British drugs group Shire said Monday that it has agreed to buy US-based ViroPharma, a rare disease biopharmaceutical firm, for $4.2 billion (3.1 billion euros).

 

"Shire plc and ViroPharma Incorporated today announce that their boards of directors have unanimously approved, and the companies have entered into, a merger agreement pursuant to which Shire will acquire all the outstanding shares of the rare disease company ViroPharma for ... a total consideration of approximately $4.2 billion," the pair said in a statement.