News briefs: US Crestor patent upheld; Pfizer animal health plans; Teva South Korea JV

Anglo-Swedish drug major AstraZeneca (LSE: AZ) said on Friday that the US Court of Appeals for the Federal Circuit has upheld the decision of the District Court, District of Delaware, finding that the US substance patent protecting the firm’s blockbuster cholesterol drug Crestor (rosuvastatin calcium) (RE37,314 – the ‘314 patent) is valid and enforceable.

The defendants may seek a rehearing and/or review by the US Supreme Court. Absent a reversal of this decision, none of the Abbreviated New Drug Applications filed by Apotex, Aurobindo, Cobalt, Glenmark, Mylan, Par, Sandoz, Sun, Teva and Torrent may be approved by the FDA prior to expiration of the ‘314 patent. The ‘314 patent, which expires in 2016, covers rosuvastatin calcium, the active ingredient in CRESTOR. The Federal Circuit also held that Apotex Corp. was liable as a submitter and is therefore bound by the District Court’s decision. Crestor, AstraZeneca’s biggest selling product, generated sales of $6.6 billion last year.

The generic drugmakers argued the Crestor patent was unenforceable because the original patent applicant, Shionogi Seiyaku Kabushiki Kaisha of Japan, withheld certain information from the US Patent and Trademark Office. AstraZeneca licensed the Crestor patent from Shionogi. Judge Jay Plager suggested the appeals court owed deference to the trial judge's finding that Shionogi's errors were not intended to deceive the Patent Office, but instead were likely the result of confusion and inexperience at Shionogi's patent department.