Oncolytics Biotech Inc. has been granted U.S. Patent 6,994,858 entitled "Reovirus Clearance of Ras-Mediated Neoplastic Cells from Mixed Cellular Compositions."
The claims describe methods of using the reovirus ex vivo to eliminate contaminating cancer cells from autologous (harvested from the patient themselves) blood stem cell transplants. The results of a study to purge cancer cells from autologous stem cell preparations using the reovirus were previously published in the March 13, 2003 issue of Blood.
"The results of this study demonstrated that the reovirus may have a role to play in purging contaminating cancer cells from stem cell preparations used for transplants," said Dr. Matt Coffey, Chief Scientific Officer for Oncolytics. "This patent provides Oncolytics with an important extension of the potential use of the reovirus for the treatment of cancer."
Hematological (derived from blood) stem cell rescue following high-dose chemotherapy is extensively used clinically for both solid tumours and tumours of the blood. Globally, the number of autologous blood and bone marrow transplants surpasses the number of donor-derived transplants. It has been estimated that as many as 30 per cent of these autologous stem cells transplants are contaminated by cancer cells, and may contribute to clinical relapse of the cancer.