A Delaware District Court ruled that Pfizer can exclusively sell Lipitor until 2011 after finding that Ranbaxy Laboratories Ltd.’s generic version of Lipitor infringes on two Pfizer patents. Ranbaxy failed to prove Pfizer’s patents were invalid or unenforceable so Pfizer’s patents will remain in force until 2010 and 2011.
Pfizer owns U.S. Patent Nos. 4,681,893 (‘893 patent) and 5,273,995 (‘995 patent) which cover Lipitor. Ranbaxy notified Pfizer that it had filed an abbreviated new drug application seeking to sell a generic version of the drug, and a paragraph IV certification, asserting that its proposed generic product would not infringe either the ‘893 patent or the ‘995 patent. Shortly thereafter, Pfizer filed a patent infringement suit against Ranbaxy in the Delaware federal court.
Pfizer’s on a roll given that in October, a British court upheld the main patent covering atorvastatin in the United Kingdom through November 2011, though it did rule for Ranbaxy on a secondary patent challenge. Ranbaxy contends that Warner-Lambert (the original patentee) withheld material information from the Patent Office and misrepresented certain information when it failed to reveal an earlier filed application. In the Delaware court case, the judge wrote that “Pfizer has advanced reasonable and credible grounds for the non-production of certain data that weigh against a conclusion that … scientists and employees were intentionally deceiving the PTO.”
Ranbaxy was unable to show unenforceability due to inequitable conduct or invalidity of the patents based on claims of double patenting, obviousness and anticipation. However, Ranbaxy said it would appeal the ruling to the U.S. Court of Appeals for the Federal Circuit.
