By Allison Grande

Law360, New York (October 27, 2010, 3:54 PM ET) -- AstraZeneca UK Ltd. has launched a patent infringement suit against Watson Pharmaceuticals Inc. in its most recent attempt to block generic-drug makers from producing copycat versions of its blockbuster cholesterol drug Crestor.

AstraZeneca's complaint, lodged Tuesday in the U.S. District Court for the District of Delaware, claims that Watson's new drug application for approval to market rosuvastatin zinc tablets infringes U.S. Patent Number RE37,314.

While AstraZeneca claims that Watson's NDA “relies upon safety and efficacy investigations of plaintiff's Crestor tablets,” the defendant contends in a press...