Levocetirizine (Xyzal): Innovator sued Barr for Filing Para IV

Belgian drugmaker UCB SA and its U.S. partner, Sepracor Inc., have filed their fourth lawsuit against another generic player Barr Pharma in an effort to stave off a generic challenge to their antihistamine drug Xyzal (Levocetirizine). The lawsuit was filed in US district court for the Eastern District of North Carolina on July 30, 2008. UCB alleged that Barr pharma infringed the company's patent US5698558 (Expiry: September 24, 2012, which covers method of use of levocetrizine) for levocetirizine hydrochloride 5mg by filing an ANDA with USFDA. There is only one patent listed in orange book for this product.
US5698558 (Expiry: September 24, 2012)- This patent covers a method of treating the symptoms of seasonal and perennial allergic rhinitis in a human which comprises administering to a human in need of such symptomatic relief therapy an amount of (-) cetirizine, or a pharmaceutically acceptable salt thereof, substantially free of its (+) stereoisomer, said amount being sufficient to alleviate or palliate said allergic rhinitis.
The Company filed its ANDA containing a paragraph IV certification against ‘558 patent in January 2008. Xyzal (levocetirizine dihydrochloride) had annual sales of approximately $74 million in the U.S., based on IMS sales data for the twelve month period ending May 2008.
Earlier, innovator has filed lawsuit against Synthon (first para IV filer), Sun Pharmaceuticals, SandozHere and Here