King Pharmaceuticals is to buy the rights to two of Elan Corp.'s drugs in the United States and Puerto Rico for $850 million.
The purchase includes insomnia treatment Sonata and muscle relaxant Skelaxin, rights to potential new formulations of these products, and Elan's primary care field sales force of more than 400 representatives.
In a press release, Bristol-based King said the acquisition of the Irish pharmaceutical company's unit will add to its earnings upon closing, and noted Sonata and Skelaxin had 2002 sales of about $238 million in the United States and Puerto Rico.
Under the agreement, King will reimburse Elan for the costs of developing new formulations of Sonata, and potentially pay Elan more than $70 million upon achievement of certain milestones, including regulatory approval.