Intra-arterial TNK Following Endovascular Thrombectomy in Patients With Large Vessel Occlusion of Posterior Circulation

Inclusion criteria * Acute ischemic stroke patients with symptomatic intracranial large vessel occlusion (LVO) in the intracranial vertebral artery, basilar artery, or the P1 segment of the posterior cerebral artery. * Treated with endovascular thrombectomy (EVT) resulting in an eTICI score 2b50/3 at end of the procedure. * Age of 18 years or older; * National Institutes of Health Stroke Scale (NIHSS) score on admission≥6; * Posterior Circulation ASPECTS ≥ 6 on CT/CTA-Source Images/MRI-DWI. * Time from estimated time of basilar artery occlusion to randomization\<24 hours; * Written informed consent. Exclusion criteria * Pre-existing dependency with mRS \>1; * Contraindication to Intravenous Thrombolysis (except time to therapy); * Complete clinical recovery in the angiography suite by end of EVT procedure; * Pregnancy; if a woman is of childbearing potential a urine or serum beta HCG test is positive; * Severe contrast allergy or absolute contraindication to iodinated contrast; * Participation in other investigational drug or device clinical trials; * Systolic pressure \>185 mmHg or diastolic pressure \>110 mmHg, and cannot be controlled by antihypertensive drugs; * Known genetic or acquired bleeding diathesis, lack of anticoagulant factors, or oral anticoagulant drugs and INR \> 1.7, or treated with direct oral anticoagulant agents in the prior 48 hours; * platelets \<100 000/mm3, aPTT \>40 s, or PT \>15 s; Blood glucose \< 2.7 or \>22.2 mmol/L; * Severe renal Failure as defined by a serum creatinine \> 3.0 mg/dl (or 265.2 μmol/l) or glomerular Filtration Rate \[GFR\] \< 30, or patient requires hemodialysis or peritoneal dialysis; * Clinical presentation suggests a subarachnoid hemorrhage, even if initial CT or MRI scan is normal; * Suspicion of aortic dissection; * Presumed vasculitis or septic embolization; * Life expectancy \< 1 year; * Patients that cannot complete 90-day follow-up (e.g. no fixed residence, overseas patients, etc.)； * CT/MR shows intracranial hemorrhage; * Ischemic stroke within 3 months; * Severe head trauma within 3 months; * Major surgery or severe trauma within the last 2 weeks. * History of prior intracranial hemorrhage.