This study is comprised of 2 sequential parts: Part 1 (Dose Escalation of VS-5584) and Part 2 (Expansion). Up to 56 evaluable subjects (i.e., subjects who complete at least 1 cycle \[21 days\] of therapy) will be enrolled, assuming that:
* Up to 6 dose levels of VS-5584 are studied in Part 1 (Dose Escalation of VS-5584) in combination with a fixed dose of VS-6063 at 400 mg twice daily (BID) with a maximum of 6 subjects enrolled per VS-5584 dose level, for a total of up to 36 subjects (exclusive of replacement subjects).
* Up to an additional 20 evaluable subjects may be enrolled in Part 2, the expansion portion of the study. Subjects will be treated with VS-5584 at the RP2D and schedule determined in the dose escalation portion of the study in combination with a fixed dose of VS-6063.
