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 Alkermes (NASDAQ:ALKS), a diversified biopharmaceutical company, rose as much as 16% after the company announced positive clinical results for ALKS-5461 in a mid-stage trial to treat major depressive disorder, or MDD.

So what: The oral, non-addictive, opioid modulating drug was tested on 142 patients with MDD that had not responded to the current standard of treatment. In trials, the ALKS-5461 arm met its primary endpoint of changing the baseline in depressive symptoms over a four-week period as defined by the Hamilton Depression Rating Scale. The release also notes that the drug was well-tolerated. Alkermes plans to meet with the Food and Drug Administration soon in an attempt to advance ALKS-5461 into a development program.

Now what: I definitely believe that Alkermes shareholders have more than enough reason to turn those frowns upside down today! Rumblings on Wall Street are that, if approved, ALKS-5461 could have a market opportunity around $500 million. However, I'd forecast considerably more upside given the current one-size-fits-all nature of depression medications. As long as Alkermes can demonstrate non-dependence and a similar safety profile to existing depression medications, it could have a good shot at gaining approval since the results so far have spoken for themselves.

Craving more input? Start by adding Alkermes 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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