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 Amylin Pharmaceuticals (Nasdaq: AMLN) jumped 11% today after the company released great earnings and pipeline news.

So what: During the third quarter, Amylin reported revenue of $175.0 million and a smaller loss per share of just $0.09. Both revenue and earnings per share were significantly better than expected.

Now what: The quarterly numbers were great, but the bigger driver today may have been the announcement that the FDA approved expanded use of BYETTA for diabetes patients. The news today is good, but analysts are still expecting big losses for 2011 and 2012 so this doesn't come close to making the company profitable. Amylin is just too volatile for this Fool to jump in today, and we're just as likely to see shares take a nosedive the next time the FDA gives Amylin bad news.

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