Intellectual property lawyers foresee critical repercussions in local patent laws and the pharmaceutical and life sciences spaces with a recent Supreme Court of Canada ruling which rejected “promise doctrine” in a patent dispute involving two large Canadian pharmaceutical companies.
The SCC’s unanimous ruling stems from the AstraZeneca Canada Inc. vs. Apotex Inc. case which pitted the two firms against each in a dispute concerning the compound esomeprazole Nexium. The compound is AstraZeneca’s proton pump inhibitor (PPI) drug for reducing gastric acid. It is used to treat conditions such as reflux esophagitis.
A trial judge had earlier relied on the promise doctrine in invalidating AstraZeneca’s patent and ruling in favour of a challenge by generic drug maker Apotex. However, last week, the SCC rejected the promise doctrine and validated AstraZeneca’s patent.
“The Supreme Court’s total rejection of the promise doctrine is clear: ‘The Promise Doctrine is not the correct method of determining whether the utility requirement under s. 2 of the Patent Act is met’; ‘it is not good law’ and is‘unsound,” said lawyer Lynn Ing.
Ing is a member of the Smart & Biggar team which successfully represented AstraZeneca before the SCC. Other members of team were Guman Gaikis, and Yoon Kan.
The SCC ruling goes beyond merely validating AstraZeneca’s ruling, according to Julie Desrosier, lead lawyer of Fasken Martineau’s global technology and intellectual property group. Desrosier, together with Kang Lee, also of Fasken, represented the International Federation of Intellectual property Attorneys (FICPI) which were intervenors in the case.
“The Supreme Court’s decision in AstraZeneca has effectively hit the ‘reset’ button on the utility requirement, wiping out a decade’s worth of Federal Court patent jurisprudence, and returning the utility requirement to a low bar,” Desrosier said in an analysis of the case. “We expect that in the future, there will be very few utility arguments made by defendants in Canada, and even fewer of those arguments will be successful.”
She said validity disputes will now likely “return to the classic issues of novelty and obviousness.”
All patented inventions are required to be “useful” under the Canadian Patent Act. However, the act does not state exactly how courts should define usefulness. This resulted in the emergence of the “promise of patent” and “enhanced disclosure requirement,” in the mid-2000s. Also called the “promise doctrine,” it became the yardstick by which utility is measured.
This led to a contentious situation in which few patents were invalidated on basis of utility, according to an analysis written Desrosier, and Fasken associate lawyer, Michael Shortt.
Under the promise doctrine, usefulness was assessed by asking whether the patented invention was demonstrated or soundly predicted, at the Canadian filing date. This meant that the invention is supposed to do all the things which the patent specs promised. If the inventions fails to deliver on even one of those promised results, this would invalidate the promise.
Under the enhanced disclosure requirement, patentees are required to disclose additional information in the patent specification. For instance, if the patentee has access to studies which can provided reasonable scientific evidence that the invention is useful, this information must be contained in the patent document. If the patentee fails to include the information, the patentee cannot use them to prove utility.
Here’s how it all began.
The legal battle between AstraZeneca and Apotex started after Astra filed a patent related to esomeprazole Nexium.
Apotex sought approval from the federal minister of health to sell a generic version of the drug.
AstraZeneca was not able to stop the minister from providing Apotex a notice of compliance to sell the generic version.
AstraZeneca went after Apotex for patent infringement. Apotex, in turn tried to get AstraZeneca’s patent impeached.
The Federal Court, applied the promise of patent, in effect said the drug promised more than it can deliver. It sided with Apotex and said the patent was invalid. The Federal Court of Appeal upheld this finding.
However, the SCC rejected the promise doctrine as the proper yardstick to measure the utility of AstraZeneca’s patent.
Justice Rowe, who wrote the unanimous SCC ruling, said the promise doctrine had three major failings:
- The doctrine inappropriately referenced the disclosure portion of the patent when assessing validity of even unambiguous claims. Rowe believes that claims have to be the primary focus of an assessment of validity.
- Holding patentees to promises made disclosure “inappropriately conflated the utility requirement of section 3 with the sufficient disclosure requirement of section 27(3).”
- Requiring an invention to fulfill every promise “meant that inventions of undisputed usefulness…were denied patent protection because they did not fulfill other, potentially secondary, promises of usefulness.”
The ruling has left a few questions unanswered such as:
- How does one determine the “subject matter of the invention?”
- Is this the same thing as the “inventive concept” referred to by the SCC?
- What is the status of enhanced disclosure requirement?
The SCC’s decision may have “substantially simplified and clarified the applicable legal tests,” said Desrosier in her analysis. “But some questions remain to be worked out.”