Momenta Pharmaceuticals (Nasdaq: MNTA) registered its second year of profitability last year. The biotech brought in $283 million in revenue last year, and since its partner Novartis (NYSE: NVS) covers the sales and manufacturing of enoxaparin -- their generic version of Sanofi's (NYSE: SNY) Lovenox -- most of that revenue trickled through to the income line. The company had an operating margin of 63%, which is pretty impressive even for a drugmaker.

Too bad all good things must come to an end.

Momenta and Novartis' enoxaparin became a blockbuster generic -- literally, it sold more than $1 billion in a year -- because Lovenox was already a multibillion-dollar drug and the duo had no competition for 18 months. Recently, though, Sanofi launched an authorized generic, and Watson Pharmaceuticals (NYSE: WPI) and Amphastar launched their version of enoxaparin.

That's a triple whammy for Momenta, losing market share and pricing power as a monopoly. Plus, its agreement with Novartis shifts from a profit share to a royalty.

Since the launch of the second generic just occurred, Momenta wasn't willing to ponder a guess as to how much in royalties it might get from Novartis this year. The only guidance was that it expects to report a net loss in the second through fourth quarters of next year. In the first quarter, Momenta plans to close its deal with Baxter (NYSE: BAX) to develop biosimilars, which will result in a $33 million upfront payment.

While Momenta is back to its losing ways, it's not in quite as bad a shape as your typical development-stage drugmaker since it will have royalty revenue coming in to cover some of its expenses. And with the Baxter payment, Momenta plans on exiting the first quarter with $400 million in the bank, which should give it a nice runway to get another drug approved, hopefully before needing to go back to the markets to raise more capital.

While you're waiting for Momenta to turn back to profitability, take a look at what Fool analysts believe is the next rule-breaking multibagger. Get the free report by clicking here.