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: Momenta Pharmaceuticals (NASDAQ:MNTA) shares surged by more than 10% earlier Thursday, just two days after reporting lower-than-expected fourth-quarter sales and profit. Shares closed Thursday up 3% from the previous day's close.

So What: The generic-drug and biosimilars company markets a generic formulation of the cardiology drug Lovenox, and is developing a slate of generic biosimilars that could eventually compete for billions of dollars in revenue as high-priced biologics lose patent protection.

During the fourth quarter, Momenta's sales totaled $21.4 million. However, the majority of those sales -- some $16.4 million -- came from collaboration revenue paid by Baxter International (NYSE:BAX) under the terms of the companies' agreement to develop a biosimilar for AbbVie's (NYSE:ABBV) Humira and Bristol-Myers Squibb's (NYSE:BMY) Orencia.

In addition to that collaboration revenue, Momenta also reported that it received $4.7 million in royalties from Novartis' (NYSE:NVS) Sandoz generic unit in the quarter under the terms of its agreement with Sandoz on sales of generic Lovenox.

Momenta also updated investors on its spending, reporting that R&D expenses totaled $26.2 million in the quarter, and general and administrative expenses were $11.1 million. Since the company's expenses continue to outpace its revenue, the amount of cash on Momenta's books slipped from $245.7 million exiting December 2013 to $191.5 million coming out of 2014.

Now what: Lovenox royalties were essentially flat year over year due to lower prices, and collaboration revenue could fall in 2015. Baxter has decided to opt out of collaborating on Momenta's Orencia biosimilar, and has chosen not to expand its agreement to include other biosimilars outside of Humira. As a result, Momenta expects that its cash-burn rate will reach $30 million in the first quarter.

Momenta is seeking a new collaborator on its Orencia biosimilar, and there is the potential that the FDA will approve its biosimilar of Teva Pharmaceutical's (NYSE:TEVA) multibillion-dollar multiple sclerosis blockbuster Copaxone this year. An application for its Copaxone biosimilar has been submitted by Momenta's development partner Novartis; however, Teva's legal maneuvering has delayed an FDA decision. Overall, the market potential for biosimilars is arguably massive, and that suggests that Momenta could benefit long term -- especially if it can offset its costs through new collaborations.