<18 years of age at time of assent/consent. * Vaccinated against Neisseria meningitidis. * Documented vaccination against Haemophilus influenzae and Streptococcus pneumoniae infections prior to dosing as per local and country specific immunization guidelines for the appropriate age group. * Diagnosis of MG confirmed by positive serologic test for anti-acetylcholine receptor antibodies at Screening, and 1 of the following: (a) history of abnormal neuromuscular transmission test demonstrated by single-fiber electromyography or repetitive nerve stimulation; (b) history of positive anticholinesterase test (for example, edrophonium chloride or neostigmine test); or (c) participant demonstrated improvement in MG signs on oral acetylcholinesterase inhibitors, as assessed by the Investigator. * Presence of refractory gMG, defined as participants with gMG who have 1 or more of the following: (a) failed treatment ≥1 year with at least 1 immunosuppressive therapies (IST), defined as follows: (1) persistent weakness with impairment of activities of daily living; (2) myasthenia gravis (MG) exacerbation and/or crisis while on treatment; or (3) intolerance to ISTs due to side effect or comorbid condition(s). (b) Require maintenance plasma exchange (PE) or intravenous immunoglobulin (IVIg) to control symptoms; and/or (c) in the opinion of the Investigator, MG poses a significant functional burden despite current MG treatment.…