Pfizer Wins Caduet Patent Suit Against Ranbaxy

A federal judge has ruled in favor of Pfizer in a patent infringement suit involving Ranbaxy Laboratories and Pfizer’s patents covering Caduet.

Pfizer filed suit in March in the U.S. District Court for the District of Delaware alleging that a generic version of the drug proposed by Ranbaxy would infringe on two of its patents. Caduet combines the active ingredients in Pfizer’s cholesterol drug Lipitor (atorvastatin calcium) and its hypertension drug Norvasc (amlodipine besylate).

The ’893 patent covers atorvastatin calcium, and the ’574 patent covers the drug combination. The patents expire in 2010 and 2018, respectively. After Pfizer filed suit, Ranbaxy filed counterclaims seeking declaratory judgments that the ’893 patent is invalid and that the ’574 patent is invalid and not infringed.

The U.S. Circuit Court of Appeals for the Federal Circuit previously upheld the ’893 patent in Lipitor patent litigation. Pfizer argued that Ranbaxy’s counterclaim involving the obviousness of the ’893 patent is estopped by the company’s failure to raise this obviousness evidence in the Lipitor litigation, according to the judge’s Nov. 29 opinion. The court granted Pfizer’s motion to dismiss this counterclaim.

Ranbaxy could not be reached for comment by press time.