AstraZeneca Canada Inc. v. Apotex Inc., 2014 FC 638

Drug: esomeprazole 

Apotex was successful in the previous NOC Proceeding. It came to market with an esomeprazole product. AstraZeneca sued for patent infringement and Apotex counterclaimed with allegations of invalidity. The Court held that the patent at issue was invalid.

The Court initially considered Apotex’ allegation that AstraZeneca Canada lacked standing. However, this allegation was dismissed as lacking credibility. The Court then considered issue estoppel, as raised by Apotex, with respect to the validity of the patent. The Court held that the doctrine of issue estoppel did not apply as the evidentiary record was not shown to be sufficiently similar. The Court then considered Apotex’ allegations of abuse of process; holding that shifting arguments as to the promise is not abusive, but shifting factual positions is more problematic. However, in the end, the Court accepted AstraZeneca’s new factual position regarding a limited motivation to investigate enantiomers at the time. The Court then considered the grounds of invalidity alleged by Apotex.

In considering the allegation of inutility, the Court held that one must consider the patent as a whole, from the perspective of a skilled person in relation to the science and information available at the time of filing. The Court held that the promise, if there is an explicit promise, must be related to how the patent will ultimately be used. Thus, “stability against racemization” was held not to be a promise in and of itself; but, rather, an integral aspect of the utility of the drug as a pharmaceutical in therapy.

In the patent, the statement at issue, in relation to the promise, was: “It is desirable to obtain compounds with improved pharmacokinetic and metabolic properties which will give an improved therapeutic profile such as a lower degree of interindividual variation. The present invention provides such compounds…” (para 113). The Court held that the word “will” in this phrase made it a promise. The Court held that the limited data AstraZeneca had on three human livers and six plasma re-analyses could not form the basis for a sound prediction of utility with respect to an improved therapeutic profile, across an entire patient population. Similarly, the Court held that AstraZeneca did not have the factual basis to predict that the enantiomer would have improved pharmacokinetic and metabolic properties, as promised by the patent. Thus the patent was invalid for inutility.

In considering the question of proper disclosure, the Court held that the Supreme Court’s decision in AZT, when combined with its obiter remarks in Teva sildenafil overturn previous FCA cases. Thus, “proper disclosure” of utility only applies to new use patents, if it applies at all.

The Court also considered the allegations with respect to lack of novelty and obviousness, but dismissed them both. In considering obviousness, the Court merged its analysis regarding obviousness and obvious to try, holding that the obvious to try inquiry occasionally supplements the fourth step of the general obviousness test, and this was one of those situations.