Background: The TNKCAT trial represents an innovative approach to optimize timely reperfusion in the Mothership and Drip-and-Ship scenarios. The logistic advantage of a single bolus infusion of TNK (compared to 1-h infusion of tPA) would markedly reduce the needle-to-groin and Door-in- door-out time. The implementation of a quality improvement package (QIP) in the TNKCAT trial would directly improve the quality and efficiency of the Health Care System. In addition, an improvement of transfer models would reduce the cost of unnecessary transfers, together with the fact that TNK is up to 50% less expensive than tPA, makes the TNKCAT in firm line with the sustainability strategy of the National Health Care system.

Outcomes: The aim of the present study is to determine the safety and efficacy of TNK (0.25mh/kg) compared to tPA (0.9 mg/kg) in patients with Large Vessel Occlusion (LVO) suspicion, candidates for thrombectomy, in both Mothership and Drip-and-Ship scenarios.

Study Duration: 2 years. Patients will participate in the trial for 3 months.

Study design: Multicentre, prospective, randomized open-label blinded endpoint (PROBE) phase III study in acute stroke patients with LVO suspicion within 4.5 hours of stroke onset, candidates for EVT. Patients will be randomized 1:1 to standard dose tPA (0.9 mg/kg) or TNK (0.25mg/kg) before EVT.

Clinical, imaging and outcome data will be collected at baseline, 24-36 hours, day 3, day 5 and day 90.

Estimated enrollment: 500 patients

Inclusion Criteria:

• Patients eligible to undergo intravenous thrombolysis (tPA or TNK) within 4.5 hours after the onset of ischemic stroke.
• Suspicion of Cerebral vascular occlusion on brain imaging.
• Age >18 years old
• Men and women (women with child-bearing potential are excluded, unless pregnancy test negative/ confirmed menstrual period/ postmenopausal or hysterectomy).
• A new focal disabling neurologic deficit consistent with acute cerebral ischemia.
• Informed consent obtained from subject or acceptable subject surrogate (i.e. next of kin, or legal representative), or Differed Inform Consent (DIC) to avoid any delay in the initiation of iv thrombolysis. The DIC will be sign by the patient or next of kin at any time after the tPA or TNK treatment is started.

Exclusion criteria:

• Patients with severe preexisting disability, defined as a modified Rankin scale score >3.
• Glasgow Coma Scale score ≤ 7.
• Known hemorrhagic diathesis, coagulation factor deficiency, or antivitamin K oral anticoagulant therapy with INR >3.0. Subjects on factor Xa inhibitors (e.g. apixaban) or direct thrombin inhibitors are eligible for participation.
• Severe, sustained and uncontrollable hypertension (systolic blood pressure >185 mmHg or diastolic blood pressure >110 mmHg).
• Serious, advanced, or terminal illness with anticipated life expectancy of less than 3 months.
• Patients that are unlikely to be available for a 90-day follow-up (e.g. no fixed home address, visitor from overseas).
• Patient participating in a randomized study, involving an investigational drug or device that would impact this study.
• Suspicion of aortic dissection presumed septic embolus, or suspicion of bacterial endocarditis.

Imaging exclusion criteria:

• Clinical symptoms suggestive of bilateral stroke or stroke in multiple territories.
• Cerebral vasculitis.
• CT or MRI evidence of hemorrhage
• Significant mass effect with midline shift.
• Evidence of intracranial tumor.
• Subjects with known occlusions in multiple vascular territories (e.g., bilateral anterior circulation, or anterior/posterior circulation).

Clinical outcome at day 90 will be obtained by centralized telephone call of the mRS in a blinded manner by certified personnel of the Catalan Stroke Program.