Cilostazol in Acute Ischemic Stroke Treatment (CAIST Trial): A Randomized Double-Blind Non-Inferiority Trial

<i>Background:</i> Aspirin is a proven antiplatelet agent in acute ischemic stroke, and there are no current guidelines for other antiplatelet treatments. We aimed to compare the efficacy and safety of cilostazol with aspirin in acute stroke. <i>Methods:</i> Patients with measurable neurological deficits (NIHSS score ≤15) within 48 h of onset were randomly assigned to cilostazol (200 mg/day) or aspirin (300 mg/day) for 90 days. The primary endpoint was a modified Rankin Scale (mRS) score of 0–2 at 90 days. Cardiovascular events, bleeding complications, and other functional outcomes were also assessed. Statistical analysis was carried out by intention-to-treat and per-protocol bases. This trial is registered with ClinicalTrials.gov (NCT00272454). <i>Results:</i> In total, 458 patients were enrolled (mean age of 63 years, median NIHSS of 3), and mRS at 90 days was obtained in 447 patients. The primary endpoint was achieved in 76% (173/228) of those randomized to cilostazol and in 75% (165/219) assigned to aspirin, which supported the pre-specified non-inferiority of cilostazol to aspirin (95% CI of proportion difference: –6.15 to 7.22%, p = 0.0004). These results were also supported by per-protocol analysis (p = 0.045). Cardiovascular events occurred in 6 patients (3%) treated with cilostazol, and in 9 patients (4%) treated with aspirin (p = 0.41). Adverse events were more common in cilostazol-treated patients during the trial (91 vs. 85%, p = 0.055), while the frequencies of bleeding complications (cilostazol 11%, aspirin 13%, p = 0.43) or drug discontinuation (cilostazol 10%, aspirin 7%, p = 0.32) were not different. <i>Conclusion:</i> Cilostazol is feasible in acute ischemic stroke, and comparable to aspirin in its efficacy and safety.