For the second time in a month, a complaint of infringement of patent has been filed against Zydus Pharmaceuticals (USA), a wholly-owned subsidiary of Ahmedabad-based pharma major Cadila Health-care (Zydus Cadila) at a US district court.
Pfizer has filed a lawsuit against Zydus’ abbreviated new drug application (ANDA) that seeks the approval to market a generic version of Pfizer’s pharmaceutical product Pristiq (an anti-depressant drug), before the expiration of the US patent. Earlier this month, Arizona-based Medicis Pharmaceutical Corporation had filed a similar complaint against Zydus Cadila’s US arm. The complaint related to a drug used for the treatment of acne.
In its complaint, Pfizer said the company and its wholly-owned indirect subsidiary Wyeth Pharmaceuticals held the approved new drug application (NDA) for O-desmethylvenlafaxine succinate-extended release tablets of 50 and 100 mg dosages. These are sold by Pfizer under the trade name Pristiq.
Zydus has been accused of seeking permission of the US FDA to commercially manufacture, use, sell, or import its generic product before Pfizer’s patent had expired. Pfizer added the Zydus ANDA referred to and relied upon the Pristiq NDA, and contained data which, according to Zydus, demonstrated the bioequivalence of Zydus products and Pristiq. Zydus Cadila Chairman and Managing Director Pankaj Patel said, “It is a routine thing that happens with almost every ANDA filing in the US. The company is taking appropriate action.”
Pfizer claimed it had received a letter from Zydus in May, stating Zydus had included a certification in the ANDA that Pfizer’s patent for Pristiq was invalid, or would not be infringed upon by the commercial use or sale of the Zydus product. In its complaint, Pfizer told a New Jersey district court if Zydus USA was not restricted from infringing on its patents, it would cause “irreparable harm” to the company. It also sought a directive from the court for an injunction, restricting Zydus USA from infringing on its patents, and the manufacture, use, sale, or distribution of any current or future version of the product described in its ANDA, before the expiration of the patent.
Pfizer has also filed a suit against Watson Laboratories of Florida, a subsidiary of specialty pharmaceuticals company Watson Pharmaceuticals, in the US district court of Delaware, seeking to prevent Watson from commercialising its desvenlafaxine product before the expiration of US patent number 6,673,838. Watson had filed an ANDA, seeking to manufacture and sell a generic version of Pfizer’s Pristiq.
For the year ended April 30, Pristiq recorded sales of about $559 million in the US.