AstraZeneca said it will appeal the ruling. Both patents are due to expire in September 2007.
The drug, in addition to treating hypertension, is also used for the long-term treatment of angina pectoris and certain types of heart failure. Andrx believes it may be entitled to 180 days of market exclusivity on the 50 mg strength of generic Toprol-XL. The drug had total U.S. sales of $1.29 billion last year, AstraZeneca said.Shares of Andrx were rising 4.9% to $17.40 in premarket trading. AstraZeneca's American depositary shares were losing 3.8% to $47.48.