Photo courtesy of AstraZeneca
Results of the SOCRATES trial suggest that ticagrelor is about as safe and effective as aspirin for patients with acute ischemic stroke or transient ischemic attack.
The incidence of the study’s primary endpoint—a composite of stroke, myocardial infarction, and death at 90 days—was similar between the aspirin and ticagrelor arms.
Likewise, there was no significant difference between the arms with regard to safety endpoints.
These results were published in NEJM. The trial was funded by AstraZeneca, which markets ticagrelor as Brilinta.
SOCRATES was a double-blind, controlled trial that enrolled 13,199 patients with a nonsevere ischemic stroke or high-risk transient ischemic attack. The patients had not received intravenous or intra-arterial thrombolysis and were not considered to have had a cardioembolic stroke.
Within 24 hours of symptom onset, the patients were randomized to receive ticagrelor (n=6589) or aspirin (n=6610).
Patients received ticagrelor at a loading dose of 180 mg on day 1, followed by 90 mg twice daily for days 2 through 90. Patients received aspirin at 300 mg on day 1, followed by 100 mg daily for days 2 through 90.
Overall, the differences in baseline characteristics between the treatment arms were not significant. The exceptions were the proportions of patients with a history of diabetes (higher in the ticagrelor arm) or hypertension (higher in the aspirin arm; P<0.05 for both).
The study’s primary endpoint was the occurrence of stroke, myocardial infarction, or death within 90 days. This endpoint occurred in 6.7% of patients in the ticagrelor arm and 7.5% of those in the aspirin arm. The hazard ratio (HR) was 0.89 (P=0.07).
One percent of patients in the ticagrelor arm died, as did 0.9% of patients in the aspirin arm (HR=1.18, P=0.36). The rates of myocardial infarction were 0.4% and 0.3%, respectively (HR=1.20, P=0.55).
The rates of all stroke were 5.9% and 6.8%, respectively (HR=0.86, P=0.03), and the rates of ischemic stroke were 5.8% and 6.7%, respectively (HR=0.87, P=0.046).
The researchers said the P values for all stroke and ischemic stroke were considered nonsignificant in accordance with the hierarchical testing plan used in this study.
Major bleeding occurred in 0.5% of patients in the ticagrelor arm and 0.6% of patients in the aspirin arm (HR=0.83, P=0.45).
Intracranial hemorrhage occurred in 0.2% and 0.3% of patients (HR=0.68, P=0.30), respectively. And fatal bleeding occurred in 0.1% of patients in both arms.
