A Phase 3, Randomized, Double-Blind, Placebo-Controlled, Multicenter
Study to Evaluate the Safety and Efficacy of Ravulizumab in Complement-
Inhibitor-Naïve Adult Patients With Generalized Myasthenia Gravis

1. Male and female patients must be aged >= 18 years of age at the time of
signing the informed consent
2. Diagnosed with MG at least 6 months (180 days) prior to the date of the
Screening Visit
3. Confirmation of eligibility by:
a. Positive serologic test for anti-AChR Abs as confirmed at screening, and
b. One of the following (either historical or during screening):
• Abnormal neuromuscular transmission test demonstrated by single-fiber
electromyography or repetitive nerve stimulation
• Positive anticholinesterase test (eg, edrophonium chloride test)
• Demonstrated improvement in MG signs on oral cholinesterase inhibitors, as
assessed by the treating physician
4. Myasthenia Gravis Foundation of America Clinical Classification Class II to
IV at screening
5. MG-ADL profile must be >= 6 at screening and randomization (Day 1)
6. Patients receiving treatment with any of the following must have been
receiving treatment and on a stable dose for the time periods specified below
prior to the date of the Screening Visit:
• Azathioprine (AZA): Must have been on AZA for >= 6 months (180 days) and have
been on a stable dose for >= 2 months (60 days)
• Immunosuppressive therapies (ie, mycophenolate mofetil [MMF], methotrexate
[MTX], cyclosporine [CYC], tacrolimus [TAC], or cyclophosphamide [CY]), must
have been on the IST for >= 3 months (90 days) and have been on a stable dose
for >= 1 month (30 days)
• Oral corticosteroids, must have been on a stable dose for >= 4 weeks (28 days)
• A cholinesterase inhibitor, at the time of the Screening Visit, must have
been on a stable dose for >= 2 weeks (14 days)
7. To reduce the risk of meningococcal infection (N meningitidis), all patients
must be vaccinated against meningococcal infections within the 3 years prior
to, or at the time of, initiating study drug. Patients who initiate study drug
treatment less than 2 weeks after receiving a meningococcal vaccine must
receive treatment with appropriate prophylactic antibiotics until 2 weeks after
vaccination
8. Body weight >= 40 kg at the time of screening
9. Patients of childbearing potential and patients with partners of
childbearing potential must follow protocol-specified contraception guidance
for avoiding pregnancy while on treatment and for 8 months after last dose of
study drug
10. Capable of giving signed informed consent which includes compliance with
the requirements and restrictions listed in the informed consent form (ICF) and
in the protocol

1. Any active or untreated thymoma or history of thymic carcinoma or thymic
malignancy
Note: Treated patients with history of thymoma other than thymic carcinoma
corresponding to clinical stage 1 and 2 with no evidence of recurrence as
defined by a recent negative imaging study (CT scan with IV contrast or MRI
scan within 6 months of randomization) are eligible for enrollment.
2. History of thymectomy, thymomectomy, or any thymic surgery within the 12
months prior to screening
3. History of hypersensitivity to any ingredient contained in the study drug,
including hypersensitivity to murine proteins
4. History of N meningitidis infection
5. Human immunodeficiency virus (HIV) infection (evidenced by HIV-1 or HIV-2
antibody titer)
6. Known medical or psychological condition(s) or risk factor that, in the
opinion of the Investigator, might interfere with the patient*s full
participation in the study, pose any additional risk for the patient, or
confound the assessment of the patient or outcome of the study
7. History of hospitalization for >= 24 hours, for any reason, within the 4
weeks (28 days) prior to screening
8. Clinical features that, in the opinion of the Investigator, consistent with
MG crisis/exacerbation or Clinical Deterioration, at the time of the Screening
Visit or at any time prior to randomization
9. Female patients who plan to become pregnant or are currently pregnant or
breastfeeding
10. Female patients who have a positive pregnancy test result at screening or
on Day 1
11. Use of the following within the time period specified below:
• IVIg within the 4 weeks (28 days) prior to randomization (Day 1)
• Use of PE within the 4 weeks (28 days) prior to randomization (Day 1)
• Use of rituximab within the 6 months (180 days) prior to screening
12. Patients who have received previous treatment with complement-inhibitors
(eg, eculizumab)
13. Participation in another interventional treatment study or use of any
experimental therapy within 30 days before initiation of study drug on Day 1 in
this study or within 5 half-lives of the study drug, whichever is greater
14. History of unexplained infections
15. Active systemic bacterial, viral, or fungal infection within 14 days prior
to study drug administration on Day 1
16. Presence of fever >= 38°C (100.4°F) within 7 days prior to study drug
administration on Day 1