Pfizer announced that the Court of Appeals for the Federal Circuit (CAFC) has upheld the two main US patents covering Celebrex (Celecoxcib), the company's Cox-1 enzyme selective non-steroidal anti-inflammatory (NSAID) drug. Generic manufacturer Teva Pharma challenged the Orange book listed patents. The panel ruled that the patents (US5466823 and US5563165) covering the active pharmaceutical ingredient (API) and a pharmaceutical composition thereof are valid, enforceable and infringed by the generic manufacturer's product. In the same decision, the court ruled that a third patent (US 5760068) covering the use in the treatment of inflammation was invalid. The decision prohibits Teva from launching a competitor drug in the US until May 2014. Either party may request a rehearing by the court of appeals or a review by the US Supreme Court.
35 U.S.C 121 blocks the use of a parent application “as a reference … against a divisional application” if the divisional was the result of a restriction requirement.
One of the Pfizer patents (the ‘068) is a continuation-in-part (CIP) filed after a restriction requirement. On appeal, the CAFC confirmed that Section 121 does not apply to CIPs: “a divisional application contains an identical disclosure to its parent application, but a CIP introduces new matter. . . . [T] he protection afforded by section 121 . . . is limited to divisional applications.”
Thus, the parent application of a CIP will potentially be used for an obviousness-type double patenting rejection. Here, the CAFC held that the CIP claims were indeed obvious when compared to the parent application.
A patent is invalid when the applicant fails to satisfy the best mode requirement of Section 112. The requirement can be broken down into two elements:
Whether the applicant subjectively “possessed” a best mode for practicing the invention at the time the application was filed; and, if so, Whether the disclosure would objectively enable a PHOSITA to practise the best mode. Like other invalidity issues, best mode is determined on a claim-by-claim basis. There was no real question here that the COX-specific claims did satisfy the best mode requirement. The appellate panel refused to speculate further on the moot issue of how the best mode requirement is met for claims covering a larger class of compounds. (As reported earlier by patently-O)
Celecoxib was developed by G. D. Searle & Company and co-promoted by Monsanto (parent company of Searle) and Pfizer under the brand name Celebrex. Monsanto merged with Pharmacia, from which the Medical Research Division was acquired by Pfizer, giving Pfizer ownership of Celebrex. The drug was at the core of a major patent dispute that was resolved in Searle's favor (later Pfizer) in 2004. In University of Rochester v. G.D. Searle & Co., 358 F.3d 916 (Fed. Cir. 2004), the University of Rochester claimed that United States Pat. No. 6,048,850 (which claimed a method of inhibiting COX-2 in humans using a compound, without actually disclosing what that compound might be) covered drugs such as celecoxib. The court ruled in favor of Searle, holding in essence that the University had claimed a method requiring, yet provided no written description of, a compound that could inhibit COX-2 and therefore the patent was invalid.After the withdrawal of rofecoxib (Vioxx) from the market in September 2004, Celebrex enjoyed a robust increase in sales. However, the results of the APC trial in December of that year raised concerns that Celebrex might carry risks similar to those of Vioxx, and Pfizer announced a moratorium on direct-to-consumer advertising of Celebrex soon afterwards. After a significant drop, sales of Celebrex have recovered, and reached $2 billion in 2006. Pfizer resumed advertising Celebrex in magazines in 2006Celebrex was approved by the FDA in 1998. Its sales totaled $1.7 billion the US in 2007.
Orange book blog ( Link) and Patentdoc (link) have come up with interesting review on Celebrex litigation
