The STem Cell-derived Extracellular Vesicle Therapy In Acute Ischemic Stroke (STEVIA)

Inclusion Criteria:

• Adults with 19 years or older

• Patients within 5 days of symptom onset who have not received thrombolytic therapyor undergone endovascular reperfusion procedures.

• Patients within 5 days of symptom onset who have received thrombolytic therapy orundergone endovascular reperfusion procedures but show no clinical recovery after 2days of observation.

• Imaging findings must meet both of the following:

• Infarction within the middle cerebral artery territory on diffusion-weightedimaging (DWI)

• Infarct size ≥ 20 mm in the longest diameter on DWI

• Neurological status meeting all three of the following NIHSS criteria:

• Moderate to severe neurological deficit (NIHSS score between 5-21)

• New onset of motor weakness (score 2-4 in at least one of NIHSS items 5a, 5b, 6a, or 6b)

• No impaired consciousness (score 0-1 on NIHSS items 1a, 1b, and 1c)

• Voluntary written informed consent

Exclusion Criteria:

Subjects are ineligible if they meet any of the following:

• Pre-stroke disability (pre-stroke mRS ≥ 2)

• Likely to recover spontaneously, based on all three of:

• No longer meeting the NIHSS inclusion criteria 48 hours post-thrombolysis orendovascular therapy

• Lacunar stroke due to small vessel occlusion

• SAFE (Shoulder Abduction and Finger Extension) score ≥ 5

• Presence or risk of malignant middle cerebral artery infarction with brain edema

• Significant medical history within the past 5 years:

• Severe heart failure

• Severe infectious disease

• Severe hepatic failure or renal failure

• Newly diagnosed or actively treated cancer

• Any systemic disease deemed by investigator to significantly reduce lifeexpectancy

• Any condition likely to hinder follow-up during the study

• Diagnosed severe psychiatric illness:

• Moderate or greater depression pre-stroke with functional impairment andsuicide risk

• Pre-stroke dementia interfering with daily living (CDR ≥ 2)

• Contraindication to MRI (e.g., pacemaker)

• Pregnant or breastfeeding, or unwilling to use effective contraception method for 90days after last dose.

• Participation in another clinical trial within the past 3 months

• Any other reason determined by the investigator that would prevent participation