Pfizer v. Mylan

Drug: donepezil

The Federal Court granted prohibition to Pfizer in respect of Mylan's Notice of Allegation (NOA) that the patent for the drug in question was invalid. The claims at issue related to the chemical compound and a therapeutic composition for treating senile dementia comprising the chemical compound. Mylan challenged the patent on grounds of utility, promise and a lack of sound prediction and these allegations were found to be not justified.

In its Memorandum of Fact and Law, Mylan also alleged that some of the testing and data as repeated in the patent was inaccurate. The Court found that the evidence as to what took place at Eisai was very difficult to follow, however, it need not be considered in the context of this proceeding as it was not an allegation made by Mylan in its NOA.

In considering utility, the Court held that the standard of utility is low in Canada. However, even given that standard, one must ask "useful for what"? The Court held that the concept of the promise of the patent comes into play in answering this question. In this case, the Court held that the utility of the compound was soundly predicted. Furthermore, the Court held that proof of a lack of toxicity at this stage is not a necessary requirement in order to demonstrate utility.