Trial of Palbociclib in Second Line of Advanced Sarcomas With CDK4 Overexpression.

Non-randomized, open, two-cohort, phase II, multicenter national clinical trial. 20 sites in Spain. Cohort 1 includes soft-tissue sarcoma and osteosarcoma (21 patients), while Cohort 2 includes chordoma patients only (19 patients). Palbociclib will be administered orally at a dose of 125 mg once a day for 21 consecutive days followed by 7 rest days to comprise a complete cycle of 28 days. Treatment will continue until disease progression, development of unacceptable toxicity, non-compliance, withdrawal of consent by the patient or investigator decision. The main goal is to determine progression-free survival rate (PFSR) according to RECIST 1.1 at 6 months.