Efficacy and Safety of Tocilizumab in the Treatment of Generalized Myasthenia Gravis

This study is a randomized, double-blind, placebo-controlled study, to be conducted at 6 study sites. Approximately 64 subjects will be enrolled. Patients with MG who are positive for anti-AChR antibodies will be enrolled. Patients who do not have anti-AChR or anti-MuSK antibodies will not be enrolled. Patients with MGFA classification II, III, or IV disease, MG-ADL score ≥ 5, QMG score ≥ 11, and use of a corticosteroid and/or non-steroidal immunosuppressant will be included in the study.

All subjects who complete the randomized controlled period will have the option to enroll in a 1-year open-label period.

Inclusion criteria

• Diagnosis of MG with anti-AChRantibody.
• MGFA Clinical Classification Class II, III, or IV.
• MG-ADL score of 5 or greater at screening and at randomization with > 50% of this score attributed to non-ocular items.
• QMG score of 11 or greater.
• Subjects must be on:

• Cholinesterase inhibitor, with no dose increase within 4 weeks prior to randomization;
• Corticosteroids, with no dose increase within 4 weeks prior to randomization; or/and c. non-steroidal IST (including azathioprine, mycophenolate mofetil, tacrolimus, cyclosporine A), with continuous use for at least 6 months prior to randomization and no dose increase within 4 months prior to randomization.

Exclusion criteria

• Participants had clinically relevant active infections (such as sepsis, pneumonia, or abscess) or severe infections (resulting in hospitalization or requiring antibiotic treatment) in the 4 weeks before randomization;
• Those with a history of high-risk tuberculosis infection, acquired tuberculosis infection, and chronic hepatitis;
• Human immunodeficiency virus (HIV) infection;
• Thymomas that have received thymectomy or planned thymectomy during RCP within 6 months before randomization, or require chemotherapy and/or radiotherapy at any time;
• Received rituximab treatment in the past 6 months before randomization;
• Received tocilizumab or eculizumab treatment within 3 months before randomization;
• Received IVIG or plasma exchange within 4 weeks before randomization;
• Unresected thymoma.
• History of other tumor diseases.