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 drug research contractor Parexel International (Nasdaq: PRXL) plummeted 20% today after its quarterly results and full-year guidance failed to meet Wall Street's lofty expectations.

So what: Thanks to weak revenue at its early stage business, client delays, and a big number of projects still in start-up, Parexel posted a third-quarter profit of just $15.7 million, or $0.26 per share, versus the average analyst estimate of $0.30 per share. Given the stock's 30%-plus run-up over just the past three months, it's no surprise that investors are readjusting their expectations in a big way on the poor results.

Now what: Today's 20% plunge might be worth taking advantage of. Along with the results, management announced plans to restructure its early stage segment in response to the disappointing quarter and also cut its full-year sales and profit guidance well below analyst forecasts. But with the stock now trading at a PEG of just over one, Parexel might be a reasonably priced long-term growth recovery story.

Interested in more info on Parexel? Add it to your watchlist.

Fool contributor Brian Pacampara owns no position in any of the companies mentioned. Try any of our Foolish newsletter services free for 30 days.

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