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: Questcor Pharmaceuticals (Nasdaq: QCOR) shares jumped 10% early Friday on news the company received Food and Drug Administration approval for H.P. Acthar Gel.

So what: H.P. Acthar Gel treats seizures in infants, an extremely rare disorder that affects about 2,000 children in the U.S. annually. Questcor is also getting a seven-year exclusivity period to market the drug.

Now what: This clears up concerns over the FDA's extended review, which drove shares down in September. Questcor shares are up close to 100% over the last year, so I would be careful buying into this rally. There could be a better long-term buying opportunity if you can wait for excitement over this news to die down.

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