The Federal Court of Appeal clarified in Pharmascience v. Bristol-Myers Squibb, 2022 FCA 142, that the specification of the issued patent, not the specification before the Canadian Intellectual Property Office prior to issuance, is relevant to the analysis of the sufficiency of the patent’s disclosure.
Locke JA, writing for the FCA, considered appeals from BMS v. Pharmascience, 2021 FC 1 in which Patent Nos. 2,461,202 and 2,791,171 were both held valid. The patents concern apixaban, a Factor Xa inhibitor and anticoagulant for treating thrombosis marketed by BMS as ELIQUIS.
The FCA deliberated whether the disclosure of the 202 Patent was insufficient pursuant to s. 27(3) of the Patent Act for not correctly and fully describing the invention as of the filing or publication date. The application for the 202 Patent, as filed and published, described and claimed a multitude of Factor Xa inhibitor compounds without any specific focus on apixaban, which was included in one of over one hundred examples in the description. Claims directed to apixaban were only added to the application almost 10 years after the application was filed and shortly before the 202 Patent issued.
Issued vs. Pending?
Pharmascience argued that the 202 Patent is invalid for insufficiency because the application disclosure did not single apixaban out from among thousands of described compounds when it was filed or published. Pharmascience asserted that the lower court inappropriately based its analysis on the claims of the issued 202 Patent despite the decision of Justice Hughes in Zoledronate which, in Pharmascience’s view, stands for the proposition that the application as of the publication date is to be considered for sufficiency. Pharmascience contended that filing a patent application which does not describe the invention is unfair to the public.
Locke JA noted that the discussion concerning the relevant date for sufficiency in Zoledronate was obiter dicta. He emphasized that Zoledronate relied on the wording of a foreign statute and did not consider a Federal Court decision which concluded that the patent specification at the date of issuance is relevant for sufficiency. Finally, Locke JA noted that the Supreme Court authority on sufficiency, Pioneer Hi-Bred, contains “no suggestion that the specification must meet [the sufficiency] requirement at the application date, and cannot be amended during prosecution to comply”.
The FCA affirmed the lower court holding that a sufficiency analysis considers the issued and not pending claims. Locke JA reasoned that other patent validity questions, such as novelty, obviousness, utility and claim construction, are determined based on claims of the issued patent, not claims as they stood at some prior date. He noted this approach is consistent with Sildenafil, which found insufficiency based on the issued patent, and with provisions of the Patent Act which allow amendments to bring applications into compliance with sufficiency requirements in s. 27(3).
The parties had not argued at trial whether the addition of claims specific to apixaban was a permitted amendment or whether this improperly introduced new matter to the 202 Patent specification. Nonetheless, Locke JA suggested that an example in the description relating to apixaban and how to make it would likely have provided sufficient support for the late-added claims. He noted that “[i]t is common for patent applications to be filed claiming a broad range of embodiments described in the disclosure, only to be significantly narrowed prior to issuance” and that BMS had “clearly focused on apixaban (among other compounds) prior to the filing date”.
Relevant Date for Sufficiency Assessment
The FCA noted that “[i]t is important to draw a distinction between the date for determining sufficiency and the claims to be considered in that determination”, but did not comment on the lower court’s finding that sufficiency is assessed by the skilled person at the date of publication.
The FCA affirmed Zinn J’s holding that the disclosure of the 202 Patent was sufficient and that both the 202 Patent and the 171 Patent are valid. The appeals were dismissed with costs.
The decision can be found here.