A Study of Telitacicept for the Treatment of Generalized Myasthenia Gravis (UPSTREAM MG)

Key Inclusion Criteria: 1. Male or female patient aged ≥18 years at screening. 2. Patients have prior confirmed diagnosis of gMG with generalized muscle weakness (typical pattern of weakness meeting the clinical criteria for diagnosis of MG as defined by the Myasthenia Gravis Foundation of America (MGFA) clinical classification II-IV. 3. Patients have positive antibodies against AChR or MuSK at screening. 4. MG-ADL score ≥6 points at screening and baseline with ocular-related score \<50% of the total score. 5. QMG score ≥8 points, and ≥ 4 items score at least 2 points at screening and baseline. Key Exclusion Criteria: 1. Patients have been diagnosed with any other autoimmune disease which can potentially pose a safety or efficacy confounding risk. 2. Patients having acute or chronic infection. 3. Patients having thymoma within 5 years or received thymectomy ≤6 months prior to screening. Patients with thymoma diagnosed 3-5 years prior to screening may be eligible if thymoma was at a localized stage and definitively treated with complete surgical resection. 4. Patients having current or history of primary immunodeficiency. 5. Patients having history of malignancy within the last 5 years. 6. Patient having prior or continuing diagnosis of serious cardiovascular, liver, kidney, respiratory system, endocrine or hematologic disease.