 This is a phase 1, single ascending dose study to evaluate the PK and safety of AG-221 in healthy adult male Japanese subjects relative to healthy adult male Caucasian subjects. A total of 60 subjects will be enrolled; 30 will be Japanese subjects and 30 will be Caucasian subjects. There will be a total of 3 cohorts. Cohort A will receive a single dose of 100 mg AG-221. Cohort B will receive a single dose of 50 mg AG-221. Cohort C will receive a single dose of 300 mg AG-221. Within each cohort, 10 subjects will be Japanese and 10 subjects will be Caucasian. 