Safety and Efficacy Study of Ravulizumab in Adults With Generalized Myasthenia Gravis

Inclusion Criteria:

1. Diagnosed with Myasthenia Gravis at least 6 months (180 days) prior to the date ofthe Screening Visit as confirmed by specific criteria.

2. Myasthenia Gravis Foundation of America Clinical Classification Class II to IV atscreening.

3. MG-ADL profile must be ≥ 6 at screening and randomization (Day 1).

4. Vaccinated against meningococcal infections within 3 years prior to, or at the timeof, initiating study drug to reduce the risk of meningococcal infection (Nmeningitidis).

Exclusion Criteria:

Medical Conditions

1. Any active or untreated thymoma. History of thymic carcinoma or thymic malignancyunless deemed cured by adequate treatment with no evidence of recurrence for ≥ 5years before screening.

2. History of thymectomy within the 12 months prior to screening.

3. History of N meningitidis infection.

4. Use of the following within the time period specified below:

• IV immunoglobulin within 4 weeks of randomization

• Use of plasma exchange within 4 weeks of randomization

• Use of rituximab within 6 months of screening

5. Participants who have received previous treatment with complement inhibitors (forexample, eculizumab).