Summary: Phase II, multicohort, single arm, open-label, multicenter, international clinical trial with three cohorts (cohort A: Soft tissue sarcoma, cohort B: Bone tumors (osteosarcoma, chondrosarcoma and cohort C: Small round-cell sarcomas (Ewing's sarcoma, rhabdomyosarcoma, desmoplastic small round-cell tumors and other small round cell sarcomas)) with 7 sites in Spain.~Main objective: To evaluate the ov...