This is a trial designed to test the efficacy and safety of the Neurovascular Drug-Eluting Balloon Dilatation Catheter.

This is a prospective multicentre single-arm trial conducted by 11 centers in mainland China. Approximately 132 subjects with symptomatic intracranial atherosclerotic stenosis receive endovascular treatment using the neurovascular drug-eluting balloon dilatation catheter designed by Zylox.

Inclusion Criteria:

• Age 18 to 80 years, any gender;
• Subject has symptomatic intracranial atherosclerotic stenosis that the degree of the artery stenosis is between 70% and 99% diagnosed by intracranial angiography;
• The target stenotic artery locates in Internal Carotid Artery (intracranial segment), Middle Cerebral Artery (M1, M2), Basilar Artery, Vertebral Artery (intracranial segment);
• Intracranial artery stenosis requiring interventional treatment is a single lesion;
• Subject has at least two atherosclerosis risk factors including history or present hypertension, diabetes, hyperlipidemia, smoking, age>45;
• modified Rankin Scale(mRS) score≤2 before enrollment;
• Subject or guardian is able to understand the purpose of study, agree to provide follow-up data and has provided written informed consent.

Exclusion Criteria:

• History of acute ischemic stroke within 2 weeks;
• History of intracranial hemorrhage (including intraparenchymal hemorrhage, subarachnoid hemorrhage, subdural hemorrhage and epidural hemorrhage) within 3 months;
• Hypertension uncontrolled by medicine (Systolic pressure≥180 mmHg or diastolic pressure≥110 mmHg continuously);
• Combined with the intracranial tumor, aneurysm or intracranial arteriovenous malformation;
• The length of intracranial artery stenosis >10mm and extremely angulated >90°, which indicated by angiography;
• History of stent intervention within the target lesion;
• Allergic to heparin, sirolimus (i.e. rapamycin), contrast agents, aspirin, clopidogrel, anesthetics;
• History of gastrointestinal hemorrhage within 6 months before signing the informed consent form, which is unable to receive antiplatelet therapy;
• Platelet (PLT)<90*10^9/L;
• Creatinine>250 umol/L;
• International Normalized Ratio (INR)>1.5;
• Female subject who is pregnant or breast-feeding, or who has a pregnancy plan within 12 months;
• Expected life <12 months;
• Unable to cooperate with or tolerate the interventional surgery;
• Subject who has participated in other drug or device clinical trials or hasn't reached the primary end point;
• Angiography indicates intracranial artery stenosis caused by arterial dissection, arteritis, and thrombosis;
• Angiography indicates the vascular path is tortuous, the experimental device is difficult to reach the target position or be retracted;
• Other circumstances judged by researchers that are not suitable for enrollment.