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 Biotheraputics, (OTC:NWBO) finished the trading day with a 12% gain after the company reported excellent early results in its preliminary trials for its DCVax-Direct dendritic cell-based cancer treatment.

So what: Northwest's ongoing clinical trials of DCVax have been targeting patients with inoperable solid tumors. Of the 36 patients in the trial, 19 have completed at least half of the six DCVax treatments (none have made it all the way through the eight-month six-treatment trial period), and of these 19, 11 are showing positive responses. Eight of the 11 patients show signs of tumor necrosis (cell death) and disease stabilization, with biopsies showing "substantial to extensive" tumor necrosis and substantial accumulations of immune cells infiltrating the tumors. Six of those eight patients also showed signs of tumor shrinkage or stabilization, and while the other two patients showed some tumor growth, these enlarged tumors were largely full of dead cells.

The remaining three of the 11 positive-response patients only show signs of stabilization thus far. The remaining eight patients to complete more than half of the treatments are not yet showing any improvement, apparently.

Now what: It's too early to conclude that DCVax-Direct is an unqualified success, but this is certainly very good news for Northwest shareholders, who'd already enjoyed a double this year before shares pulled back in the spring. DCVax is also in other trials under other formulations, as its phase 3 trial for treating brain cancer is currently under way. However, that trial has come under fire in recent months for weak methodology, and the DCVax-Direct trial's small patient sample size should also keep investors from speculating too much on the drug's wider effectiveness. Treat this report with cautious optimism, but make sure you dig deeper into the data before diving in.

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