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 Biogen Idec (NASDAQ:BIIB) spiked 11% this morning after its multiple sclerosis drug Tecfidera won regulatory protection in Europe.

So what: The European Medicines Agency's Committee for Medicinal Products for Human Use determined that Tecfidera qualifies as a new active substance, extending Biogen's patent protection on the drug and removing a huge cloud of uncertainty over the stock. In fact, according to RBC Capital Markets analyst Michael Yee, Biogen should be able to generate peak sales of $1.2 billion before its exclusivity expires in 2024.

Now what: Don't expect the momentum to slow anytime soon.

"We are ready to introduce TECFIDERA in EU countries shortly after anticipated approval," said Biogen Vice President of Research and Development Douglas Williams. "This designation validates the tremendous investment we have made in TECFIDERA and enables us to invest in future research focused on reversing the course of MS and hopefully one day finding a cure for patients."

Of course, with Biogen stock having now doubled from its 52-week lows, I'd wait for some of the exuberance to fade before buying into that bullishness.