Northern Exposure: Pfizer Canada’s Viagra® Patent Invalidated

Northern Exposure is a new series of articles that will focus on Canada and Canadian intellectual property laws, cases and procedures. From time to time we will also publish a Canadian perspective on important issues relating to US and Global intellectual property. For more articles please visit Northern Exposure – Canadian IP.

The Supreme Court of Canada rendered a decision on November 8, 2012 effectively canceling Viagra® Canadian patent a year and a half before its natural expiration date. This ends Pfizer’s exclusivity on the blockbuster erectile disfunction drug and opens the market up to generics. While certainly a press- worthy event, this decision does not change the Canadian patent landscape – but rather reinforces it.

The story begins when Teva Canada Limited, a generic company, filed for a “notice of compliance”, arguing that vague claims in the Pfizer patent would allow it to essentially produce a generic version of Viagra® through the backdoor. Normally, in a case where the “notice of compliance” is allowed, Teva Canada Limited would have been given the sole right to begin producing generics. The patent, however, would not be considered void. The Federal Court rejected the notice, so Teva appealed the decision to the Federal Court of Appeal and finally to the Supreme Court of Canada. The climb up the ladder essentially brought the case against the patent to a new level of scrutiny and interpretation.

Justice J. LeBel concluded not that Teva Canada Limited be granted the “notice of compliance”, but that Patent 2, 163, 446, popularly known as the Viagra® patent, be voided, allowing not only Teva Canada Limited, but any generics manufacturer to begin producing Viagra® clones. The reason: in none of the seven claims does the patent point to the exact compound that “induces penile erection in impotent males”. This exact compound, sildenafil, is mentioned alongside many others that do not cause the desired side effect.

By not disclosing the specific compound, the patent does not in a “full, clear, concise and exact” manner adequately describe the technology.

Furthermore, Justice LeBel clarified that the patent system is a “bargain”. Companies that develop innovative technologies are allowed exclusive rights for a limited time as long as they disclose the “how-to’s” for the public good. By not disclosing the specific compound that resulted in the technology’s stated innovation, Pfizer Canada was not sharing this “know-how” and broke their side of the bargain. As is so eloquently stated in the Supreme Court of Canada’s published decision: “If there is no quid — proper disclosure — then there can be no quo — exclusive monopoly rights.”

More than anything, this last line can perhaps describe an element of the Canadian patent system that is often forgotten. In the rush to capitalize and monopolize, it is easy to forget that patents are not only a boon to the patent holders but to society. They are published for a reason, and that reason is to disseminate new innovations for the benefit of society. Time-sensitive exclusivity is simply a pat on the back for all the hard work and a job well done. Teva Canada Limited v. Pfizer Canada Inc. is also a warning to all that clarity and sufficient disclosure is essential in the redaction of patent applications to result in valid patents. The Viagra® patent is a potent example of a failure in clarity and lack of disclosure. The case is an exception that should not affect well-written patents.

Update: Only days after the decision was issued, Pfizer Canada has now asked the Supreme Court to overturn their decision, claiming the Court overstepped its bounds. It would be fairly unprecedented for the Supreme Court to reconsider a ruling, so it can safely be assumed that it will stand.