This is a multicenter, randomized, double-blind, placebo-controlled clinical trial (SLEDAIS) involving 1,040 patients with acute ischemic stroke (AIS) who require inter-hospital transfer for potential endovascular therapy. The study aims to evaluate the efficacy and safety of sublingual Edaravone Dexborneol tablets administered in the ultra-early stage (within 6 hours of symptom onset) during the critical inter-hospital transfer window.

Patients will be randomly assigned in a 1:1 ratio to receive either sublingual Edaravone Dexborneol (a loading dose of 4 tablets initially, followed by 1 tablet twice daily for 13 days) or a matching placebo. The primary efficacy endpoint is the functional outcome assessed by the modified Rankin Scale (mRS) score at 90 days. The primary safety endpoint is the mortality rate at 90 days. This study seeks to provide high-quality evidence for neuroprotection during the transfer period, potentially improving functional recovery for stroke patients.

Inclusion Criteria:

• Aged 18 to 80 years (inclusive).
• Time from last known normal to arrival at the first hospital is within 6 hours.
• Clinical and imaging diagnosis of acute ischemic stroke, with a Los Angeles Motor Scale (LAMS) score ≥ 4, or occlusion of the internal carotid artery, M1/M2 segment of the middle cerebral artery, V4 segment of the vertebral artery, or basilar artery confirmed by CTA/MRA at the first or target hospital.
• ASPECTS score ≥ 6 on non-contrast head CT at the first hospital.
• Clinically assessed as planned for immediate transfer to a target hospital for evaluation of endovascular therapy (final decision on whether to perform EVT is made by the neuro-interventionist at the target hospital based on imaging and clinical status).
• Written informed consent signed by the patient or their legal representative.

Exclusion Criteria:

• Allergy to contrast agents, nickel, titanium, or their alloys.
• Known allergy to dexborneol, edaravone, or excipients.
• Pre-stroke modified Rankin Scale (mRS) score ≥ 2.
• Patients receiving intravenous thrombolysis alone.
• Severe impairment of consciousness (e.g., GCS score < 8) or inability to cooperate with sublingual administration.
• Severe hepatic or renal insufficiency (e.g., ALT/AST > 3 times the upper limit of normal, Cr > 2 times the upper limit of normal).
• Estimated inter-hospital transfer time > 3 hours.
• Pregnant or lactating women.
• Arterial tortuosity and/or other arterial diseases where the thrombectomy device is expected to be unable to reach the target vessel.
• Brain tumors with mass effect on imaging (except small meningiomas).
• Currently participating in other drug clinical trials.
• History of neurological or psychiatric diseases that hinder the assessment of neurological function.
• Any late-stage disease with an expected life expectancy < 6 months.