INdobufen Versus aSpirin in acUte Ischemic stRokE,INSURE

Inclusion Criteria: * Female or male aged≥18 years and\<80years. * Acute moderate/severe ischemic stroke, 4≤NIHSS（National Institute of Health stroke scale）≤18 at the time of randomization. * Patients can be randomized within 72 hours of symptoms onset. * Provision of informed consent prior to any study specific procedures. \* Symptom onset is defined by the "last seen normal" principle Exclusion Criteria: * Diagnosis of intracerebral hemorrhage such as cerebral hemorrhage, subarachnoid hemorrhage, etc. * Diagnosis of hemorrhage or other pathology, such as vascular malformation, tumor, abscess or other major non-ischemic brain disease (e.g., multiple sclerosis) on baseline head CT or MRI. * Moderate to severe ischemic stroke induced by angioplasty/vascular surgery. * Modified Rankin Scale Score\>2 at randomization (pre-morbid historical assessment). * History of aneurysm (including intracranial aneurysm or peripheral aneurysms). * Clear indication for anticoagulation (presumed cardiac source of embolus, e.g., atrial fibrillation, atrial myxoma, prosthetic cardiac valves known or suspected endocarditis). * History of Hemostatic disorder, systemic bleeding, thrombocytopenia or neutropenia. * History of previous symptomatic non-traumatic intracerebral bleed or cerebral artery amyloidosis. * Gastrointestinal (GI) bleed within the past 6 months before randomization. * Major surgery within the past 3 months before randomization. * Severe renal or hepatic insufficiency. (Severe hepatic insufficiency is defined as alanine aminotransferase (ALT) value\>3 times normal upper limit or Aspartate aminotransferase (AST)\>2 times normal upper limit; Severe renal insufficiency is defined as creatinine\>2 times normal upper limit). * Diagnosis or of acute coronary syndrome. * Other antithrombotic therapy are required during the study, including antiplatelet therapy(such as open-labeled aspirin, GPIIb/IIIa inhibitors, clopidogrel, ticagrelor, prasugrel, dipyridamole, ozagrel, cilostazol, etc.) and anticoagulant therapy(such as warfarin, thrombin and factor Xa inhibitors, bivalirudin, hirudin, argatroban, heparin and low molecular heparin, etc.). * Within randomized 24 hours prior to any venous or arterial thrombolysis, mechanical bolt, snake venom, defibrase, lumbrokinase, etc. * Heparin or oral anticoagulants were used within 10 days of randomization. * Have a history of drug or food allergy and are known to be allergic to the study drug ingredients * Planned or likely revascularization (any angioplasty or vascular surgery) within the next 3 months (if clinically indicated, vascular imaging should be performed prior to randomization whenever possible) * Anticipated requirement for long-term (\>7 days) non-steroidal antiinflammatory drugs (NSAIDs). * The blood pressure needs to be controlled within the range of 90mmHg/60mmHg to 220mmHg/120mmHg. * Suffering from serious cardiopulmonary disease, the researchers believe that it is not suitable for this study * Patients with life expectancy\<3 months or patients who are unable to complete the study for other reasons. * Women of childbearing age who are negative in pregnancy test but refuse to practice reliable contraception. Women who are pregnant or lactating. * Involving in other investigational drug or device tests within the past 30 days before randomization. * Inability of the patient to understand and/or comply with study procedures and/or follow-up due to mental illness, cognitive or emotional disorders