Tenecteplase for Acute Ischemic Stroke Within 4.5 to 6 Hours of Onset (EXIT-BT2)

To date, the benefit of intravenous thrombolysis is confined within 4.5 hours of onset for acute ischemic stroke (AIS) patients without advanced neuroimaging selection. Unpublished pilot EXIT-BT (EXtending the tIme window of Thrombolysis by ButylphThalide up to 6 Hours after onset) suggest the safety, feasibility and potential benefit of intravenous tenecteplase (TNK) in AIS within 4.5 to 6 hours of onset. The current study aims to investigate the efficacy and safety of TNK for AIS within 4.5 to 6 hours of onset.

Inclusion Criteria: * Age ≥ 18 year * Acute ischemic stroke confirmed by non-contrast computed tomography and use of CTA for assessment of LVO as determined by local investigators; * The time from last known well to treatment: 4.5 - 6 hours; * NIHSS ≥ 4 at randomization; * First stroke onset or past stroke without obvious neurological deficit (mRS≤1); * Uncertainty over the benefits and risks of thrombolysis by researcher; * Signed informed consent. Exclusion Criteria: * Pre-stroke disability (mRS≥2); * Planned intravenous thrombolysis based on WAKE-UP or EXTEND study criterion; * Any contraindication to intravenous thrombolysis: Obvious head injury or stroke within 3 months; Subarachnoid or intracranial hemorrhage; History of intracranial hemorrhage; Intracranial tumor, arteriovenous malformation or aneurysm; Intracranial or spinal cord surgery within 3 months; Myocardial infarction within 3 months; Major surgery within 1 month; Gastrointestinal or urinary tract hemorrhage within the previous 30 days; Arterial puncture at a noncompressible site within the previous seven days; Active internal hemorrhage; Coagulation abnormalities: platelet count of \1.6 or APTT abnormal; Systolic pressure ≥185 mmHg or diastolic pressure ≥110 mmHg; Blood glucose \< 50 mg/dl (2.7mmol/L); Neurological deficit after epileptic seizures; * Pregnancy; * Allergy to test drugs; * Comorbidity with other serious diseases; * Participating in other clinical trials within 3 months; * Patients not suitable for the study considered by researcher.