Intracranial atherosclerosis stenosis (ICAS) accounts for up to 30-50% of strokes amongst Asian patient cohorts, in contrast to 5-10% of strokes amongst western patient cohorts. The SAMMPRIS established aggressive medical management (dual antiplatelet therapy using asprin and clopidogrel, intensive management of vascular risk factors, and lifestyle modification) as a superior choice for symptomatic ICAS compared to the percutaneous transluminal angioplasty and stenting. However, around 15% still had recurrent stroke or death during a median follow-up of 32.4 months in SAMMPRIS study in the aggressive medical management group.~Rivaroxaban is a Non-vitamin K antagonist oral anticoagulant (NOAC) that Directly and selectively inhibits factor Xa. 2019 European Society of Cardiology (ESC) recommended that adding rivaroxaban (2.5mg twice a day) to aspirin for long-term secondary prevention in patients with chronic coronary syndromes (post-myocardial infarction >1 year) may be considered (IIB). 2020 ESC also recommended the adding of rivaroxaban (2.5mg twice a day for 1 year) to aspirin plus clopidogrel in acute coronary syndrome (IIB).~The proposed study will directly compare rivaroxaban on top of aspirin with clopidogrel on top of asprin for preventing recurrent stroke/TIA and death in recent stroke/TIA patients with ICAS.~The investigators calculated that a sample of 1180 patients (590 in each arm) would provide 80% power to detect a relative risk reduction of 35% in the ravaxaban-aspirin group, with a two-sided type I error of 0.05, assuming an event rate of 15% in the clopidogrel-aspirin group and a 5% overall rate of withdrawal.~Baseline features of the two groups were compared with the use of an independent group t-test (for means) or chi-square test (for percentages). Analysis of primary and secondary outcomes was based on Kaplan-Meier estimates of cumulative incidence. All analyses were performed on an intention-to-treat basis, unless specified otherwise. All tests were two-sided, and a P value of 0.05 was considered to indicate statistical significance. All statistical analyses were performed with the use of SPSS software.
The primary goal of the clinical trial is to test the effect of oral rivaroxaban plus aspirin in patients with recent stroke/ transient ischemic attack (TIA) caused by intracranial artery stenosis. Participants will be divided into 2 groups to receive either oral rivaroxaban plus aspirin or oral clopidogrel plus aspirin. The main question it aims to answer is whether the experimental group (oral rivaroxaban plus aspirin) is superior to the control group ( oral clopidogrel plus aspirin) to lower recurrent stroke/TIA or death in these patients during 1 year of follow-up.