Inclusion Criteria:
1. Age ≥ 18 years, no gender restrictions;
2. Patients with positive CSF anti-Vimentin antibodies（VIMA）, clinically consistent with the clinical features of VIMA-related diseases reported in JAMA Neurology 2024; 3. EDSS ≥ 3.5 points or evidence of disease activity as defined by the protocol within 1 year prior to screening.
Evidence of disease activity as defined by the protocol: One of the following manifestations within 6 months of the screening period: 1. Enlargement of lesions on brain or spinal cord MRI T2 sequence; 2. △EDSS \> 0; 3. At least two FS scores increase by 1 point or at least 1 FS increases by 2 points (excluding rectal/bladder and brain); 4. Symptoms lasting for more than 24 hours without fever and more than 30 days since the last episode. 4. Sign informed consent.
Exclusion Criteria:
1. Allergy to the study drug;
2. Known active infections during the screening period (excluding nail bed fungal infections or dental caries);
3. Underwent any surgical procedure within 4 weeks prior to screening, has evidence of other demyelinating diseases or progressive multifocal leukoencephalopathy (PML);
4. Positive serology for HIV or syphilis treponema or RPR during the screening period (if syphilis antibodies are negative, further serological testing for syphilis is not required);
5. Chronic hepatitis B virus or hepatitis C virus infection that meets the following criteria: • HBsAg positive; • If HBsAg negative, HbcAb positive, further HBV DNA testing (result ≥1000 IU/mL); • If HCV antibody testing is positive, further HCV RNA testing (result above the upper limit of normal range at the research site);
6. Evidence of active tuberculosis (excluding patients receiving medication for latent TB infection);
7. Received any live vaccine or attenuated live vaccine within 6 weeks prior to the medication;
8. History of malignant tumors within 5 years prior to screening, including solid tumors, hematological malignancies, and carcinoma in situ (excluding fully resected and cured basal cell carcinoma, squamous cell carcinoma, and cervical carcinoma in situ);
9. Pregnant or breastfeeding women; for women of childbearing potential, a positive serum pregnancy test at screening, or unwilling to use reliable contraception (physical barriers \[patient or partner\] and spermicide, contraceptive pills, patches, injections, intrauterine devices or systems), and continuing for at least 4 months after the last administration of the study drug. Men of childbearing potential unwilling to use effective contraceptive measures during the period from signing the informed consent to 6 months after the last medication;
10. Any other diseases determined by the investigator that would make the subject unsuitable for participation in this study;
11. Presence of the following clinically significant diseases:
1. Echocardiography during the screening period shows a left ventricular ejection fraction (EF) below 50% or below the lower limit of normal values at the research center; history of chronic congestive heart failure, functional class NYHA III-IV;
2. Any of the following events occurred within 3 months prior to signing the informed consent: myocardial infarction, acute coronary syndrome, viral myocarditis, pulmonary embolism, stroke; coronary revascularization surgery within 6 months;
3. Electrocardiogram during the screening period indicates QTc interval \>480ms (according to Fridericia's correction formula, where QTc=QT/RR\^0.33), or history of severe QTc interval prolongation;
12. Laboratory test values during the screening period show the following abnormalities:
1. Aspartate aminotransferase (AST) \> 3× upper limit of normal (ULN), alanine aminotransferase (ALT) \> 3× ULN, total bilirubin \> 1.5× ULN (unless due to Gilbert's syndrome);
2. Platelet count \<50,000/μL (or \<50 × 10\^9/L), hemoglobin \<9 g/dL (or \<90 g/L), white blood cells \<2.0 × 10\^3/μL, absolute neutrophil count \<1.0 × 10\^3/μL;
3. Creatinine clearance (CLcr) \<60 mL/min (calculated using the Cockcroft-Gault formula: \[140 - age (years)\] × \[weight (kg)\] × (0.85, if female) / \[72 × serum creatinine (mg/dL)\]) or undergoing dialysis during screening.
