Inclusion Criteria:

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

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

   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 time
   of, initiating study drug to reduce the risk of meningococcal infection (N
   meningitidis).

Exclusion Criteria:

Medical Conditions

   1. Any active or untreated thymoma. History of thymic carcinoma or thymic malignancy
   unless deemed cured by adequate treatment with no evidence of recurrence for ≥ 5 years
   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 (for
   example, eculizumab).