Shire shares fall 13% as rival drug gets US approval
Shares in pharmaceutical company Shire fell almost 13% after US regulators approved a rival's cut-price version of its drug Adderall XR.
The US Food and Drug Administration had approved Actavis Group's generic version of Shire's hyperactivity disorder drug on Saturday.
Despite the news, Shire said it would deliver good full-year earnings growth.
Shire's shares fell 12.7% in early trading, making it the biggest faller on the FTSE 100.
Adderall XR is Shire's second-biggest selling drug. Until now, Shire has been the sole producer of the two forms of Adderall XR, and analysts said the arrival of a new competitor would increase pricing pressure.
Deutsche Bank cut its 2012-2013 earnings forecast by 5-6% to reflect the new competition, but said it still expected double-digit growth from the drugmaker.
Shire said that it would remain competitive in the Adderall XR marketplace, and "continues to believe that it will deliver good, full year 2012 earnings growth".