This is a non-randomized, open-label, Phase I study. A modified Fibonacci dose escalation will be used to determine the MTD for subsequent Phase II trials. Study duration is expected to be 12 to 18 months. Patients with a histological or cytological diagnosis of a solid tumor who have failed standard therapy or for whom no standard therapy exists are enrolled. If there is no dose limiting toxicities and if patients meet the inclusion criteria and have none of the exclusion criteria of the protocol, they will receive further cycles of therapy if there is no evidence of disease progression.