Multicohort Trial of Trabectedin and Low-dose Radiation Therapy in Advanced/Metastatic Sarcomas

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 overall response rate (ORR) in the irradiated nodules according to RECIST v1.1 criteria. Treatment Medication Trabectedin at 1.5 mg/m2 24-h IV CI along with radiation therapy (30 Gy, 3 Gy/day for 10 days for non-extremity location and 45 Gy, 1.8 Gy/day for 25 days for extremity location of target lesion(s)), starting within 1 hour after the first trabectedin infusion withdrawal (day 2)) will be given every 3 weeks up to progression or intolerance. Premedication 4 mg oral dexamethasone 24h and 12h before trabectedin administration, 20 mg IV dexamethasone 30 minutes before treatment. Ondansetron or analogue will also be given prior to trabectedin.