This is a single center, open study. The aim of the trial is the definition of the maximum tolerated dose (MTD) for future phase 2 studies. Secondary endpoints include the overall response rate, the time-to-progression and the assessment of the pharmakokinetic of the compound. The trials follows a canonical 3+3 design and allows an additional recruitment of up to 6 patients on the dose level defined as the MTD. Planned dose levels are as follows: