REO 014 was an open-label, single agent Phase II study of REOLYSIN® in patients with bone and soft tissue sarcomas metastatic to the lung who had been deemed by their physicians to be unresponsive to or untreatable by standard therapies. These included patients with osteosarcoma, Ewing sarcoma family tumours, malignant fibrous histiocytoma, synovial sarcoma, fibrosarcoma and leiomyosarcoma. Patients received intravenously-administered REOLYSIN® on days 1 through 5 of each twenty-eight day cycle. Fifty-two patients were enrolled in the study. The primary objective was to assess tumour response by RECIST criteria. The secondary objective was safety.
Results from the study were presented by Oncolytics collaborators at the 15th Annual Connective Tissue Oncology Society Meeting in November 2009. The investigators reported that the treatment had been well tolerated to date, and that 19 of 44 evaluable patients experienced stable disease ranging from two to 20 months, resulting in a total clinical benefit rate (complete response plus partial response plus stable disease) of 43%. The response objective for the study was three or more patients having prolonged stabilization of disease (6 months or better). The trial exceeded this objective, with six patients experiencing stable disease for more than six months. Two patients experienced stable disease for more than 19 months, one of whom had synovial cell sarcoma that had relapsed following surgery, while the other had Ewing’s Sarcoma and had previously progressed following multiple treatments.