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What: Shares of Dendreon (NASDAQ:DNDN), a biopharmaceutical company focused on developing cancer immunotherapies, surged as much as 14% after the European Commission approved its advanced prostate cancer immunotherapy, Provenge, for marketing.

So what: This really shouldn't come as a surprise here as the Committee for Medicinal Products for Human Use (the EU's version of our FDA panel) recommended Provenge for marketing approval in late June. The marketing authorization was granted based on a 737-patient late-stage study where median overall survival in the Provenge arm increased 4.1 months relative to the placebo. This approval gives Dendreon the right to sell Provenge in all 28 countries of the EU.

Now what: Now for the real challenge: Will it sell? In the U.S., Provenge sales have been going in reverse in 2013 thanks to tougher metastatic prostate cancer competition and higher costs, which have been difficult for Dendreon to keep under control. With Dendreon cutting jobs and administrative expenses, coupled with this approval, there is hope that Dendreon's cash burn rate will shrink dramatically. However, without a marketing partner or differentiable factor that makes Provenge the go-to medication, it could still be difficult for Dendreon to separate itself from the pack and move toward profitability.

Fool contributor Sean Williams has no material interest in any companies mentioned in this article. You can follow him on CAPS under the screen name TMFUltraLong, track every pick he makes under the screen name TrackUltraLong, and check him out on Twitter, where he goes by the handle @TMFUltraLong.

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