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 biotechnology company InterMune (Nasdaq: ITMN) plunged 17% on Friday after its quarterly results disappointed Wall Street.

So what: InterMune's first-quarter miss was so wide -- EPS loss of $0.74 on revenue of $8.9 million versus the consensus loss of just $0.70 and $10.8 million -- that investors are being forced to lower their valuation estimates yet again. In fact, the stock is busting through its 52-week low on the report and is down a staggering 79% over the past year.

Now what: Despite today's disappointing financial results, InterMune seems happy with the strides that its main drug, Esbriet, is making in Europe. "We are pleased to report that approximately 1,800 patients have initiated Esbriet therapy in Europe to date," Chairman and CEO Dan Welch said, "… underscoring the strong demand for the first approved [idiopathic pulmonary fibrosis] therapy in the European Union." So while InterMune remains just too speculative for average Fools, biotech-savvy investors might want to look into this pullback as a possible turnaround opportunity.

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