In a decision released today, the Supreme Court of Canada found Pfizer’s patent on sildenafil to be invalid for having an insufficient disclosure contrary to s.27(3) of the Patent Act.
The decision, Teva Canada Ltd. v. Pfizer Canada Inc., 2012 SCC 60, was an appeal from the Federal Court of Appeal in 2010 FCA 242 (A-292-09) which had upheld the decision of Justice Kelen in 2009 FC 638 (T-1566-07) granting a prohibition order under the Patented Medicine (Notice of Compliance) Regulations.
The focus on the Court’s analysis was on whether the patent adequately disclosed sildenafil and particularly whether claim 7 of Canadian Patent No. 2,163,446 (PDF) directed to sildenafil, the active ingredient in Viagra, could be analyzed apart from the other claims directed to other compounds, none of which had been shown to be effective[72]. The court wrote (at para 56):
Section 58 [of the Patent Act] simply states that valid claims survive in the face of one or more invalid claims. This section is engaged once it has been determined, on the basis of the patent as a whole, whether the requirements, including the disclosure requirements, have been complied with. Section 58 does not allow a court to consider the validity of a single claim — Claim 7 in this case — independently of the rest of the specification, even if the claim in question is the only one that may be valid. This section is engaged only after the validity analysis is carried out.
The court found that the specification as a whole did not inform a person skilled in the art to the invention[74]:
The disclosure in the specification would not have enabled the public “to make the same successful use of the invention as the inventor could at the time of his application”, because even if a skilled reader could have narrowed the effective compound down to the ones in Claim 6 and Claim 7, further testing would have been required to determine which of those two compounds was actually effective in treating ED. As the trial judge stated, at para. 146, “[a] skilled reader would then conduct tests on those two compounds and determine which of those compounds worked.” And as he also stated, at para. 135, “the skilled reader must undertake a minor research project to determine which claim is the true invention”.
As a result, the Supreme Court held that “Patent ’446 is invalid”[87] and “Patent 2,163,446 is void”[91].
Interestingly, the underlying proceeding was a prohibition proceeding under the Patented Medicine (Notice of Compliance) Regulations, in which success by the generic company is a finding that its allegations of invalidity (or non-infringement) are justified, rather than a finding that the patent is invalid (in rem) as announced by the Supreme Court in this decision. Even after an unsuccessful proceeding under the PM(NOC) Regulations, a patent owner may bring a patent infringement action against the same generic.
An example of contrary decisions is with Plavix, where the Supreme Court held (in 2006 SCC 61) that Apotex’s allegations of invalidity were not justified in the PM(NOC) proceeding but in a later patent impeachment action, the same patent was held invalid (in 2011 FC 1486 – subject to a pending appeal).
Teva has already announced the availability of its generic version of Viagra as a result of the ruling. Some have seen the humourous side of the subject matter of this decision. Articles on the decision are available from the Globe and Mail, National Post and CBC.
This decision will likely have significance for patent owners and patent agents preparing patent applications, requiring that sufficient disclosure of the invention be included in the patent application as well as providing additional grounds to challenge the validity of patents.
More information on other intellectual property proceedings at the Supreme Court are available on my Supreme Court litigation page.
[Update: According the SCC docket, Pfizer’s counsel has indicated that a motion for reconsideration – likely on the declaration that the patent is void – will be filed.]