A Single-Arm Trial of Neurovascular Drug-Eluting Balloon Dilatation Catheter Treating Symptomatic Intracranial Atherosclerotic Stenosis

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.