Facts
Decision


On 17 October 2022, Justice St-Louis of the Federal Court granted a motion for summary trial brought by Teva, Pharmascience, Laboratoire Riva, Apotex and Mylan (the defendants) and dismissed the underlying actions of Lilly for infringement of Canadian Patent No. 2,226,784 (the 784 patent).(1)

Facts

The 784 patent was previously the subject of invalidity allegations in proceedings pursuant to the pre-amended Patented Medicines (Notice of Compliance) (PMNOC) Regulations whereby allegations of invalidity were dismissed as unjustified (for further details, see "Canadian Federal Court of Appeal clarifies test for double patenting" and "Federal Court of Appeal opines on the framework for analyzing obviousness-type double-patenting"). The defendants received their notices of compliance following expiry of the 784 patent on 11 July 2016. The underlying actions were based on manufacturing, importing and stockpiling prior to the 784 patent expiry, and included claims for springboard damages.

The issue raised in the present motion, which centred around the term "physiologically acceptable salt" was not specifically addressed in either of the two previous PMNOC decisions.

Decision

The Court held that each of the claims at issue (the asserted claims) were directed to a physiologically acceptable salt of tadalafil and/or 3-methyl tadalafil capable of being manufactured into a pharmaceutical composition with a pharmaceutically acceptable diluent or carrier, for the treatment of erectile dysfunction. For example, claim two provided:

2. A pharmaceutical composition for the curative or prophylactic treatment of erectile dysfunction in a male animal, comprising a compound selected from the group consisting of:

[tadalafil] or a physiologically acceptable salt or solvate thereof; and

[3-methyl tadalafil] or a physiologically acceptable salt or solvate thereof;

together with a pharmaceutically acceptable diluent or carrier.

The parties agreed that the ability to form a salt was the same as between tadalafil and 3-methyl tadalafil. Glaxo France had not made a salt of tadalafil prior to filing the application that led to the 784 patent. The defendants argued that the asserted claims were invalid for overbreadth, insufficiency and inutility.

The Court found that it was appropriate to proceed by way of a motion for summary trial.

The experts agreed that a salt of tadalafil could be made but did not agree as to whether such a salt would be "physiologically acceptable".

The Court held that the person having ordinary skill in the art (POSITA) would have understood that a "physiologically acceptable" salt required the salt to be non-toxic and to not cause harm but also accepted the defendants' submission that the POSITA would also have understood that the salt needed to be stable and pure, not degraded. The Court also held that the POSITA would have understood a "salt" to:

involve a transfer of proton. Salt consisted of a negatively charged species, called [an] anion that electronically interacts with a positively charged species, called a cation. In 1997, the POSITA would not have included cocrystals in the definition of salt.

The Court held that the defendants had met their burden and established that it was more probable than not that a physiologically acceptable salt of tadalafil could not be made. The asserted claims were therefore held to be invalid for overbreadth on the basis that the claims were broader than what was invented.

The asserted claims were also held to be invalid for insufficiency of disclosure on the basis that having only the specification, the POSITA could not produce the invention using only the instructions contained in the disclosure; the POSITA would need to complete a minor research project to try and find a physiologically acceptable salt of tadalafil.

Finally, while the Court held that the defendants had established that there was not enough common general knowledge to support a sound prediction of utility of a physiologically acceptable salt, in the absence of full argument, the Court declined to determine the legal question of whether such finding rendered the entire claim invalid for inutility.

Lilly has appealed.(2)

For further information on this topic please contact Andrea Berenbaum at Smart & Biggar by telephone (+1 416 593 5514) or email ([email protected]). The Smart & Biggar website can be accessed at www.smartbiggar.ca.

Endnotes

(1) Eli Lilly Canada Inc v Teva Canada Limited, 2022 FC 1398.

(2) A-244-22.