For cohorts 2, 3, 4, and 5, If none of the first three patients experiences a DLT, the next three patients will be enrolled in next higher dose cohort. If one of the first three patients in the first cohort experiences DLTs, an additional three patients will be enrolled into that cohort. If 2 or 3 of the first 3 patients experience DLTs, then the previous cohort will be considered the MTD and up to an additional 10 patients will be enrolled at that dose in Part 2 of the study.