• To be enrolled, subjects must meet all of the following criteria:

‣ Subjects or their legal representatives voluntarily sign a written informed consent and are willing and able to comply with the procedures of the study;

⁃ Subjects aged 18-75 years old (both inclusive), male or female;

⁃ Subjects with confirmed refractory gMG of classes IIa - IVb by MGFA clinical classification (including classes IIa, IIb, IIIa, IIIb, IVa and IVb) at screening;

⁃ Subjects with the Myasthenia Gravis - Activities of Daily Living (MG-ADL) score of ≥6, the proportion of ocular symptoms of \<50% of the total score, and the Quantitative Myasthenia Gravis (QMG) score of ≥11;

⁃ Subjects with poor response and/or who do not respond to the conventional therapies, that means subjects who are still at risk of relapse or exacerbation after conventional therapies with hormones, immunosuppressants (e.g., azathioprine, mycophenolate mofetil, tacrolimus, cyclosporin A, cyclophosphamide, methotrexate, etc.), or biological agents (e.g., rituximab);

⁃ For patients who are taking corticosteroids, the dose of prednisone should not exceed 30 mg/day (or an equivalent dose of other corticosteroids), and the dose must be stable for at least 4 weeks before infusion;

⁃ The laboratory test results during the screening period meet the following criteria:

• Neutrophil count ≥ 1.0×10\^9/L; Hemoglobin ≥ 8.0 g/dL; Platelet count≥50×10\^9/L;

∙ Alanine aminotransferase ≤ 3× upper limit of normal (ULN); Aspartate aminotransferase ≤ 3×ULN; total bilirubin (TBIL) \< 2× ULN (for subjects with Gilbert's syndrome), direct bilirubin (DBIL)) ≤ 1.5×ULN

∙ Creatinine clearance (19.3 Appendix 3) ≥ 30 mL/min;

∙ Activated partial thromboplastin time (APTT) ≤ 1.5×ULN, prothrombin time (PT)≤ 1.5×ULN;

∙ Subject's left ventricular ejection fraction (LVEF) is ≥ 50% by echocardiography, with no evidence of pericardial effusion as determined;

⁃ Female subjects of child-bearing age must:

• At screening, a negative serum β human chorionic gonadotropin β-hCG pregnancy test result confirmed by the investigator;

∙ Who agree to avoid breastfeeding during the study period until at least 1 year after the infusion of GC012F Injection or until two consecutive flow cytometry tests show the absence of CAR-T cells (whichever occurs later).

⁃ Male subjects with sexual partners and female subjects of potential child-bearing age shall agree to take effective contraceptive measures (e.g., oral contraceptive pills, intrauterine device or condom) from the screening period until at least 2 years after the infusion of GC012F Injection or until two consecutive flow cytometry tests show the absence of CAR-T cells (whichever occurs later). Male subjects must agree to use condoms during sexual contact with pregnant women or females of child-bearing age within at least 2 years after the infusion of GC012F Injection, even if a successful vasectomy has been performed;

‣ Subjects for whom venous access available for blood collection can be established, and with no contraindications to leukocyte collection.