Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of Agenus (NASDAQ:AGEN), a clinical-stage biopharmaceutical company focused on developing immuno-oncology therapies, jumped as much as 26% this morning after announcing the final overall survival results from its phase 2 study involving its Prophage vaccine for patients with newly diagnosed glioblastoma multiforme , or GBM, the most aggressive form of brain cancer.

So what: According to its press release, Prophage patients exhibited a median overall survival of 24 months, with a third of patients still alive and being studied post treatment. By comparison, this median overall survival was close to double that of the current standard of treatment which includes the combination of Temodar and radiation. Adding icing on the cake, Agenus also notes that Prophage vaccinated patients demonstrated median progression-free survival of 18 months which ranged between two-to-three times longer than the current standard treatment. Additionally, 22% of patients were alive and without progression at the 24-month mark per Agenus. Management believes this data provides the impetus to move forward to a larger study with Prophage.

Now what: I wasn't exactly swooning over Agenus' HerpV data last week, but the survival data for Prophage in the difficult-to-treat GBM indication does have me excited. I'm actually a bit shocked that shares retraced a bit from their highs and aren't up more (how often do you hear me say that?). If Agenus wasn't on your watchlist before, it pretty much has to be on your watchlist now, following these incredible survival statistics. Of course, we should keep in mind this was a phase 2 study and we'll need to see how well these results translate into a larger phase 3 audience. However, if future late-stage study results are even remotely close to doubling in median overall survival, compared to the current standard of treatment, then Agenus could have a big hit on its hands.