Consenting, eligible healthy adult subjects sequentially received either gemigliptin 50 mg q.d., metformin 1000 mg twice a day or gemigliptin 50 mg q.d. plus metformin 1000 mg twice a day during 3 consecutive 7 day treatment periods separated by two 5-day washout intervals, in accordance with a randomly assigned treatment sequence. Starting on the sixth treatment period day, participating subjects underwent safety assessments and repeated (24 hour) blood and urine sampling for pharmacokinetic analysis. All subjects attended to a post-study visit for final safety assessments within 8 days of study completion or early withdrawal.