Case: Alcon Canada Inc. v. Canada (Health), 2014 FC 149

Drugs: Pataday (0.2% concentration of olopatadine)

Nature of case: Prohibition proceeding under the Patented Medicines (Notice of Compliance) Regulations

Date of decision: February 14, 2014


This case concerns a proposed generic version of the brand name drug PATADAY, an eye drop solution used to treat allergic and inflammatory eye reactions. The active pharmaceutical ingredient is a 0.2% concentration of olopatadine. Alcon Canada Inc. and Alcon Pharmaceuticals Ltd. (Alcon) sought an order prohibiting the Minister of Health from issuing a notice of compliance to Cobalt Pharmaceuticals Company (Cobalt) in respect of the proposed generic product.

Canadian Patents No. 2,195,094 (the ‘094 Patent), 2,447,924 (the ‘924 Patent) and 1,337,603 (the ‘603 Patent) were listed against PATADAY on the Patent Register. The ‘603 Patent expired on November 21, 2012 and its validity was not contested by Cobalt in its Notice of Allegation. The ‘094 Patent had been held to be “invalid” in a previous PMNOC application between Alcon and Apotex in respect of PATANOL, an eye drop solution with a 0.1% concentration of olopatadine (Alcon Canada Inc v Apotex Inc, 2012 FC 410). Alcon relied solely on the ‘924 Patent in the present case.

Cobalt alleged that the ‘924 Patent was invalid on the basis of obviousness, lack of utility and sound prediction, overbreadth of claims, ambiguity and insufficiency. Infringement was not at issue. Gleason J. of the Federal Court found merit in Cobalt’s allegations of lack of utility, sound prediction and overbreadth. Therefore, Alcon’s application was dismissed.

The issues

Promise of the ‘924 Patent

Gleason J. began her analysis by construing the two claims of the ‘924 Patent that were at issue. She found that these claims covered particular combinations of olopatadine and polyvinylpyrrolidone (PVP) having an average molecular weight of 5K to 1600K “in an amount sufficient” to improve the physical stability of the solution, and excluding five named excipients. The inventive concept and promised utility of the ‘924 Patent was held to be that PVP at sufficient concentrations enhanced the physical stability of higher concentration (0.2% to 0.6%) of olopatadine solutions in most instances, whereas the five excluded excipients did not.


Cobalt asserted that the stability-enhancing properties of PVP were disclosed in the ‘094 Patent and in several other pieces of prior art. Gleason J. rejected Cobalt’s argument. The prior art did not disclose that PVP could perform its stability-enhancing function in an olopatadine solution, or that the five excluded excipients could not do so nor would this have been obvious to a person skilled in the art. Gleason J. also found that addition of appropriate amounts of PVP to the solutions of Claims 2 and 7 was not “obvious to try” as (1) it was not more or less self-evident to use PVP in preference to the five excluded excipients; (2) several rounds of experiments were conducted before the PATADAY formula was perfected (although Gleason J. found it “troubling” that the inventors were apparently not involved in determining what experiments would be reported in the ‘924 Patent); and (3) the prior art did not disclose any motive for discovering the invention claimed in the ‘924 Patent, even though there was a business motive for Alcon to produce a 0.2% olopatadine solution as a competitor had just started selling a competing once-a-day solution.

Utility and sound prediction

Gleason J. held that the utility of PVP to achieve the promised stability enhancement of olopatadine solutions had not been demonstrated for all molecular weights disclosed in the ‘924 Patent as of the filing date. Gleason J. added that while it may not be necessary to test every single available grade of PVP to demonstrate utility, Alcon should have tendered evidence regarding how many points along the “molecular weight range of 5K to 1600K need be tested in order to satisfy the demonstration of utility across the whole range”. In the absence of such evidence, she found that data for only the 58K and 1300K molecular weights of PVP was insufficient to demonstrate utility across the entire range of 5K to 1600K.

In regard to sound prediction, Gleason J. found that the utility of PVP to achieve the promised stability enhancement was not soundly predicted for all molecular weights given that the ‘924 Patent failed to disclose a factual basis or sound line of reasoning to support that prediction.

Claims overbroad

Gleason J. held that Cobalt’s allegation of overbreadth was simply another way of articulating the utility argument Therefore, for the reasons stated in the previous utility and sound prediction analysis, Gleason J. found that Claims 2 and 7 were overbroad as they contained promises that were broader than what could be demonstrated or soundly predicted to be useful.

Ambiguity and insufficiency

Gleason J. held that the term “in an amount sufficient” was not ambiguous, as the specification clearly set out the preferred amount of PVP to be added to the solutions. She also noted that “this type of description for the amount of a particular compound to be added to a pharmaceutical composition appears to be frequently used in pharmaceutical patents”. Cobalt’s insufficiency argument also failed, as Gleason J. found that what constituted the invention was the use of PVP to enhance the physical stability of oloptadine solutions, not the specific amount of PVP. Expert evidence established that fine-tuning of the amount of PVP to be used within the range provided in the specifications was a matter of routine experimentation, not an inventive step in itself even if it required some experimental work by persons of experience and skill.

Link to decision