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 Northwest Biotherapeutics (NASDAQ:NWBO), a clinical-stage biopharmaceutical company developing therapies to treat cancer, skyrocketed by as much as 36% after announcing two special approvals in Germany for its lead immunotherapy product, DCVax-L.

So what: According to Northwest Biotherapeutics' press release, under Germany's hospital exemption, and via an approval from the Paul Ehrlich Institute (the equivalent of the Food and Drug Administration in Germany), hospitals can now provide DCVax-L to patients with any type of glioma brain cancers, whether they are newly diagnosed or recurrent, and the company can charge full price for these treatment outside of its ongoing phase 3 clinical studies. Under the terms of the hospital exemption, DCVax-L must be manufactured in Germany, but is free to be given to non-German citizens in German hospitals. The hospital exemption clause has an effective period of five years. The approval itself is remarkable because, in just shy of three years, only two other products have received the "hospital exemption" and none of the prior two exerted a pharmacological effect within the human body. It also expands the use of DCVax-L to all glioma brain cancers, which is a much wider indication than its current U.S. trials.

In addition, Northwest Biotherapeutics also notes that the German reimbursement authority has deemed its DCVax-L treatment eligible for reimbursement from Sickness Funds, which is another term for German health insurers. As expected, only hospitals can apply for reimbursement, and Northwest notes that six hospitals have thus far applied for reimbursement eligibility.

Now what: Clearly, this is a big win for Northwest Biotherapeutics, which has a wholly clinical-stage pipeline at present. It's unclear how much revenue this could provide Northwest in the interim, but Northwest's press release mentions that there are roughly 7,000 newly diagnosed cases of gliomas per year in Germany. This exemption could also go a long way to validating its immunotherapy platform, which uses dendritic cells to educate the immune system to attack cancer cells. Immunotherapy platforms are all the rage on Wall Street right now, so this approval couldn't possibly come at a better time.

Despite the news, I would still suggest existing shareholders be cautious. Historically, small-cap biotech companies with cancer-fighting compounds have a very poor track record of drug approval. In addition, if DCVax-L were to be turned away by the FDA, there would be a steep gap all the way back to its next closest product in development, DCVax-Direct, for solid tumor cancers -- DCVax-Direct is currently only in phase 1/2 trials at the moment. In other words, with a valuation north of $300 million, investors' optimism may be more than priced in following today's news.

Northwest Biotherapeutics may be skyrocketing today, but even it could have a hard time keeping up with this top stock in 2014
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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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