(Reuters) - French drugmaker Ipsen SA (>> Ipsen) said on Monday it would buy some assets of U.S. peer Merrimack Pharmaceuticals Inc (>> Merrimack Pharmaceuticals Inc), including its pancreatic cancer treatment Onivyde, for about $1 billion.

Ipsen will pay $575 million cash at the closing of the deal and up to $450 million more, contingent on some approvals for Onivyde in the United States.

Reuters reported the deal on Sunday, citing people familiar with the matter.

(Reporting by Ismail Shakil in Bengaluru; Editing by Peter Cooney)

Stocks treated in this article : Ipsen, Merrimack Pharmaceuticals Inc