Endovascular Treatment for Posterior Circulation Ischemic Stroke Post 1 Day （24 Hours） (ETP1-PC)

Endovascular Treatment for Posterior Circulation Ischemic Stroke Post 1 Day （24 Hours） A Randomized Controlled Clinical Trial On Efficacy

To evaluate the efficacy and safety of endovascular therapy for posterior circulation ischemic stroke presenting more than 24 hours after symptom onset.

Study Overview

• Status: Not yet recruiting
• Conditions: Posterior Circulation Ischemic Stroke
• Intervention / Treatment: Drug: Standard pharmacological treatment; Procedure: Endovascular treatment combined with standard pharmacological treatment

Detailed Description

This study is a multicenter, open-label, blinded-endpoint, randomized controlled trial designed to evaluate the efficacy and safety of endovascular treatment administered beyond 24 hours after the onset of posterior circulation ischemic stroke. A total of 244 patients (122 per group) will be enrolled, aged ≥18 years, with a baseline NIHSS score ≥4, onset of stroke or last known well time >24 hours and within 7 days, and confirmed occlusion of the basilar artery or the intracranial segment of bilateral vertebral arteries as the culprit vessel. Patients will be randomly assigned to the experimental group (endovascular treatment plus standard medical therapy) or the control group (standard medical therapy alone). The primary endpoint is the proportion of patients with a 90-day modified Rankin Scale (mRS) score of 0-3. Secondary endpoints include the distribution of 90-day mRS scores, the proportion of patients with a 90-day mRS score of 0-2, and the 90-day EQ-5D-5L scale score. The study is led by Union Hospital, Tongji Medical College, Huazhong University of Science and Technology as the coordinating center and will be conducted at multiple centers across China, with a planned duration of 36 months.

• Study Type: Interventional
• Enrollment (Estimated): 244
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Bo Hu, Doctor; Phone Number: 13707114863; Email: hubo@mail.hust.edu.cn

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Age ≥ 18 years old
2. Baseline NIHSS score of 4 or higher, maintained prior to randomization
3. Stroke onset or more than 24 hours since the last known good state, but within 7 days
4. CTA/MRA/DSA confirmed occlusion of the responsible vessel in basilar artery or intracranial segments of both vertebral arteries (V4)
5. Modified Rankin Scale (mRS) score of 0 or 1 pre-stroke
6. The subject or their legally authorized representative has signed the informed consent form for the study

Exclusion Criteria:

1. Hemorrhage on CT or MRI
2. Based on the judgment of the treating physician, the patient is considered unlikely to benefit from the trial (e.g., advanced dementia, severe pre-stroke disability (mRS ≥ 2), or high risk of early mortality)
3. Major comorbidities that may interfere with outcome assessment and follow-up (e.g., severe heart failure, renal failure, etc.).
4. Evidence of vascular recanalization prior to randomization
5. Uncontrolled seizures at the time of stroke onset, if they interfere with obtaining an accurate baseline NIHSS
6. Posterior circulation Acute Stroke Prognosis Early CT score (pc-ASPECTS) < 6 on non-contrast CT or CT angiography source images or MR with diffusion-weighted imaging
7. Complete cerebellar infarct with significant mass effect and compression of the fourth ventricle,or bilateral thalamic infarction on CT or MRI
8. Baseline platelet count <50,000/uL
9. Severe, persistent hypertension (systolic blood pressure > 220 mmHg or diastolic blood pressure > 120 mmHg)
10. Known hereditary or acquired bleeding disorders, coagulation factor deficiencies, or recent oral anticoagulant therapy with an International Normalized Ratio (INR) > 3
11. Suspected purulent embolism, with a suspicion of bacterial endocarditis
12. Known allergies to iodine, heparin, anesthetics, or other explicit contraindications to the endovascular treatment procedure
13. Pregnancy
14. Other serious, progressive, or end-stage diseases (as determined by the investigator) or a life expectancy of less than 6 months
15. Attempted use of a neurothrombectomy device to remove the clot prior to randomization
16. Currently participating in a study involving other investigational drugs or devices
17. Evidence of intracranial tumor on CT or MRI (excluding meningioma)
18. CTA/MRA showing excessive tortuosity of the cervical vessels, which may interfere with endovascular treatment
19. Suspicion of aortic dissection based on medical history and CTA/MRA findings
20. Any other conditions that the investigator believes may interfere with the endovascular procedure or pose significant risk to the subject during the procedure

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: control group; Standard pharmacological treatment	Drug: Standard pharmacological treatment; Standard medical therapy: antiplatelet, statin, and vascular risk factor control per stroke guidelines, without endovascular intervention.
Experimental: Test group; Endovascular treatment combined with standard pharmacological treatment	Procedure: Endovascular treatment combined with standard pharmacological treatment; Mechanical thrombectomy (stent retriever or aspiration) plus standard medical therapy (antiplatelet, statin, and risk factor control), specifically for posterior circulation stroke with onset >24 h to ≤7 days.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Proportion of patients with an mRS score of 0-3 at 90 days	90days

Secondary Outcome Measures

Outcome Measure	Time Frame
Stroke-related mortality at 90 days	90days
All-cause mortality at 90 days	90days
Symptomatic intracranial hemorrhage (sICH) (defined as a worsening of NIHSS by 4 or more points within 24 hours after random treatment, associated with intracranial hemorrhage)	24hours
Surgical-related complications	Post procedure 24hours
EQ-5D-5L scale score at 90 days	90days
New onset of stroke within 90 days	90days
Hematoma of any type at 24 hours (-6/+24) after random treatment	24hours
The distribution of mRS scores at 90 days post-randomization	90days
Proportion of patients with an mRS score of 0-2 at 90 days	90days

Collaborators and Investigators

• Sponsor: Union Hospital, Tongji Medical College, Huazhong University of Science and Technology

Study record dates

Study Major Dates

• Study Start (Estimated): August 1, 2026
• Primary Completion (Estimated): August 1, 2029
• Study Completion (Estimated): August 1, 2030

Study Registration Dates

• First Submitted: July 7, 2026
• First Submitted That Met QC Criteria: July 10, 2026
• First Posted (Actual): July 13, 2026

Study Record Updates

• Last Update Posted (Actual): July 13, 2026
• Last Update Submitted That Met QC Criteria: July 10, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Keywords: stroke; Posterior Circulation
• Additional Relevant MeSH Terms: Cerebrovascular Disorders; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Vascular Diseases; Cardiovascular Diseases; Stroke
• Other Study ID Numbers: ETP1-PC

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No