One reason immunotherapies fail is because of the ability to tumors to alter the microenvironment in which they exist and hide themselves from detection by the immune system. In some indications, as few as 20 percent of patients benefit from checkpoint inhibitors. Oncolytics Biotech is developing pelareorep, an immune-oncolytic virus that activates the innate and adaptive immune systems, triggering inflammation in the tumor, and overexpressing checkpoints to increase the number of patients that can benefit from the use of checkpoint inhibitors. We spoke to Matt Coffey, president and CEO of Oncolytics Biotech, about Pelareorep, how it works to treat cancer, and why it can make checkpoint inhibitors more effective.