This study is a phase I clinical study of the safety, tolerability, and pharmacokinetics of BAT4406F injection in patients with neuromyelitis optica spectrum disorders.

This is a Phase 1, open-label, dose-escalation study in NMOSD patients in which subjects will receive BAT4406F injection via intravenous infusion. A 3 + 3 design will be utilized to define a maximum tolerated dose (MTD). The overall objective is to assess the safety, tolerability, and pharmacokinetics of BAT4406F injection in NMOSD patients.

Inclusion Criteria:

• Compliance with the NMOSD diagnostic criteria developed by the 2015 International NMO Diagnostic Team (IPND);
• 18-65 years old , male or female;
• At least 2 relapses occurred within 2 years before screening, or at least 1 relapse within 1 year before screening;
• Discontinue the immunosuppressive agents such as azathioprine within 28 days before the baseline;
• EDSS score ≤ 6;
• Men and women with fertility must agree to use effective methods of contraception during treatment and within 12 months of treatment completion;
• Agree to participate in the trial and sign the informed consent in writing.

Exclusion Criteria:

• Any monoclonal antibody treatment was used within 6 months prior to dosing;
• Having been treated with anti-CD20 monoclonal antibody;
• Live vaccine received within 4 weeks before screening;
• Having participated in another clinical study within 1 month or 5 half-lives of the drug prior to the baseline (whichever is longer);
• A history of allergies to monoclonal antibodies; severe allergic reaction to certain foods or drugs;
• Abnormal liver function, kidney function and bone marrow reserve;
• HIV-positive history or HIV-positive at screening; hepatitis B and/or hepatitis C history or hepatitis B surface antigen-positive at screening; or hepatitis C virus (HCV) antibody positive; treponema pallidum antibody positive when enrolled;
• History of infections that investigators have identified as unsuitable for testing;
• Patients with a clear history of heart disease ;
• Have a history of mental disorders;
• Pregnant or lactating women, and female subjects who have a positive pregnancy test at screening;
• None of the investigators or their relatives participating in the study could be enrolled.