Brad Thompson, CEO of Oncolytics Biotech, said it was really exciting for him to see CBS'60 Minutes drawing attention to virus-based cancer treatments a couple weeks back. However, he said that there is a lot more involved when it's about treating a disease.

The episode surrounded an engineered polio virus being developed at Duke University to treat glioblastoma, a deadly form of brain cancer. Thompson's company was founded in 1998 on discoveries made at the University of Calgary about the cancer-killing prowess of reovirus.

A couple of years later, the company went public on the Toronto Stock Exchange and Nasdaq. The company that time was conducting early phase I trials of its reovirus-based therapy for head and neck cancer. The therapy was called Reolysin.

The stock of Oncolytics Biotech is now just 75 cents a share because of continuous failure of Reolysin trials in head and neck cancers. But is has not shattered the confidence of Thompson for reovirus and about polio and the many other virus-based immunotherapy treatments being tried in oncology.

Oncolytics's approach was different from what researchers are doing at Duke. Reovirus has a natural ability to spare normal cells and replicate into tumor cells that contain genetic mutations in a pathway called Ras. After replication is started by the virus, tumor cells are killed and the virus begins travelling to nearby tumors to do the same. Researchers found that initial ability of reovirus was not good enough to kill tumor cells because of lack of power, but it did well by interacting with the immune system, boosting it to continue killing cancer cells over the long term.

But the problem is immune system does not have as good access to the head and neck cancers as to other cancers.