To evaluate the safety and efficacy of the Medeliver® Intracranial Drug-Coated Balloon Catheter (developed by Beijing Jiu Shi Shen Kang Medical Technology Co., Ltd.) in the endovascular treatment of symptomatic intracranial atherosclerotic stenosis.

Inclusion Criteria:

1. Age 18-80 years;
2. Symptomatic intracranial arterial stenosis within the past 6 months, with 70%-99% diameter stenosis on angiography (per WASID criteria);
3. Target lesion located in: intracranial segment of the internal carotid artery (C3 or above), M1/M2 segment of the middle cerebral artery, basilar artery, or intracranial segment of the vertebral artery;
4. At least one atherosclerotic risk factor (history or current hypertension, diabetes mellitus, hyperlipidemia, hyperhomocysteinemia, smoking, or alcohol consumption);
5. Reference vessel diameter adjacent to the target lesion ≥ 2 mm；
6. Baseline mRS score ≤ 2;
7. Patient or legally authorized representative understands the study purpose, voluntarily agrees to participate, provides written informed consent, and is willing and able to comply with follow-up visits.

Exclusion Criteria:

1. Acute ischemic stroke within 2 weeks prior to screening;
2. Major surgery or acute myocardial infarction within 30 days prior to screening;
3. Intracranial hemorrhage (parenchymal, subarachnoid, subdural, or extradural) within 3 months prior to screening;
4. Uncontrolled hypertension despite medical therapy (systolic BP ≥ 180 mmHg or diastolic BP ≥ 110 mmHg);
5. Coexisting intracranial tumor, intracranial aneurysm requiring treatment, or arteriovenous malformation;
6. Previous stenting of the target lesion or any intracranial stenting/endovascular procedure within the past 3 months;
7. Cardioembolic stroke;
8. Stroke caused solely by perforator artery occlusion;
9. Two or more consecutive lesions with ≥ 70% stenosis in the target vessel;
10. Additional de novo or in-stent restenosis lesions (> 70% diameter stenosis);in other intracranial arteries requiring treatment during the same session;
11. Severe calcification, extreme angulation, severe tortuosity, or other anatomical features in the target vessel that may prevent safe device delivery or retrieval;
12. Known allergy or contraindication to heparin, sirolimus (rapamycin), iodinated contrast, aspirin, clopidogrel, or local anesthetics;
13. Gastrointestinal bleeding within 6 months prior to informed consent, rendering antiplatelet therapy unsafe;
14. Platelet count < 90 × 10⁹/L;
15. INR > 1.5;
16. Pregnant, breastfeeding, or planning pregnancy within 1 year;
17. Life expectancy < 1 year;
18. Participation in another drug or device clinical trial currently or planned during the study period;
19. Intracranial stenosis due to non-atherosclerotic etiology (e.g., arterial dissection, moyamoya disease, vasculitis, active arteritis, thrombosis);
20. Severe or unstable comorbidities (e.g., severe heart failure, respiratory failure, renal failure [serum creatinine > 3.0 mg/dL or 264 µmol/L], severe hepatic impairment [ALT/AST > 3 × ULN], active malignancy);
21. Flow-limiting dissection or residual stenosis > 50% after pre-dilatation;
22. Any other condition that, in the investigator's judgment, makes the patient unsuitable for enrollment;