Pfizer Alleges Micro Labs Infringing on Xeljanz Patents


On Thursday in the District of Delaware, Pfizer Inc. and its subsidiaries filed a complaint against Micro Labs Ltd. and its subsidiary, alleging infringement of its patents for drug Xeljanz.

Pfizer holds the new drug application (NDA) for 10 mg tofacitinib citrate tablets, under the brand name Xeljanz, used to treat adults with ulcerative colitis, the complaint said. The patents-in-suit corresponding to Xeljanz are U.S. Patents Nos. RE41,783 and 6,965,027, which are set to expire Dec. 8, 2025, and March 25, 2023, respectively, according to the Food and Drug Administration’s (FDA) patent publication, the Orange Book.

According to the complaint, Micro Labs sent a letter Feb. 1 to notify Pfizer that it had submitted an abbreviated new drug application (ANDA) seeking FDA approval to market and sell 10 mg tofacitinib citrate tablets. The defendant claimed in the letter that its generic product would not infringe on the patents-in-suit, arguing that all claims of the patents are invalid; Pfizer contended otherwise.

Pfizer argued that Micro Labs’ manufacturing, marketing, and selling of its ANDA product before the expiration of Pfizer’s patents-in-suit constitutes infringement. According to the complaint, Micro Labs knew its conduct was infringement, given the patents’ listings in the Orange Book.

The plaintiff claimed that if Micro Labs is not enjoined from continuing its actions, it will sell and distribute its generic product in the U.S., which will “substantially and irreparably” harm the plaintiff.

Pfizer is seeking a judgment that Micro Labs’ ANDA product infringes on the patents-in-suit unless it only is manufactured and sold after the patents’ expirations, enjoinment of Micro Labs and affiliates from manufacturing, selling, and distributing its ANDA product before the patents-in-suit expire, and monetary damages, among other relief.

Pfizer is represented by Morris, Nichols, Arsht & Tunnell LLP.