AstraZeneca Canada Inc. v. Teva Canada Limited.

AstraZeneca Canada Inc. v. Teva Canada Limited.

Drug: SEROQUEL XR® quetiapine fumarae

Teva sent two Notices of Allegation, one in respect of 50mg tablets and the second in respect of 150, 200, 300 and 400mg tablets, which were addressed in separate proceedings. The Court indicated that the construction of the claims is not contested. The Court then held that “[w]here, as in this case, the inventive concept of the claims is not discernible from the claims themselves because they present a bare chemical formula, the Court is directed to read the specification in the patent to determine the inventive concept of the claims”. After a purposive and complete reading of the patent, the Court concluded that decreased occurrence of dose dumping and less frequent dosing regimen are key elements of the inventive concept.

The Court reviewed the properties of quetiapine that were known in the prior art, as well as other general knowledge. The Court held that the inventive concept of the invention is “a sustained release formulation of quetiapine hemifumarate, made with HPMC as the gelling agent and one or more excipients, with a view to decreasing the occurrence of dose dumping and to enabling a less frequent dosing regimen.”

The Court accepted Teva’s interpretation of the “obvious to try” portion of the test for obviousness as more or less self-evident “to conduct routine experimentation with a fair expectation of success.” The Court then considered a number of factors such as the extent, nature and effort required to achieve the invention, motivation and actual course of conduct. The Court drew “an adverse inference from AstraZeneca’s failure to provide evidence” with respect to the length or difficulty of the work conducted by the inventors, or whether the inventors had a better knowledge base than the skilled person. Accordingly, the Court found that it was more or less self-evident to try to obtain a sustained release formulation of quetiapine and that the skilled person would have had a fair expectation of success.

The Court held that it was not necessary to consider the allegation of ambiguity. Costs were awarded in the middle of Column IV.