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 MannKind (NASDAQ:56400P706) soared a staggering 80% on Wednesday after a Food and Drug Administration advisory committee recommended approval of its inhaled diabetes drug Afrezza.

So what: The Endocrinologic and Metabolic Drugs Advisory Committee's recommendation comes about three years after the FDA initially rejected Afrezza on a lack of sufficient clinical data, so today's news naturally serves as a huge relief to investors. While the FDA isn't bound by the committee's decision, it usually does follow its recommendations, putting Afrezza in a prime position to become the first ultra-rapid-acting mealtime insulin in the country's huge diabetes drug market.

Now what: The FDA is expected to make its final approval decision on Afrezza by April 15. "We look forward to working with the FDA as they complete their evaluation of AFREZZA," said MannKind Chairman and CEO Alfred Mann in a press release. "Diabetes is a major health problem in the United States, and we are committed to bring AFREZZA to the many patients who might benefit from this novel product." When you couple today's massive rally with the uncertainty that continues to surround Afrezza's commercial potential, however, risk-averse Fools would probably do well to keep watching from the sidelines.