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What: Shares of PTC Therapeutics (NASDAQ:PTCT), a biopharmaceutical company focused on developing oral small-molecule drugs designed to treat serious and life-threatening diseases and disorders, dipped as much as 17% after PTC today provided an update on the opinion of the Committee for Medicinal Products for Human Use, or CHMP, for ataluren as a treatment for nonsense mutation Duchenne muscular dystrophy, or nmDMD. However, shares rebounded ended the trading day nearly 3% in the green.

So what: According to a PTC Therapeutics press release, the European Medicines Agency committee has adopted a negative opinion on the company's marketing authorization application for ataluren as a treatment for nmDMD. As the press release states, this opinion isn't a surprise, as the company is still conducting a confirmatory phase 3 trial that will encompass 220 patients and take 48 weeks. Top-line data from this study is expected by mid-2015. PTC still intends to request a reexamination of the CHMP's opinion next quarter.

Now what: The press release pretty much tells you everything you need to know as an investor: the CHMP has a negative opinion on ataluren at the moment; this wasn't a surprise at all given PTC's previously cautious guidance on a marketing authorization approval in Europe; and that it'll simply move forward with its late-stage trial. Other than the fact that PTC's shares have shot to the moon lately and today's news simply gave shareholders a reason to take a few dollars off the table, this CHMP opinion didn't really change the scope of ataluren's development much, if at all.

PTC shares may have doubled in just two months, but it still may have a hard time keeping pace with this top stock in 2014!
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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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