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 Amarin (NASDAQ:AMRN), a biopharmaceutical company focused on the development of therapies to treat cardiovascular diseases, dipped as much as 10% after announcing after the bell yesterday that the Division of Metabolism and Endocrinology Products had delayed its decision on Vascepa's special protocol assessment.

So what: Shares of Amarin had actually rallied quite significantly yesterday in anticipation of this decision, which was expected by Jan. 15. But DMEP pushed the decision back indefinitely, although the implication from Amarin is that it doesn't expect the delay to last very long. The special protocol assessment for Amarin ANCHOR trial was rescinded in October, and this is the company's last-ditch attempt to get it reinstated. If not reinstated, it appears Amarin will have no choice but to run a confirmatory safety and efficacy study on Vascepa if it has any hope of widely expanding its indicated uses.

Now what: Some investors will speculate the delay is a good thing because the DMEP is looking very closely at the issue, while others might view this news as putting off an inevitable uphold of the FDA's previous decision. Personally, I don't see the ultimate SPA decision having much effect on Amarin's share price. I don't see how Amarin's going to expand Vascepa's usage into the bread-and butter high-triglyceride category without running an additional cardiovascular trial, which in all likelihood is going to take three years. This means Amarin is unlikely to be profitable any time soon and, without a partner, could struggle to generate enough cash to keep its operations going through the end of that trial. I'm staying firmly planted on the sidelines.

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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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