Oncolytics Biotech Inc. Announces Publication of Research on Combination Reovirus and Radiation Therapy

CALGARY, Canada, February 4 /PRNewswire/

Oncolytics Biotech Inc. (TSX: ONC, NASDAQ: ONCY) ('Oncolytics') reported today that Dr. Kevin Harrington and his research group at The Institute of Cancer Research, London, U.K. published the results of their work testing combination treatment schedules of reovirus and radiation in human and murine tumour cells in vitro and in vivo. The paper, entitled "Enhanced In vitro and In vivo Cytotoxicity of Combined Reovirus and Radiotherapy" appears online in the February 1, 2008 issue of Clinical Cancer Research.

The effect of different schedules of reovirus and radiotherapy on viral replication and cytotoxicity was tested in vitro and the combination was assessed in three tumour models in vivo. The results demonstrated that combining reovirus and radiotherapy significantly increased cancer cell killing both in vitro and in vivo, particularly in cell lines with moderate susceptibility to reovirus alone.

"Dr. Harrington's work demonstrates convincingly that REOLYSIN® works to enhance the effects of radiation therapy," said Dr. Matt Coffey, Chief Scientific Officer of Oncolytics. "The results of this preclinical research provided strong support for the combination REOLYSIN® and radiation clinical trials we are conducting in the U.K. To date, we have successfully completed enrolment in a Phase Ia/Ib combination REOLYSIN® and radiation trial and are currently enrolling patients in a Phase II trial using this combination".

From the abstract:

Results: Characterization of reovirus cytotoxicity in a panel of cell lines yielded a range of sensitivities. Combined reovirus and radiotherapy yielded statistically significantly increased cytotoxicity, particularly in cell lines with moderate susceptibility to reovirus alone. The enhanced cytotoxicity of the combination occurred independently of treatment sequence or schedule. Radiation did not affect viral replication and only reduced reoviral cytotoxicity after clinically irrelevant single doses (>50 Gy). Combination index analysis revealed synergy between radiation (3-10 Gy) and reovirus at multiplicities of infection between 0.001 and 1. Combination treatment significantly increased apoptosis in tumor cells relative to either single-agent treatment. In vivo studies using xenograft and syngeneic tumors showed enhanced activity of the combination relative to reovirus or radiation alone (P <>

View the complete abstract here.