A Phase II Study Evaluating Efficacy and Safety of Regorafenib in Patients With Metastatic Bone Sarcomas

INDICATION: Metastatic bone sarcomas: conventional high grade osteosarcoma, Ewing sarcoma of bone, intermediate or high-grade chondrosarcomas and chordomas and either bone or soft tissue metastatic CIC-rearranged sarcomas

Inclusion Criteria: 1. Patients must have histologically confirmed diagnosis of bone sarcoma (osteosarcoma, Ewing sarcoma of bone, chondrosarcoma or chordoma); 2. Patients with confirmed disease progression at study entry; 3. Metastatic disease not amenable to surgical resection or radiation with curative intent; 4. Patients must have measurable disease; 5. Prior treatment : at least one, but no more than two prior chemotherapy regimen for metastatic disease for osteosarcoma, chondrosarcoma and Ewing sarcoma; neo-adjuvant /maintenance therapy are not counted towards this requirement. Chordoma not pretreated or with 1 or 2 prior (combination) chemotherapy regimen or with one or two prior molecularly targeted therapy, but no more than 2 prior lines of treatment (whatever the indication) can be included. At least 4 weeks since last chemotherapy (6 weeks in case of nitrosoureas and mitomycin C), immunotherapy or any other pharmacological treatment and/or radiotherapy; 6. Age ≥10 years for osteosarcomas, Ewing sarcomas and chondrosarcomas (for chordomas, patients must be ≥18 years); 7. Body Surface Area ≥1.30 m²; 8. Life expectancy of greater than 3 months; 9. Eastern Cooperative Oncology Group (ECOG) performance status \12 years old / Lansky scale ≥60% for children aged ≤12 years old; 11. Patients must have adequate bone marrow, renal, and hepatic function, as evidenced by the following within 7 days of study treatment initiation: normal organ function as defined below: * Absolute neutrophil count ≥1.5 Giga/L * Platelets ≥100 Giga/L * Hemoglobin ≥9 g/dL * Serum creatinin ≤1.5 x upper limit of normal (ULN) * Glomerular filtration rate (GFR) ≥30 ml/min/1.73 m² according to the modified Diet in Renal Disease (MDRD) abbreviated formula * Aspartate transaminase (AST) and alanine transaminase (ALT) ≤2.5 x ULN * Bilirubin ≤1.5 X ULN * Alkaline phosphatase ≤2.5 x ULN (≤5 x ULN in patient with liver involvement of their cancer). If Alkaline phosphatase \>2.5 ULN, hepatic isoenzymes 5-nucleotidase or gamma-glutamyl transferase (GGT) tests must be performed; hepatic isoenzymes 5-nucleotidase must be within the normal range and/or GGT \