Clinical Trial of GenSci136 in Patients With Myasthenia Gravis

Who can take part

• Male or female, aged 18 to 70 years (both inclusive)
• standard-of-care (SoC) treatment for MG before screening
• Men of reproductive age and women of childbearing potential must agree to take highly effective contraceptive methods from screening to 5 months after the last dose4. Participants who can understand the trial procedures, voluntarily participate in the trial (themselves or through their legally acceptable representative), For participants with gMG: 1. Participants diagnosed with gMG with generalized muscle weakness, corresponding to Myasthenia Gravis Foundation of America (MGFA) clinical classification Class II-IV
• Positive for anti-AChR antibodies or anti-MuSK antibodies. 3. MG-ADL score must be ≥ 6, and the ocular score must account for < 50% of the total score. 4. QMG score must be ≥ 8, with at least 4 individual items scored ≥ 2. For participants with oMG: 1. Participants with a diagnosis of MG supported by the following medical documentation: a. Positive anti-AChR or anti-MuSK autoantibodies; or b. Abnormal neuromuscular transmission confirmed by single-fiber electromyography (SFEMG)/repetitive nerve stimulation (RNS), together with at least one of the following pharmacological/clinical confirmations: 1) documented positive ice pack test (resolution of ptosis after application of an ice pack to the eyelid for 2 minutes, with an improvement of > 2 mm); 2) documented positive edrophonium chloride (Tensilon) test, or a positive test with another cholinesterase inhibitor currently used in clinical practice to confirm oMG, such as the neostigmine test; or 3) documented improvement in MG signs following treatment with oral AChE inhibitors, plasma exchange, IVIg, glucocorticoids, or other relevant therapies. 2. Participants diagnosed with oMG, corresponding to MGFA clinical classification Class I. 3. the MGII (PRO) ocular score must be ≥ 6, and at least 2 ocular items must have a score of ≥ 2. 4. No pupillary abnormalities, except those caused by previous localized disease or surgery

Who cannot take part

• History of MG crisis within 1 month before screening
• Known hypersensitivity to GenSci136 or any of the excipients contained in the GenSci136 formulation, or history of serious hypersensitivity reactions to any drug
• Participants with diseases or dysfunctions (excluding MG) known to interfere with the clinical trial,
• Presence of acute or chronic infections requiring treatment at screening
• Diagnosis of any other autoimmune disease at screening other than MG, e.g., rheumatoid arthritis, Sjögren's syndrome (patients with abnormal thyroid function at screening will be excluded; those with autoimmune thyroiditis under stable control for ≥ 6 months and with normal thyroid function at screening may be exempted). 7. Participants who have attempted suicide within the past year or are currently at risk of impulsive behavior or suicide. 8. Participants with current or prior thymoma or thymectomy (except those meeting the criteria specified below), or planned thymectomy during the trial period. 9. Receipt of any live or live attenuated vaccine within 1 month before screening, or planned receipt of any live or live attenuated vaccine (except inactivated vaccine) during the trial period. 10. Receipt of intravenous, subcutaneous, or intramuscular immunoglobulin or plasma exchange within 1 month before screening. 11. Treatment with any form of CAR-T cell therapy, T-cell engager (TCE) therapy, or biologics targeting CD19/CD20 within 1 year before screening. 12. Positive hepatitis B virus at screening [hepatitis B surface antigen (HBsAg) positive; or HBsAg negative with hepatitis B core antibody (HBcAb) positive and hepatitis B virus deoxyribonucleic acid (HBV-DNA) positive or > upper limit of normal (ULN)], positive hepatitis C virus antibody (HCV-Ab), positive human immunodeficiency virus antibody (HIV-Ab), or positive syphilis serology test. 13. 12-lead ECG abnormalities during the screening period or at baseline, e.g., heart rate-corrected QT interval QTcF absolute value > 470 ms (Fridericia's formula: QTcF = QT/RR0.33) that, upon assessment by the investigator, may interfere with this clinical trial. 14. During the screening or baseline period, participants with any of the following abnormal laboratory test results: a) Absolute neutrophil count (ANC) < 1.2 × 10³/μL ; b) Platelet count < 75,000/μL (i.e., < 75 × 10⁹/L); c) Hemoglobin < 8.0 g/dL; d) IgG < 600 mg/dL; e) Creatinine > 1.5 × ULN or estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m2; f) Glycated hemoglobin (HbA1c) > 8.0%, except for participants whose blood glucose control is considered adequate by the investigator; g) Alanine aminotransferase (ALT) or aspartate aminotransferase (AST) > 2 × upper limit of normal (ULN), or total bilirubin (TBIL) > 1.5 × ULN; h) Other abnormal laboratory test results deemed by the investigator to make the participant unsuitable for participation in the study. 15. Participants judged by the investigator to be ineligible for other reasons
• Participants with a known history of malignant tumors (including but not limited to lung cancer, colorectal cancer, liver cancer, gastric cancer, esophageal cancer, prostate cancer, thyroid cancer, bladder cancer, pancreatic cancer, kidney cancer, breast cancer, cervical cancer, corpus uteri cancer, ovarian cancer and malignant melanoma) are excluded unless they have been free of recurrence for ≥ 3 years; basal cell carcinoma, non-metastatic squamous cell carcinoma of the skin, cervical carcinoma in situ, breast carcinoma in situ, and incidental prostate cancer T1a/T1b are not excluded under this criterion (for thymoma-related requirements, see Exclusion Criterion 8)