Oncolytics Biotech was up as much as 12% today after announcing a successful phase 2 metastatic melanoma trial for its cancer drug Reolysin, which is based on a common virus. 

In this video, health-care analyst David Williamson explains what this trial success means for Oncolytics and why the market is skeptical, and he discusses another virus-based cancer drug from a Big Pharma stock that investors may want to put on their radars.

David Williamson has no position in any stocks mentioned. Follow David on Twitter: @MotleyDavid.

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