King, Astellas File Suit Against Teva Over Adenoscan Patent

King Pharmaceuticals and Astellas Pharma have jointly filed a lawsuit against Teva Pharmaceutical accusing the generic drugmaker of violating King's patent on Adenoscan.

Filed in the U.S. District Court for the District of Delaware, the lawsuit seeks a court order prohibiting the FDA's approval of Teva subsidiary Sicor's abbreviated new drug application for a generic version of pharmacologic stress agent Adenoscan (adenosine injection) before the expiration of King's U.S. patent number '877 May 18, 2009, Astellas said.

Adenoscan is used as an adjunct to thallium-201 myocardial perfusion scintigraphy in patients unable to exercise adequately, Astellas said. Astellas shares certain rights under King's '877 patent and has marketed Adenoscan in the U.S. since 1995.