Sometimes, it makes sense to bring a product back in-house. That's what The Medicines Company (NASDAQ:MDCO) did this week, when it announced that it will buy back the European rights to its lead drug, anticoagulant Angiomax.

Until now, privately held European specialty pharma Nycomed has marketed Angiomax in Europe. For $20 million in cash this year, $20 million next year, and $5 million in potential milestone payments, Medicines will reacquire its rights to the drug in Europe. The deal is expected to add to earnings in 2009, and the Angiomax European patents are good until 2015.

If Europe represents half of the overall international market for Angiomax and Medicines can meet its goal of $90 million to $110 million in international sales of the drug by 2011, then reacquiring the European rights to the drug for up to $45 million sounds like a steal, considering that European sales could be $45 million to $55 million by 2011.

Reaching this guidance may be difficult, though. Medicines is estimating international sales of Angiomax to fall below the $20 million mark for all of 2008 and for European procedure growth of angioplasties to be just north of 10%. So it will take a big marketing ramp-up and label expansions for Medicines to more than quadruple the drug's sales in the next four years. 

One also wonders why, if the European market for Angiomax is full of so much potential, Nycomed would be willing to part with the rights so cheaply. It could be that sales of the drug don't seem to be faring as well as expected this year, with Medicines this week reducing its U.S. sales guidance range for Angiomax by $16 million. The company also reduced its international guidance range by $3 million to $5 million, although that reduction is due to reduced inventory stock on Nycomed's part. 

The cost of launching a European sales force will probably be in the low-double-digit millions. The Medicines Company is flush with nearly $200 million in cash, so this expansion won't hurt its balance sheet. But whether the expenditure makes sense in the long run all comes down to how well The Medicines Company does in promoting the drug.

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Fool contributor Brian Lawler does not own shares of any company mentioned in this article. The Fool has a disclosure policy.