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What: Shares of Idenix Pharmaceuticals (Nasdaq: IDIX) have popped today by upwards of 18% after the company reported positive trial data on its hepatitis C drug.

So what: Idenix said a mid-stage trial of its drug candidates IDX184 and IDX719 saw positive results in 89% of patients that completed 12-week treatments. CEO Ron Renaud said that the company is looking forward to initiating interferon-free DAA combination studies in the near term.

Now what: The hepatitis C drug market is huge, so it's not surprising when good news like this boosts the company as much as it has. The market is expected to grow to $15 billion by 2019, which is largely why companies looking to get in on the ground floor have fared relatively well in recent times. If Idenix can grab just a piece of that pie, it will be just fine.

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