Oncolytics Biotech announces new reovirus, cyclophosphamide research

Oncolytics Biotech Inc. has reported that a research group led by Dr. Richard Vile of the Mayo Clinic College of Medicine in Rochester, Minnesota, published the results of its work testing the antitumor efficacy and safety of various combinations of reovirus and cyclophosphamide in vivo.

The paper, entitled “Cyclophosphamide Facilitates Antitumor Efficacy against Subcutaneous Tumors following Intravenous Delivery of Reovirus” appears online in the January 1, 2008 issue of Clinical Cancer Research.

“This exciting Mayo Clinic work supported the initiation of our combination REOLYSIN® and cyclophosphamide clinical trial, recently approved by the U.K. health authorities,” said Dr. Matt Coffey, Chief Scientific Officer of Oncolytics.

The purpose of the research study was to investigate whether it was possible to use cyclophosphamide, an immune modulator, to enhance the delivery and replication of the reovirus when delivered intravenously. After testing various doses and dosing regimens of reovirus and cyclophosphamide in mice, a metronomic dosing regimen was developed that resulted in increased survival, high levels of reovirus recovered from regressing tumors, levels of neutralizing antibodies that were protective, and only very mild toxicities. The data support investigation in human clinical trials of the use of cyclophosphamide prior to systemic reovirus administration to modulate, but not ablate, the immune system.