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 NewLink Genetics Corp. (NASDAQ:NLNK), a clinical-stage developer of immunotherapy treatments to fight cancer utilizing its proprietary HyperAcute immunotherapy technology platform, advanced as much as 12% after presenting positive study data on its immunotherapy candidates at the European Cancer Congress.

So what: According to NewLink's press release, the company's HyperAcute immunotherapy candidates demonstrated "greater than expected responses to salvage chemotherapy following treatment with both algenpantucel-L in patients with pancreatic cancer and tergenpumatucel-L in patients with non-small cell lung cancer (NSCLC)." Specifically, NewLink notes that three pancreatic cancer patients exhibited durable complete responses of 12 to 36 months after having progressed on algenpantucel-L therapy. Of the 16 NSCLC patients, 25% achieved stable disease while 31% demonstrated a partial response.

Now what: This is definitely good news, but I feel that investors would be wise not to get too excited just yet. We're talking about extremely early-stage immunotherapy candidates and small pool studies. If these results translate into statistically significant improvement in a much larger trial, then I feel we need to consider NewLink as a viable investment option. For the time being, it's watchlist worthy, but I'd probably suggesting waiting on investing in the company until we have more tangible mid- or late-stage results.

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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