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 Idenix Pharmaceuticals (NASDAQ: IDIX), a biopharmaceutical company focused on developing therapies to treat hepatitis-C, grew wings and flew higher by as much as 11% after reporting its second-quarter earnings results.

So what: For the quarter, Idenix reported total revenue of $112,000 (not surprising, as it is entirely a clinical-stage biopharmaceutical company) and a net loss of $0.22 per share. Comparatively speaking, investors couldn't care less about Idenix's lack of revenue at this point, but they have to be pleased with its loss of just $0.22 per share when a loss of $0.23 was forecast. The biggest impetus for the move higher, though, appears to be the company's synopsis of its pipeline, which includes the initiation of a mid-stage trial for its lead drug, samatasvir, in May, as well as reminding shareholders that while IDX20963 is on clinical hold in the U.S., it is nonetheless continuing the drug's development in overseas markets.

Now what: Today's results certainly could have been much worse, but I can't say I'm particularly intrigued with Idenix here, even well off its 52-week high. Idenix's novel drugs have fallen well behind its peers, Gilead Sciences and AbbVie, in terms of bringing revolutionary new hepatitis-C treatments to market. With three clinical holds under its belt in just over the past year initiated by the FDA, it just might have the worst luck in the biotech sector. I don't think Idenix is a stock that investors can trust until it proves it can move one of its hep-c programs out of mid-stage trials.

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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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