In her February 14th decision of Alcon Canada Inc v. Cobalt Pharmaceuticals Company(2014 FC 149), Justice Gleason of the Federal Court denied Alcon’s application for an order of prohibition with respect to its PATADAY® product. PATADAY®, used to treat allergic and inflammatory eye reactions, contains a 0.2% solution of olopatadine. The validity of Canadian Patent 2,447,924 was at issue in this proceeding.

The ‘924 Patent

The relevant claims of the ‘924 Patent claimed pharmaceutical compositions for the treatment of allergic or inflammatory disorders of the eye and nose comprising olopatadine and the excipient PVP, where the composition does not contain any of five named “excluded excipients”. The two claims at issue in this proceeding (claims 2 and 7) both claimed allowable molecular weight ranges for PVP (5,000-1,600,000), and ranges of allowable olopatadine concentrations in the composition.

The Promise

The Court construed the promise of the patent before undertaking its utility analysis. The Court framed the promise as that “of the asserted claims”, and considered the promise of each of claims 2 and 7 separately (eventually finding separate promises for these two claims).

However, after making noted reference to the claims in determining certain elements of the promise, the Court went on to find that there is a promise that the excluded compounds would not enhance the physical stability of the claimed olopatadine solutions despite an absence of an explicit statement to this effect in the claims. Rather, the Court came to this aspect of the promise on the basis that the disclosure mentions that two of the five excluded excipients will not enhance the stability of the solution.  By way of inference, the Court found that this statement should apply to all five “excluded excipients”.

In construing the promise, the Court also considered the inventive concept of the claims. In particular, the Court held that the inventive concept included the fact that the excipient PVP enhances the solution’s stability and the excluded excipients do not.  The Court held that it was “incongruous” in the context of this patent to argue that the inventive concept was something different from the promise.

Promised Utility Not Met

The ‘924 Patent contained five examples relevant to the utility of claims 2 and 7. No data apart from these examples was considered for utility. From her review of these examples, the Court found that 58K molecular weight PVP enhanced stability of the solutions, and thus utility was demonstrated for this value. The other molecular weight tested, 1300K, had some positive information, but there also were experiments where utility was not shown. This information was held to be “not conclusive”, and thus insufficient to demonstrate utility.

With respect to sound prediction, the Court held that there was no basis for predicting that the entire range of molecular weights of PVP claimed will have a physically stabilizing effect. Based on a finding that the physical stability of solutions is random and unpredictable, the Court held that the need for disclosure of a sound line of reasoning was “heightened” in this case as compared to other sound prediction cases. Unusually, the Court did not mention the 58K data point in the sound prediction analysis, even though utility was found to be demonstrated for this value.

Allegations of obviousness, ambiguity, and sufficiency were dismissed. On the last point, the Court confirmed that trial and error experimentation is permissible in putting the invention into practice in order to satisfy the sufficiency requirement.


This decision once again highlights problems with the promise and utility doctrines in Canada. Unfortunately, the findings in this proceeding appear unlikely to see reconsideration via appeal, as Cobalt (under the new name Actavis Pharma Company) has already received its Notice of Compliance for its version of PATADAY®.

Click here for the Federal Court decision.