<qa>  What was the first time the subjects were admitted to the clinical research center of Seoul National University HospitalOnly healthy volunteers had screening tests such as medical inquiry, physical examination, clinical laboratory test, etc. within 4 weeks -28d -1d prior to drug administration 1d and those determined eligible for this study were selected and randomized between screening and 1 day prior to the first administration of study medication -1d. Then, the subjects were admitted to the clinical research center of Seoul National University Hospital by 9 p.m. of -1d and then, they were not allowed to take anything except water. 