The purpose of this study is to assess the safety, tolerability, pharmacokinetics and pharmacodynamics of single doses of FYU-981 administered orally to healthy male adults in fasted and fed conditions. Participants are randomized to placebo (n=3) or FYU-981 (n=6) in each step. After follow-up examination in the step of lower dose, the next dose is administered. The effect of food on PK/PD of FYU-981 is also investigated.