The purpose of the RCT trial is to evaluate whether implantation of drug-eluting stent (DES) is more efficacious than bare metal stent (BMS) in prevention of in-stent restenosis (ISR) and improvement of outcomes for symptomatic intracranial atherosclerotic stenosis. This trial is prospective, multi-center, randomized 1:1 single blind trial using Maurora sirolimus eluting stent versus Apollo bare metal stent conducted in approximately 10 interventional neurology centers in China. The study is sponsored by Alain Medical (Beijing) Co., Ltd.

This trial is a prospective, multi-center, 1:1 randomized using drug-eluting (Sirolimus) stent versus bare metal stent (BMS) to treat intracranial stenosis of 70-99% degree. The primary endpoint is in-stent restenosis rate(ISR) within 12 months after revascularization procedure of the qualifying lesion during follow-up.

Inclusion Criteria:

1. Age from 18 to 80 years;
2. Symptomatic intracranial atherosclerosis (Definition: Stroke or transient ischemic attack [TIA] associated with intracranial atherosclerosis within 90 days of enrollment);
3. A major intracranial artery (carotid artery, MCA stem [M1], vertebral artery, or basilar artery) with 70% to 99% stenosis on the angiography (According to WASID method);
4. The target lesion length ≤15 mm and the vessel diameter between 2.5mm and 5.0mm, distal vessel diameter >1.5mm;
5. Only one stent planned for the target lesion;
6. A Modified Rankin Score of ≤ 3;
7. Patients understand the purpose and requirements of the study, and can make him/herself understood, and has provided informed consent.

Exclusion Criteria:

1. Ischemic stroke within 2 weeks before the procedure;
2. Tandem extracranial or intracranial stenosis (70%-99%) of the target lesion;
3. Patients with stroke caused by perforating artery occlusion;
4. Severe calcification at target lesion;
5. Any history of brain parenchymal or other intracranial subarachnoid, subdural or extradural hemorrhage in the past 6 weeks;
6. History of stenting or angioplasty of an intracranial artery;
7. Intracranial tumor, aneurysm or intracranial arteriovenous malformation;
8. Intracranial artery stenosis caused by non-atherosclerotic lesions, including: moya-moya disease, vasculitis disease, herpes zoster, varicella-zoster or other viral vascular diseases, neurosyphilis, any other intracranial infections, radiation-induced vascular disease, fibromuscular dysplasia, sickle cell disease, neurofibromatosis, central nervous system benign vascular disease, post-partum vascular disease, suspected vasospasm, suspicious embolism recanalization;
9. Presence of any unequivocal cardiac source of embolism (e.g. atrial fibrillation);
10. Those who cannot tolerate general anesthesia due to insufficiency of cardiac or pulmonary function, not suitable for procedure;
11. Known allergy or contraindication to heparin, aspirin, ticlopidine, ticagrelor, sirolimus, anaesthetics and contrast agents;
12. Severe renal and hepatic insufficiency (ALTor AST > 3x upper limit, creatinine > 1.5x upper limit);
13. Major surgery within the past 30 days or planned within 90 days, or requiring simultaneous intervention to renal artery, iliac artery, and coronary artery;
14. Life expectancy <12 months;
15. Pregnant or lactating women, or planning for pregnancy;
16. Participated in another investigational device or drug study within 30 days;
17. According to the judgement of the investigator, other situations that are not suitable for enrollment.