Bristol-Myers Squibb Canada Co. v. Teva Canada Limited, 2017 FCA 76 Drug: atazanavir
The Court of Appeal dismissed Bristol-Myers Squibb's appeal from the Trial Judge's decision refusing its application for a writ of prohibition on the basis that Teva's allegation of invalidity for obviousness was justified. The underlying proceeding related to two patents and an order of prohibition was granted in respect of the ‘840 Patent, but not the ‘736 Patent (see 2016 FC 580, our summary here). This appeal concerned only the '736 Patent, which covered a salt of atazanavir.
The Trial Judge had found that the allegation of obviousness was justified since it was more or less self-evident to a person skilled in the art that improving the solubility of atazanavir ought to improve its bioavailability. On appeal, Bristol-Myers Squibb argued that the Trial Judge had failed to properly apply the “obvious to try” test as set out by the Supreme Court in Apotex Inc. v. Sanofi-Synthelabo Canada Inc., 2008 SCC 61 ("Plavix").
The Court of Appeal came to the same conclusion as the Trial Judge but for different reasons. After a thorough review of Plavix as it related to obviousness, the Court of Appeal found that Bristol-Myers Squibb's categorical approach to obviousness was inappropriate. Bristol-Myers Squibb had submitted that obviousness cannot be shown unless all the elements of the inventive concept can be predicted with a high degree of certainty. The Court of Appeal disagreed, noting that not every case requires recourse to the “obvious to try” test and not every recourse to the “obvious to try” test must follow in the furrow of the preceding application of that test.
With respect to the Trial Judge's findings, the Court found that she had erred in the identification of the inventive concept, which focused on the properties of atazanavir bisulfate. The Court of Appeal found that the inventive concept in this case was atazanavir bisulfate, a salt of atazanavir which is pharmaceutically acceptable because it has equal or better bioavailability than the atazanavir free base. Having correctly identified the inventive concept, the Court of Appeal concluded that there was no difference between the prior art and the inventive concept or the solution taught by the patent. Therefore, Teva's allegation of obviousness was justified according to step 3 of the obviousness framework, and it was not necessary to apply the "obvious to try" test. The Court of Appeal noted that Teva's allegation that the '736 Patent was obvious would have still been justified under the "obvious to try" test.