EFfects of Y-6 SUblingual Tablets foR PaTients With AcUte Ischemic StRokE (FUTURE)

Inclusion Criteria: * 35 years old ≤ Age ≤ 80 years old; * Patients with acute ischemic stroke diagnosed within 24 hours of onset (time from onset to start of endovascular treatment); * Patients with first stroke or mRS score 0-1 prior to this onset ; * Patients with acute intracranial large vessel occlusion (LVO) confirmed by imaging examination, including occlusion of intracranial segments of internal carotid arteries, T-shaped bifurcation, MCA M1 and/or M2 segments and ACA A1 and/or A2 segments; * ASPECTS score ≥ 6 when screening; * 6\<NIHSS score ≤ 25 after this onset; * Patients who had the indications for mechanical thrombectomy and were scheduled for endovascular treatment; * Patients or his/her legal representatives were able to understand and sign the informed consent. Exclusion Criteria: * Severe disorder of consciousness: NIHSS 1a consciousness level ≥2 points; * Patients with definite history of intracranial hemorrhage, including parenchymal hemorrhage, intraventricular hemorrhage, subarachnoid hemorrhage, subdural/external hematoma, etc. when screening; * Patients with previously diagnosed intracranial tumor, arteriovenous malformation, or aneurysm when screening; * Patients with bilateral LVO at anterior circulation or LVO at posterior circulation when screening; * Patients with LVO of unknown or rare etiology, e.g., due to dissection, vasculitis, etc. when screening; * Patients who have received treatment with tirofiban, warfarin, novel oral anticoagulants, argatroban, snake venom, defibrase, lumbrokinase or other defibrase therapy after onset, or platelet count \<100×10\^9/L; * Patients with severe hepatic insufficiency or renal insufficiency and received dialysis for various reasons when screening (severe hepatic insufficiency was defined as ALT \> 3 × ULN or AST \>3 × ULN; severe renal insufficiency was defined as serum creatinine \>3.0 mg/dl (265.2 μmol/L) or creatinine clearance \< 30 ml/min); * Patients with previously diagnosed hemorrhagic tendency (including but not limited to): with hereditary hemorrhagic disorders, such as hemophilia, when screening; * Patients with refractory hypertension that is difficult to be controlled by medication (systolic blood pressure \> 180 mmHg or diastolic blood pressure \> 110 mmHg); * Patients with history of major head trauma or stroke within 1 month prior to randomization; * Patients who have received intracranial or spinal surgery within 3 months prior to randomization; * Patients with history of major surgery or serious physical trauma within 1 month prior to randomization; * Patients with previously diagnosed hemorrhagic retinopathy; * Male subjects (or their mates) or female subjects who had planned to have a child during the whole study period and within 3 months after the end of the study period or were unwilling to use one or more non-drug contraceptive methods (e.g., complete abstinence, condoms, ligation, etc.) during the study period; * Patients with contraindications to known contrast agents or other contrast agents; patients who are allergic to Cilostazol or Dexborneol; * Patients who plan to receive other surgical or intervention therapy within 3 months, which might require discontinuation of the study drugs; * Patients with life expectancy of less than 3 months due to advanced stage of comorbidity; * Patients who have received treatment of investigational drugs or devices within previous 3 months; * Other investigator-evaluated conditions which may influence the compliance of patients or where it is not suitable for patients to participate in this trial.