The Supreme Court of Canada heard oral arguments on November 8, 2016 in an important appeal challenging the "promise of the patent" utility doctrine in Canada. In AstraZeneca Canada Inc. v. Apotex Inc. (Esomeprazole), Court File No. 36654, the Supreme Court is asked to decide on the question of whether the doctrine properly exists.

At issue is Canadian Patent No. 2,139,653 pertaining to esomeprazole, a compound which is used in reducing gastric acid. As of the filing date, the patentee had performed internal studies, but the drug had not yet been clinically proven in humans. The drug received market approval and became commercially successful. Nevertheless, in an action for impeachment, the Federal Court held the '653 patent to be invalid on the basis that the patentee had not demonstrated or soundly predicted an improved therapy in patients at the filing date, which it found was promised in a statement on page 1 of the patent (2014 FC 638). The Federal Court of Appeal affirmed the holding (2015 FCA 158).

In the appeal to the Supreme Court, seven organizations were granted leave to intervene, namely the Intellectual Property Institute of Canada, the Intellectual Property Owners Association, the Fédération internationale des conseils en propriété intellectuelle, Innovative Medicines Canada and BIOTECanada (jointly), the Centre for Intellectual Property Policy, and the Canadian Generic Pharmaceutical Association.

The oral arguments started out with counsel for AstraZeneca discussing claim construction. In Canada, claims are construed purposively to determine the meaning of words in a claim and identify essential elements of the claim. Justice Abella asked how utility was measured. Counsel for AstraZeneca explained that if a claim recites a specific use, and the use is found to be an essential element, then that use must be delivered. If a use is not recited in a claim, then it is not an essential element and the claim merely needs to have some utility. Exemplary claims were claim 26 which recited use of omeprazole for gastric inhibition, and claim 8 which recited omeprazole.

Justice Brown asked when a court can look to the disclosure in construing the claims. Counsel for AstraZeneca answered that, while purposive construction focuses on the claims, it looks at the entire disclosure. Counsel for AstraZeneca later explained that focusing on the claims provides clarity to the public, apparently in reference to the notice function of claims.

Counsel for Apotex argued that the appeal should be limited to the issues that were argued in the courts below. Chief Justice McLachlin disagreed, indicating that where there is divergence in the law, the Supreme Court is free to clarify the law.

Next, counsel for Apotex argued that statements that AstraZeneca made in the patent about the problem that the invention solves cannot be ignored. Chief Justice McLachlin asked, "So if that statement is, let's say, a bit extravagant, but the patent is nonetheless very useful – it cures the disease or provides relief – that extravagant statement will mean that this useful, novel, and in other respects totally compliant with the Patent Act patent fails, because of that one overstatement ... isn't that the logical conclusion of what you are putting forward?" Counsel for Apotex answered that it depends on the patent, and it could happen. Justice Karakatsanis echoed her question, asking about whether any invalid claims should not be severed from the valid claims. Counsel for Apotex answered the claims should not be severed in this matter. He argued that, while the claims define the monopoly of the invention, it is the description that defines the invention. In his view, the invention as disclosed in this matter included a promise that had to be met for the '653 patent to be valid.

Overall, the Supreme Court appeared to be concerned that the promise doctrine was unworkable and severe. The Supreme Court reserved its decision. A decision from the Supreme Court in patent matters usually issues within 6 months. In the meantime, Applicants may consider reviewing the disclosure of their applications for any statements that may be interpreted as a promise of utility, with a view to possible amendment to soften such statements.

Jean-Charles Grégoire is a lawyer and registered Canadian patent agent at Marks & Clerk Canada. His practice focuses on securing patent and industrial design protection.

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