Effect of Interleukin-6 Receptor Inhibition in Patients With Ischemic Stroke Undergoing Endovascular Treatment

Age 18-80 years.

Acute ischemic stroke caused by occlusion of intracranial segment of theinternal carotid artery, middle cerebral artery M1, or M2 segment.

NIHSS ≥ 6.

Meeting the criteria of endovascular treatment: ① ASPECTS score ≥ 6, possibile to start endovascular treatment within 6 hoursfrom stroke onset. ② Stroke onset between 6-16 hours, meeting DEFUSE-3 criteria (infarct corevolume < 70ml, mismatch ratio ≥ 1.8, and mismatch volume > 15ml), or DAWNcriteria (NIHSS ≥ 10 and infarct core volume < 31ml; or NIHSS ≥ 20 and infarctvolume 31-51ml). ③ Stroke onset between 16-24 hours, meeting DAWN criteria (NIHSS ≥ 10 andinfarct core volume < 31ml; or NIHSS ≥ 20 and infarct volume 31-51ml). ④ When ASPECTS score is < 6, meeting RESCUE-Japan LIMIT criteria (ASPECTS score 3-5; stroke onset within 6 hours or between 6-24 hours but no acute strokesigns on FLAIR), or ANGEL-ASPECT criteria (stroke onset within 24 hours,ASPECTS 3-5; or onset within 24 hours, ASPECTS 0-2 and infarct core volume 70-100 mL; or onset between 6-24 hours, ASPECTS > 5 and infarct core volume 70-100 mL), or SELECT2 criteria (ASPECTS 3-5; or infarct core volume greaterthan 50ml).

Experimental drug administration had to be possible within 24 hours afterstroke onset.

Obtained Informed consent from the patient or their legal representative.

Hemorrhagic diseases visible on head CT: hemorrhagic stroke, epidural hematoma,subdural hematoma, intraventricular hemorrhage, subarachnoid hemorrhage, etc.

Pre-stroke mRS score > 1.

Known allergy to tocilizumab or excipients.

Known allergy to iodinated contrast agents.

Anticipated difficulty in completing endovascular treatment due to vasculartortuosity.

History of congenital or acquired bleeding disorders, coagulation factordeficiency diseases, thrombocytopenic diseases, etc.

Systolic blood pressure ≥ 180 mmHg or diastolic blood pressure ≥ 110 mmHgdespite blood pressure control.

Neutrophil < 2×10 9/L.

Platelet < 100×10 9/L.

Blood glucose < 2.8 mmol/L (50 mg/dl) or > 22.2 mmol/L (400 mg/dl).

Serum alanine aminotransferase (ALT) or aspartate aminotransferase (AST) levelsgreater than 1.5 times the upper limit of normal.

Known recent or current serum creatinine exceeding 1.5 times the upper limit ofnormal or estimated glomerular filtration rate (eGFR) < 60 mL/min.

Pregnant, lactating, or planning pregnancy within 90 days.

Severe mental disorders or inability to comply with informed consent andfollow-up requirements due to dementia.

Concurrent malignant tumors or severe systemic diseases with an expectedsurvival of less than 90 days.

Presence of autoimmune diseases or use of immunosuppressive drugs.

Systemic infectious diseases

Participation in another interventional clinical study within 30 days beforerandomization or currently participating in another interventional clinicalstudy.