Number of Events/Number in Cohort Action 0/3 Proceed to next dose level 1/3 Accrue 3 more patients at the same dose 1/3 + 0/3 Proceed to next dose level 1/3 + 1/3 Stop: Previous dose level is MTD 1/3 + 2/3 Stop: Previous dose level is MTD 1/3 + 3/3 Stop: Previous dose level is MTD 2/3 Stop: Previous dose level is MTD 3/3 Stop: Previous dose level is MTD