Eligibility for participation of this study was determined from demographic information, medical history, physical examination, electrocardiogram (ECG) and clinical laboratory tests within 4 weeks before study drug administration. Subjects suitable for this study were admitted to the Clinical Trials Center, Samsung Medical Center on the day before dosing, and they were overnight-fasted from 10 p.m. of Day -1. Subjects were dosed simvastatin 40 mg orally around at 9 a.m. of Day 1. Subjects performed scheduled procedures including clinical laboratory tests and pharmacokinetic samplings for simvastatin. Subjects were dosed cilostazol 100 mg in the morning on Day 2 and discharged, and visited Clinical Trials Center on Day 3, Day 4 and Day 5 for the oral administration of cilostazol 100 mg. Subjects was admitted in the evening on day 5 and dosed simvastatin 40 mg plus cilostazol 100 mg concomitantly and scheduled pharmacokinetic sampling for simvastatin was performed. Next morning (Day 7), subjects were discharged