According to the Global Burden of Disease(GBD) Study 2016, China bears the greatest lifetime risk of stroke from 25-year-age onward. Minor ischemic events, including minor stroke and TIA, were major parts of stroke manifestations. Events (CHANCE) has shown that 21-day dual antiplatelet therapy (clopidogrel and aspirin) compared to aspirin alone which initiated within 24 hours after symptoms onset would reduce 32% risk of stroke recurrence within 90 day, but not in carriers of CYP2C19 loss-of-function (LOF) alleles. The primary purpose of this study is to compare ticagrelor plus aspirin with clopidogrel plus aspirin on reducing the 3-month risk of any stroke (both ischemic and hemorrhagic, primary outcome) when initiated within 24 hours of symptom onset in CYP2Y19 LOF alleles carriers with TIA or minor stroke.~Both intent analysis (ITT) and compliance program set (PPS) were used for analysis.~We will use Kaplan-Meier estimates of the cumulative risk of stroke (ischemic or hemorrhagic) event during maximum 90-day follow-up, with hazards ratios and 95% CI calculated using Cox proportional hazards methods and the log-rank test to evaluate the treatment effect. All statistics will be 2-sided with P<0.05 considered significant, accounting for interim analyses.~All patients who received study drugs and with at least one safety follow-up record will be included in the safety population. The data for safety evaluation included adverse reactions observed during the trial and changes in laboratory data before and after treatment.
The primary objective of this trial is to assess the effects of ticagrelor plus aspirin versus clopidogrel plus aspirin on reducing the 3-month risk of any stroke (both ischemic and hemorrhagic, primary outcome) when initiated within 24 hours of symptom onset in CYP2Y19 LOF alleles carriers with TIA or minor stroke.