• Objective response rate [ Time Frame: Week 24, and every 12 weeks thereafter ] [ Designated as safety issue: No ]
• Progression-free survival in patients with Ewing's sarcoma [ Time Frame: Week 18 ] [ Designated as safety issue: No ]

• Duration of response, PFS. [ Time Frame: Week 18 ] [ Designated as safety issue: No ]
• Overall PFS. [ Time Frame: Event driven ] [ Designated as safety issue: No ]
• Overall objective response rate, response duration, overall PFS and overall survival in patients with Ewing's sarcoma. [ Time Frame: Event driven ] [ Designated as safety issue: No ]

This single arm study will evaluate the efficacy and safety of R1507 in patients with recurrent or refractory sarcoma. Five cohorts of sarcoma patients will be studied in parallel: Ewing's sarcoma, osteosarcoma, synovial sarcoma, rhabdomyosarcoma, and other sarcomas. All patients will receive R1507 9mg/kg i.v. weekly. The anticipated time on study treatment is until disease progression or unacceptable adverse events, and the target sample size is 100-500 individuals.

Inclusion Criteria:

• patients >=2 years of age;
• progressive, recurrent or refractory Ewing's sarcoma, or recurrent or refractory osteosarcoma, synovial sarcoma, rhabdomyosarcoma, or other sarcomas of the following sub-types: alveolar soft part sarcoma, desmoplastic small round cell tumor, extraskeletal myxoid chondrosarcoma, clear cell sarcoma and myxoid liposarcoma.

Exclusion Criteria:

• clinically significant unrelated systemic illness which would compromise the patient's ability to tolerate the investigational agent, or interfere with the study procedures or results;
• known hypersensitivity to any of the components of R1507 or prior hypersensitivity reactions to monoclonal antibodies;
• current or previous treatment (within last 6 months) with chronic pharmacological doses of corticosteroids, immunosuppressive agents or medications that inactivate or may interfere with the pharmacological activity of R1507;
• current or prior therapy with IGF inhibitor (monoclonal or specific kinase inhibitor);
• history of solid organ transplant;
• other malignant disease diagnosed within the previous 5 years, excluding intra-epithelial cervical neoplasia or non-melanoma skin cancer.