Subsequent dose escalation will occur in a similar fashion. If a subject discontinues treatment for reasons other than study drug related adverse events such that safety cannot be fully evaluated, an additional subject may be enrolled; these will be reviewed on a case-by-case basis in conjunction with the Sponsor. The dose will be escalated until either a MTD is identified or the maximum dose, 310 mg/m2/day, is achieved. Ten additional subjects will be enrolled at the MTD to better define toxicity and to better evaluate efficacy at the MTD.