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 (OTC:NWBO), or NW Bio, a predominantly development-stage biopharmaceutical company focused on developing immunotherapies to treat cancer, surged as much as 17% after the company reported additional positive results from its phase 1/2 study involving DCVax-Direct on inoperable solid tumor cancers.

So what: According to NW Bio's early morning press release, all nine patients who have received four of the six planned DCVax-Direct injections are showing some degree of response, including tumor cell death, tumor shrinkage, and immune cell accumulation in their tumors and/or disease stabilization. Furthermore, NW Bio noted that three of these nine patients' tumor biopsies showed no live tumor cells in tumors that had been injected with DCVax-Direct. Wrapping in the company's previously reported data, this means that 13 of 20 patients who have at least received three of six injections have had some degree of disease response to the therapy, ranging from tumor cell death down to disease stabilization. As noted by NW Bio, in all cases only a single tumor in each patient is being injected, although future studies will attempt to inject DCVax-Direct into multiple tumors.

Now what: This is encouraging news, but keep in mind that we're being fed snippets of data and will probably want to hold the champagne uncorking for the end of the study. Given that NW Bio's six-injection treatment involves three injections within the first two weeks, it's no wonder that responses after three injections (just four of 11 patients) seemed fairly tame; frankly, the therapy hasn't been given a lot of time to work. However, following the fourth injection, given during week 8, and prior to a fifth injection in week 16, we're beginning to see the therapy working in select patients. In other words, there's a possibility that the drug's response rate could head even higher as more time passes. Despite this positive data, I'm personally still wary of investing in immunotherapy-focused companies following Dendreon's "failure to launch" with Provenge. However, this data is certainly encouraging enough to add NW Bio to my watchlist for the time being.