Pfizer Accuses Aurobindo of Infringing on Rheumatoid Arthritis Drug Patents

Yesterday, Pfizer Inc., C.P. Pharmaceuticals International C.V., PF PRISM C.V., PBG Puerto Rico LLC, and PF PRISM IMB B.V. (collectively, Pfizer) filed suit against Aurobindo Pharma Ltd. and Aurobindo Pharma USA Inc. (collectively, Aurobindo) in the District of Delaware. The patent infringement complaint contends that the filing of Aurobindo’s Abbreviated New Drug Application (ANDA) seeking U.S. Food and Drug Administration (FDA) approval to sell generic copies of two different dosages of Pfizer’s Xeljanz tablets is illegal.

The filing explains that the active ingredient in Xeljanz is tofacitinib citrate. The drug is used to treat adults with certain forms of rheumatoid arthritis, psoriatic arthritis, and ulcerative colitis and children 2 years and older with certain manifestations of juvenile idiopathic arthritis. Pfizer’s two patents-in-suit reportedly cover claims relating to Xeljanz’s formulation.

The complaint states that Pfizer’s patents are listed in the FDA’s Orange Book, the colloquial name for its publication, titled “Approved Drug Products with Therapeutic Equivalence Evaluations.” One of the patents expires in March 2023, the other in December 2025.

Last November, Aurobindo reportedly notified Pfizer of its intent to seek approval to market and sell generic versions of Xeljanz prior to the patents’ expiration. The complaint states that the notice letter included a “Paragraph IV” certification contending that Pfizer’s two patents are invalid, unenforceable, and/or will not be infringed by Aurobindo’s commercial manufacture of generic versions.

Aurobindo’s letter also included an attachment detailing the factual and legal basis for its Paragraph IV certification. Pfizer explained that Aurobindo argued that the two patents are invalid but did not argue that its generic versions would not infringe upon them. On the contrary, Pfizer argued that approval of Aurobindo’s ANDA and bringing the generic products to market would infringe directly and by inducement. It sought declaratory and injunctive relief and its attorneys’ fees and costs.

The lawsuit is the second Aurobindo has faced in the last 30 days. In December, Aurobindo was sued for infringement by Merz Pharmaceuticals LLC and Merz North America Inc. after it filed an ANDA to make, market, and sell generic versions of Merz’s Cuvposa, a drug that treats sialorrhea, a condition that causes drooling or excessive salivation. 

Pfizer is represented by Morris, Nichols, Arsht & Tunnell LLP and of counsel Arnold & Porter Kaye Scholer LLP and DLA Piper LLP.