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 PTC Therapeutics (NASDAQ:PTCT), a biopharmaceutical company developing small-molecule drugs to treat cancer, neuromuscular disorders, and infectious diseases, dropped as much as 15% after reporting its fourth-quarter results after the closing bell last night.

So what: For the quarter, PTC Therapeutics reported a 34% decline in revenue to $4.4 million as both collaboration and grant revenue fell from the year-ago quarter. Total operating expenses, however, soared by 77% to $22.5 million due to the initiation of its confirmatory phase 3 trial involving ataluren in patients with nonsense mutation Duchenne muscular dystrophy (nmDMD), as well as higher general and administrative expenses. The combination of lower revenue and higher expenses ballooned its net loss to $17.9 million, or $0.75 per share, from $6.3 million in the fourth quarter of 2012. By comparison, Wall Street anticipated a much narrower loss of $0.57 per share.

Looking ahead, PTC Therapeutics is forecasting total operating expenses of $85 million-$95 million in fiscal 2014, and plans on ending the year with $175 million-$185 million in cash, cash equivalents, and marketable securities.

Now what: Generally speaking, earnings reports tend to be non-events for clinical-stage biopharmaceutical companies. But considering how far PTC's share price has run and how quickly it could burn through its cash if its losses continue to surpass the Street's forecast, the move lower today does make sense. The big event that has share-moving potential for PTC won't be coming until mid-2015. That's when PTC Therapeutics will be releasing the top-line data from its 48-week confirmatory trial using ataluren for nmDMD. Shareholders might find the lack of catalysts leading up to this data to be few and far between, but this is, nonetheless, where investors' focus should remain.

PTC Therapeutics shares have soared over the past few months, but it may be no match to keep pace with this top stock in 2014
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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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