A Study of Nipocalimab Administered to Adults With Generalized Myasthenia Gravis

Inclusion Criteria:

• Diagnosis of myasthenia gravis (MG) with generalized muscle weakness meeting theclinical criteria for generalized myasthenia gravis (gMG) as defined by theMyasthenia Gravis Foundation of America (MGFA) Clinical Classification Class II a/b,III a/b, or IVa/b at screening

• Myasthenia Gravis - Activities of Daily Living (MG-ADL) score of greater than orequal to (>=) 6 at screening and baseline

• Has sufficient venous access to allow drug administration by infusion and bloodsampling as per the protocol

• A woman of childbearing potential must have a negative highly sensitive serum (beta-human chorionic gonadotropin [beta-hCG]) at screening and a negative urinepregnancy test at Day 1 prior to administration of study intervention

• A male participant must agree not to donate sperm for the purpose of reproductionduring the study and for a minimum 90 days after receiving the last administrationof study intervention

• For the SC Substudy (Cohort 1): Has reasonable abdominal skin area for SCadministration

• For the SC Substudy (Cohort 1): Participants must be willing to comply withmaintaining their stable dose of corticosteroids and/or immunosuppressants for theinitial 8 weeks of the SC substudy, that is, through the SC Week 8 visit

Exclusion Criteria:

• Has any confirmed or suspected clinical immunodeficiency syndrome not related totreatment of his/her gMG, or has a family history of congenital or hereditaryimmunodeficiency unless confirmed absent in the participant

• Has MGFA Class I disease or presence of MG crisis (MGFA Class V) at screening,history of MG crisis within 1 month of screening, or fixed weakness (and/or 'burntout' MG)

• Has had a thymectomy within 12 months prior to screening, or thymectomy is plannedduring the study

• Has known allergies, hypersensitivity, or intolerance to nipocalimab or itsexcipients

• Has experienced myocardial infarction, unstable ischemic heart disease, or strokewithin 12 weeks of screening

• For the SC Substudy (Cohort 1): Participants who have undergone a recent tapering oftheir concomitant MG medication in the OLE

• For the SC Substudy (Cohort 1): Participants actively deteriorating at the SC Dose 1visit for the SC substudy such that they meet the criteria for ClinicalDeterioration