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: ViroPharma Inc. (Nasdaq: VPHM) shares fell 10% on Friday after the FDA declined expansion plans for Cinryze.

So what: The FDA declined industrial-scale manufacturing of Cinryze, which treats a fatal genetic disorder called hereditary angioedema. Regulators are looking for more information after observations at pre-approval inspections and a review of the process.

Now what: The company still plans to move forward with higher production assuming risk moving forward. After pummeling the stock 17% in pre-market trading, the stock is up significantly on the day. The risks seem minimal going forward, so barring further setbacks I view this dip as a short-term buying opportunity.

Interested in more info on ViroPharma? Add it to your watchlist here by clicking here.

Fool contributor Travis Hoium does not have a position in any company mentioned. You can follow Travis on Twitter at @FlushDrawFool, check out his personal stock holdings or follow his CAPS picks at TMFFlushDraw.

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