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 Peregrine Pharmaceuticals (NASDAQ:PPHM), a biopharmaceutical company developing monoclonal antibodies to treat cancer, jumped as much as 19% after the company reported final data on its mid-stage second-line non-small cell lung cancer drug, Bavituximab, at the annual American Society of Clinical Oncology meeting.

So what: According to Peregrine's presentation at ASCO, Bavituximab devliered a median overall survival of 11.7 months in combination with docetaxel compared to just 7.3 months for the control arm. Additional studies also demonstrated slight improvements in overall response rate -- 17.1% for Bavituximab and 11.3% for the control arm -- and a 0.3 month improvement in median progression-free survival over the placebo. The data also suggested that Bavituximab was well-tolerated with a similar adverse events profile to that of the control arm.

Now what: If you've been following Peregrine, you're probably well aware of what a roller coaster that its phase 2 trial was. First the data was a knockout success, then it wasn't to be relied upon, and now it's a success again! Peregrine recently had the Food and Drug Administration lend its approval to the company's late-stage trial strategy and will begin enrolling patients shortly. Given the uncertainty that unfolded during phase 2 trials, I considered this late-stage trial the make-or-break one for Peregrine. Personally, though, I'd suggest keeping your distance, as small-cap biotechs don't have the best track record in producing successes in late-stage cancer trials.

Craving more input? Start by adding Peregrine Pharmaceuticals to your free and personalized Watchlist so you can keep up on the latest news with the company.

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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