Pfizer Canada Inc. v. Mylan Pharmaceuticals ULC – 2014 FC 38

In this case Pfizer brought a prohibition application under the PM(NOC) Regulations to prevent the Minister of Health from issuing a NOC for Mylan’s generic version of the anti-inflammatory drug Celecoxib, sold by Pfizer under the brand name Celebrex. Mylan had alleged that Pfizer’s Canadian Patent No. 2,177,576 (‘576) covering Celebrex is invalid for inutility. The main issue was whether the ‘576 patent promised that Celebrex would be useful in significantly reducing harmful side effects in humans, as compared to other Non-Steroidal Anti-Inflammatory Drugs (NSAIDs).

The Court found that the ‘576 patent did not promise reduced side effects in humans [60], and therefore did not lack utility.

The Court examined the wording of the ‘576 patent, which includes “[t]he compounds are useful as anti-inflammatory agents, such as for the treatment of arthritis, with the additional benefit of having significantly less harmful side effects.” [30] The following paragraph of the specification includes the statement that the invention preferably includes compounds which selectively inhibit COX-2 over COX-1: “[s]uch preferred selectivity may indicate an ability to reduce the incidents of common NSAID-induced side effects.” [Court’s emphasis] [32]

The Court heard and considered expert testimony from both Pfizer and Mylan on the construction of the promise. The Court then focused on the use of the word “may” and stated that “[t]he word ‘may’ connotes a possibility; maybe yes, maybe no. While it was hoped the selectivity would reduce side effects, no such claim was made.” [65]

The Court rejected the approach of Mylan’s expert who used a problem-solution approach to argue that the point of ‘576’s invention must be reduced side effects, because otherwise Celebrex would have been one among many similar known compounds. [66]

The Court also quoted favorably an earlier decision of Zinn J. for the proposition that “a utility not expressed in the claim portion of the specification ‘[…] should be presumed to be a mere statement of advantage unless the inventor clearly and unequivocally states that it is part of the promised utility’.” [70] In addition, the Court rejected Mylan’s argument that the Federal Court of Appeal decision in Eurocopter (2013 FCA 219) stands for the proposition that “a promise need not be explicit and need not be set out in the claims portion of the specification.” [71]

Mylan also pointed out that in an earlier proceeding under the PM(NOC) Regulations, 2007 FC 81, the Federal Court had construed the utility of the ‘576 patent to include “the duality of treatment of inflammation and reduction of unwanted side effects such as ulcers of the gastrointestinal system”. [13]

The Court rejected this argument on the basis that the earlier determination was largely on the basis of a concession by Pfizer, and that this concession during an earlier NOC proceeding was not binding on Pfizer during the instant NOC proceeding. [78] Furthermore, Mylan’s argument was undermined by the factual findings of demonstrated utility in the earlier decision. [75-76]

Commentary

In this decision the Court has taken a more restrained approach to construing the promise of a patent. The Court cited with approval the recent Plavex decision from the Federal Court of Appeal (2013 FCA 186) and underlined the distinction between the potential use of an invention and an explicit promise to achieve a specific result. [68] This may hint at a trend towards a less expansive and more judicious approach to promise of the patent.