The SAMMPRIS trial compared aggressive medical management alone with aggressive medical management plus percutaneous transluminal angioplasty and stenting (PTAS) using the Wingspan stent system in patients with intracranial arterial stenosis. The primary endpoint was stroke or death within 30 days after enrollment or during follow-up, or stroke in the territory of the qualifying artery beyond 30 days. Enrollment was stopped after 451 patients were randomized due to higher-than-expected stroke rates in the PTAS group (14.7% at 30 days) compared to the medical-management group (5.8%). Beyond 30 days, stroke rates were similar in both groups. The 1-year probability of the primary endpoint was 20.0% in the PTAS group and 12.2% in the medical-management group. The results suggest that aggressive medical management is superior to PTAS with the Wingspan stent system, likely due to the high risk of periprocedural stroke in the PTAS group and the lower-than-expected stroke rate in the medical-management group.The SAMMPRIS trial compared aggressive medical management alone with aggressive medical management plus percutaneous transluminal angioplasty and stenting (PTAS) using the Wingspan stent system in patients with intracranial arterial stenosis. The primary endpoint was stroke or death within 30 days after enrollment or during follow-up, or stroke in the territory of the qualifying artery beyond 30 days. Enrollment was stopped after 451 patients were randomized due to higher-than-expected stroke rates in the PTAS group (14.7% at 30 days) compared to the medical-management group (5.8%). Beyond 30 days, stroke rates were similar in both groups. The 1-year probability of the primary endpoint was 20.0% in the PTAS group and 12.2% in the medical-management group. The results suggest that aggressive medical management is superior to PTAS with the Wingspan stent system, likely due to the high risk of periprocedural stroke in the PTAS group and the lower-than-expected stroke rate in the medical-management group.