Seven months after making an initial offer, Italy’s Chiesi Farmaceutici has agreed to acquire the rest of Cornerstone Therapeutics it does not already own to expand its presence in the USA.

Chiesi currently owns 58% of Cornerstone and is paying $9.50 a share in cash, or about $255 milion, for the rest. This represents a 78% premium to the latter’s closing price on February 15, the last trading day prior to Chiesi's initial written proposal, and a premium of 42% to the high end of the range of its first offer, which would have been worth about $177 million.

The purchase gives the Parma-headquartered company “a foundation for new projects in special care and respiratory disorders and will provide a sales channel on all products Chiesi intends to commercialise in the USA”. The firm added that it will become "a bigger player in special care in the USA”.

Chief executive Ugo Di Francesco added that “we will continue to promote Cornerstone's market-leading respiratory products, as we establish a strong footprint in the special care market”.