Phase I
* Three eligible patients will be enrolled at each dose level (DL), according to standard dose escalation decision rules
* Patients will receive CP-4055 at increasing DLs until the maximum tolerated dose and the recommended dose (RD) have been established
Phase II
* Step 1 (The patient inclusion may stop after this step):
* Patients will be enrolled at the RD until there are maximum 16 evaluable patients at this DL
* Step 2:
* Depending on the response rate at step 1, up to 26 patients will be included and treated at step 2
