Acute ischemic stroke (AIS) is a common type of stroke in the elderly. Timely blood flow recovery can effectively improve the long-term prognosis of patients. According to five large-scale multicenter randomized controlled trials (MR clean, swift-prime, revascat, escape and extend-ia) in recent years, the effect of endovascular therapy (EVT) for acute anterior circulation occlusion of great vessels is significantly better than that of drug therapy alone. Therefore, for patients who meet the "Chinese guidelines for the diagnosis and treatment of acute ischemic stroke" (2018 Edition), the effect of EVT is better than that of drug therapy alone, Intravenous thrombolysis within 4.5 hours and endovascular mechanical thrombectomy within 6 hours can effectively relieve the clinical symptoms and reduce the mortality of AIS. However, due to the narrow application time window of intravenous thrombolysis and mechanical thrombectomy, although the thrombectomy time window of some eligible patients was relaxed to 24 hours after dawn and defuse3 and other related studies, the reperfusion injury after the blocked cerebral artery recanalization has brought huge obstacles to clinical application. Therefore, how to improve the prognosis of patients with endovascular therapy has become a hot research direction.

Fingomod is a kind of sphingosine analogues acting on sphingosine-1-phosphate (sipr). After phosphorylation in the body, fingomod combines with lymphocyte SIP receptor, changes lymphocyte migration route, prevents it from entering the area outside the lymphoid tissue, so as to avoid its infiltration into the central nervous system and achieve immunosuppression. Currently, it is the first-line disease modifying oral drug for multiple sclerosis. Fingolmod shows neuroprotective effects on many central nervous system diseases including cerebral ischemia. Fingomod not only reduced the number of lymphocytes invading the brain, but also decreased the number of lymphocytes in the microcirculation system

Inclusion Criteria:

• The patient was over 18 years old;
• The NIHSS score was < 30 and NIHSS > 5;
• CTA / MRA / DSA confirmed occlusion of M1 segment of internal carotid artery or middle cerebral artery, and aspect score ≥ 6;
• CTP or MRI showed mismatch (ischemic core volume < 70ml, CTP mismatch > 1.2
• Normal to random time within 24 hours
• Written informed consent signed by patients or their families

Exclusion Criteria:

• Standard contraindications to alteplase or mechanical thrombectomy
• Cerebral hemorrhage confirmed by imaging
• Cardiovascular diseases (such as bradycardia, etc.)
• Systolic blood pressure > 185mmhg or diastolic blood pressure > 110mmhg, and oral antihypertensive drugs can not be controlled
• Pregnant or lactating women