What: Shares of Northwest Biotherapeutics (OTC:NWBO), a small-cap clinical biotech company with a focus on immuno-oncology, are down more than 16% today on news of a phase 3 clinical trial halt for the company's lead compound.

So what: According to the EU clinical trial register, the company's current phase 3 clinical trial that is evaluating DCVas-L as a treatment for Glioblastoma multiform, a lethal brain cancer, is currently listed as "temporarily halted". 

As of 1:30 today, the company has yet to comment on the trial's status with a press release, and investors are selling the stock hard as a result of the news

Now what: As DCVax-L is the company's compound that is furthest along in development, the news of the trial being halted is a worrisome sign for investors. Although the company boasts a few other trials currently under way, it will still be years before any of them could possibly find there way to market.

Source: Northwest Biotherapeutics

In addition the company's cash position is really starting to get tight as it reported only slightly more than $19 million in cash on its balance sheet as of June 30th, and yet the company lost more than $38 million last quarter from operations alone. Total net loss for the quarter actually landed at more than $66 million when you include the change in fair value of its derivative liability position.

This once high flying company has been an awfully tough stock to hold for a long time, as shares are now down more than 99% since hitting the public markets more than a decade ago.

Given the long-term underperformance of this stock and the company's current precarious cash position, I'm more than content to keep my investment dollar far aware from this stock.