Extension Study of ECU-MG-301 to Evaluate Safety and Efficacy of Eculizumab in Refractory Generalized Myasthenia Gravis

A Phase III, Open-label Extension Trial of ECU-MG-301 to Evaluate the Safety and Efficacy of Eculizumab in Subjects With Refractory Generalized Myasthenia Gravis (gMG)

To evaluate the safety and efficacy of eculizumab in the treatment of refractory generalized myasthenia gravis (gMG) as an extension study for the participants who previously completed Study ECU-MG-301(NCT01997229).

ECU-MG-302 was an extension study designed to provide the participants who completed Study ECU-MG-301 an opportunity to receive eculizumab and collect clinical data to provide long-term safety and efficacy information on eculizumab in participants with refractory gMG.

After receiving blinded study treatment (eculizumab or placebo) in Study ECU-MG-301 for 26 weeks, participants were eligible to enroll in the ECU-MG-302 extension study. Participants were to enter Study ECU-MG-302 within 2 weeks after completing their Week 26 visit in Study ECU-MG-301.

Study ECU-MG-302 consisted of a 4-week Blind Induction Phase to preserve the blinded nature of Study ECU-MG-301, an Open-Label Maintenance Phase (up to 4 years), and a Safety Follow-up visit 8 weeks after the last dose for participants who withdrew from the study or discontinued eculizumab treatment at any time and for any reason after receiving any amount of eculizumab.

Inclusion Criteria:

1. Participant has completed Study ECU-MG-301.
2. Participant has given written informed consent.
3. Participant was willing and able to comply with the protocol requirements for the duration of the study.
4. Female participant of childbearing potential must have had a negative pregnancy test (serum human chorionic gonadotropin). All participants were required to practice an effective, reliable, and medically approved contraceptive regimen during the study and for up to 5 months following discontinuation of treatment.

Exclusion Criteria:

1. Participants who withdrew from Study ECU-MG-301 as a result of an adverse event related to study drug.
2. Female participants who were pregnant, breastfeeding, or intended to conceive during the course of the study.
3. Unresolved meningococcal infection
4. Hypersensitivity to murine proteins or to one of the excipients of eculizumab
5. Any medical condition or circumstances that, in the opinion of the investigator, might have interfered with the participant's participation in the study, posed any added risk for the participant, or confounded the assessment of the participants.