Sildenafil patent not “void”

The Supreme Court of Canada has varied its decision in Teva Canada Ltd. v. Pfizer Canada Inc., 2012 SCC 60 to remove references to the patent being ‘invalid’ or ‘void’ and instead referred to Teva’s allegations of invalidity in the PM(NOC) application being established.

In November, the Supreme Court issued its decision in Teva Canada Ltd. v. Pfizer Canada Inc., 2012 SCC 60 holding that Pfizer’s patent on sildenafil/Viagra was invalid for having an insufficient disclosure contrary to s.27(3) of the Patent Act.

Pfizer brought a motion for re-hearing or to vary the decision because the underlying proceeding was an application under the Patented Medicine (Notice of Compliance) Regulations where the court determines if allegations of invalidity and non-infringement are justified rather than invalidity of the patent in rem.

In yesterday’s decision (PDF), the Supreme Court varied the decision in the following manner:

  1. Added the following line to the first paragraph:

    This appeal involves a challenge to the validity of the patent of the Pfizer respondents (“Pfizer”) for Viagra, a drug currently on the market for treating erectile dysfunction (“ED”). On August 24, 2007, Pfizer brought an application before the Federal Court under s. 55.2(4) of the Patent Act, R.S.C. 1985, c. P-4, and under s. 6(1) of the Patent Medicines (Notice of Compliance) Regulations, SOR/93-133 (“Regulations”), for an order prohibiting the Minister of Health from issuing Teva a Notice of Compliance (“NOC”) for its generic version of Viagra. The appellant, Teva Canada Limited (“Teva”), claims that Pfizer’s patent application did not meet the disclosure requirements set out in the Patent Act, R.S.C. 1985, c. P-4 (the “Act”). Pfizer, on the other hand, submits that it complied fully with those requirements.

  2. In paragraph 83 made the following amendment:

    In the case at bar, Patent ’446 is insufficient, because a skilled reader having only the specification would not be able to put the invention into operation. Therefore, Patent ’446 is invalid.Therefore, I find that the appellant has established its allegation under ss. 5(1)(b)(iii) and 5(3) of the Regulations that Patent ’446 is not valid.

  3. In paragraph 87, made the following amendment:

    Although wilful intent to mislead has not been alleged or proven in this case, insufficient disclosure has been alleged and I have found that it has been made out. Therefore, in light of the remedy adopted in Pioneer Hi-Bred, Patent ’446 is invalid. Therefore, in the light of the remedy in Pioneer Hi-Bred, as I mentioned above, I hold that Teva has established its allegation that Patent ’446 is not valid.

  4. The final paragraph of the decision is amended:

    I would therefore allow the appeal with costs and hold that Patent 2,163,446 is void. Therefore, I would allow the appeal with costs and hold that Teva established its allegation that Patent 2,163,446 is not valid, and dismiss Pfizer’s application for an order of prohibition under s. 6(1) of the Regulations.

The Court also granted, in-part, Teva’s motion adding “with costs in this Court and in the courts below” to both the reasons and formal order. Howard Knopf posted copies of Pfizer’s Notice of Motion and Factum and Teva’s Response in the motion for re-hearing. Thanks to Andy Shaughnessy for a copy of the yesterday’s decision.

Since the date of the original Supreme Court’s decision, Justice Zinn declared the 446 patent invalid (in Apotex Inc. v. Pfizer Ireland Pharmaceuticals 2012 FC 1339), in an impeachment action brought by Apotex. This decision has been appealed (see A-560-12).

2 thoughts on “Sildenafil patent not “void””

  1. Dear Alan,

    I am confused. Can you please elaborate the above case. As in title it says “sildenafil patent is not void” while i read below, it says teva Therefore, in the light of the remedy in Pioneer Hi-Bred, as I mentioned above, I hold that Teva has established its allegation that Patent ’446 is not valid.

    Regards,
    Sanjay

  2. Hello Sanjay,

    The distinction arises from the differences between regulatory proceedings under the Patented Medicine (Notice of Compliance) Regulations and patent actions (either patent infringement or patent impeachment). Only decisions in patent actions are ‘in rem’ and can invalidate the patent.

    Regards,

    Alan

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