Canada: Court Of Appeal Again Interprets Utility Requirement In Celebrex FCA

Introduction

The Federal Court of Appeal has again discussed the so-called "promise doctrine" in its October 30, 2014 decision of Apotex Inc. v. Pfizer Canada Inc., 2014 FCA 250 (Celebrex FCA). Celebrex FCA reasons that promises should be found only in circumstances where they are explicitly made. Celebrex FCA also holds that promises can only apply to those claims to which they directly relate. Celebrex FCA is especially of interest given the upcoming arguments before the Supreme Court regarding utility and the promise doctrine in Plavix.¹

The Patent at Issue

Canadian Patent 2,177,576 (the '576 Patent) was at issue in Celebrex FCA. Of relevance is the fact that the '576 Patent contains claims to classes of novel compounds (claims 1-3, 7), individually claimed compounds, including the commercial compound celecoxib (claims 4-6), therapeutically-effective amounts of the claimed compounds (claim 8), and uses of the claimed compounds; in particular, the use to treat inflammation and inflammation related diseases in a subject (claims 9-15), and the use to prevent colorectal cancer (claim 16).

The claimed compounds were said to preferably be "COX-II inhibitors". A person skilled in the art knew that a selective COX-II inhibitor would potentially have lower side-effects than compounds that did not discriminate and inhibited both COX-I and COX-II. With this in mind, the patent's disclosure stated "The compounds are useful as antiinflammatory agents, such as for the treatment of arthritis, with the additional benefit of having significantly less harmful side effects" and "Such preferred selectivity may indicate an ability to reduce the incidence of common NSAID- induced side effects."

The Decisions Below

Celebrex FCA considered two related appeals under the PM (NOC) Regulations from decisions of Justice Harrington. In the first decision, Celebrex Mylan,² Harrington J. considered an argument that the '576 Patent promised reduced side effects, and that this promise was not in fact kept. Harrington J. rejected this argument for two reasons. First, the disclosure did not contain an explicit, unequivocal promise; only a possibility of reduced side effects was contemplated. Second, the claims themselves did not mention reduced side-effects. Given these factors, reduced side-effects was said to be a goal or advantage rather than a promise.

The second decision under appeal was Celebrex Apotex.³ Apotex argued that the use claims promised treatment of inflammation in humans (rather than "subjects", as was claimed); that reduced side-effects was a promise that pervaded all of the '576 Patent's claims; that the entire patent lacked utility because the use of claim 16, to prevent colorectal cancer, was not established; and that the '576 Patent did not meet the Patent Act's section 27(3) sufficiency requirements. Again rejecting these arguments, Harrington J. found that:

• Use in humans to treat inflammation and a promise of reduced side-effects was not claimed;
• While claim 16 lacked utility, section 58 of the Patent Act meant that the invalidity of this claim did not impact the validity of the other claims of the '576 Patent; and
• The '576 Patent's true invention was a class of compounds effective as COX-II inhibitors, and thus that the '576 Patent sufficiently disclosed the invention.

The Court of Appeal's Decision

Writing for the entire panel (Trudel and Boivin JJA), Noël CJA made several interesting observations in his discussion regarding the utility of the '576 Patent. In particular, guidance was provided regarding how so-called "promises" should be appropriately construed.

The FCA stated that the general rule is that the only statutory utility requirement is found in section 2 of the Patent Act, and that section 2 only requires that a "scintilla" of utility be established. While it was found that explicit promises of specific results can represent an exception to this rule, Noël CJA cautioned courts not to be overzealous in reading in promises, stating that promises will be found "only where a clear and unambiguous promise has been made." In clarifying what constitutes a "clear and unambiguous promise", the FCA linked the Supreme Court's Consolboard⁴ guidance that courts, when possible, should afford protection for what was in good faith invented with Plavix FCA's dicta that promises must be "explicit". Applying this, it was stated that patents challenged on the basis of unfulfilled promises "be construed in favour of the patentee where it can be reasonably read by the skilled person as excluding this promise" and that promises will not be found if they "can only be supported on the basis of equivocal inferences and ambiguous indications."

The FCA implemented the above principles on the facts of this case to find that Harrington J. was correct in not extending the use of treating inflammation to humans, as such use was not claimed. Harrington J.'s finding that the '576 Patent made no explicit promise of reduced side effects was also upheld.

There are two other noteworthy aspects of Celebrex FCA. First, it was noted that promises do not necessarily pervade all claims of a given patent. As mentioned, the '576 Patent contained compound claims and use claims, with the use claims going to separate uses. The FCA upheld Harrington J. in finding that the lack of utility with respect to claim 16, which claimed the use of the compounds for preventing colorectal cancer, did not impact the utility of other claims, such as claim 4 (to the compound celecoxib) or claim 10 (to the use of the claimed compounds for treating inflammation in a subject). As noted in the reasons, this is entirely consistent with Gleevec⁵ and with the section 58 requirement in the Patent Act.⁶

Second, Celebrex FCA is consistent with Viagra⁷  and esomeprazole⁸ in finding that there is no need for an inventor to disclose his or her utility, including in cases of sound prediction. On this point, Noël CJA stated "the inventor need not expressly set out the utility of the invention in the patent...it is merely required that, where the inventor is called upon to prove the utility of the invention, utility can be shown to be demonstrated or soundly predicted as of the patent's filing date." This passage is consistent with the emerging recognition of the distinction between the Patent Act's section 2 utility and section 27(3) disclosure requirements.

The Celebrex FCA decision can be found here.

Footnotes

1 Case number 35562, on appeal from 2013 FCA 186.

2 2014 FC 38. Discussed here.

3 2014 FC 314

4 [1981] 1 SCR 504 at 521.

5 2013 FC 141

6 As recently applied in Viagra, 2012 SCC 60 at para 42.

7 At paras 38-40.

8 2014 FC 638 at paras 139-161.

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