HAYWARD, Calif.--(BUSINESS WIRE)--IMPAX Laboratories, Inc. (OTC:IPXL) today announced that Pfizer Inc., Pharmacia & Upjohn Co. LLC, and Pfizer Health AB (collectively “Pfizer”) have filed a lawsuit against the Company in the United States District Court for the Southern District of New York alleging patent infringement related to IMPAX's filing of an Abbreviated New Drug Application (ANDA) for generic versions of Detrol LA® 2mg and 4mg capsules. IMPAX's ANDA submission includes a Paragraph IV certification stating the Company believes its product does not infringe Pfizer's listed patents or that the listed patents are invalid or unenforceable.
