The Federal Court of Appeal Reverses Finding of Infliximab Patent Infringement

In Hospira Healthcare Corporation v. Kennedy Trust for Rheumatology Research, 2020 FCA 30, the Federal Court of Appeal (“FCA”) allowed an appeal of the decision of the Federal Court in 2018 FC 259, which concluded that Canadian Patent No. 2,261,630 (“the 630 Patent”) was valid and infringed. In allowing the appeal and reversing the Federal Court’s decision in part, the FCA provided clarification regarding a number of legal issues, including anticipation and obviousness.

Background

The Kennedy Trust for Rheumatology Research (“Kennedy”) is the owner of the 630 Patent, which details the adjunctive use of methotrexate (MTX) and the anti-tumour necrosis factor-? (anti-TNF-?) antibody “infliximab” for the treatment of rheumatoid arthritis (RA) and other autoimmune disorders.

Hospira Healthcare Corporation (“Hospira”) commenced an action seeking to invalidate the 630 Patent and Kennedy counterclaimed for infringement on the basis that Hospira’s biosimilar Inflectra infringed the 630 Patent.

Anticipation

Among other things, section 28.2 of the Patent Act provides that the “subject-matter defined by a claim…must not have been disclosed…before the claim date…in such a manner that the subject-matter became available to the public”. Section 28.2 thus creates a requirement that the subject matter defined by a claim is novel (or not anticipated).

The FCA considered Hospira’s argument that the trial judge erred in finding that two prior art references (The Kennedy Report 1994 and Higgins) were not anticipatory because they did not describe the “special advantage” of the 630 Patent. The trial judge noted that The 1994 Kennedy Report disclosed the idea of co-administration of MTX and infliximab, but that no results were yet available, and therefore the special advantage of such adjunctive therapy was not disclosed. Similarly, the trial judge found that, while Higgins discloses the possibility of combining an anti-TNF-? antibody with MTX, the anti-TNF-? antibody mentioned was not infliximab, and the paper did not disclose the special advantage of the combination, nor the doses or administration schedule of either drug.

The FCA held that the trial judge’s analysis was erroneous. In coming to its conclusion, the FCA stated that, “in order for any particular result from the claimed combination treatment to be a basis for distinguishing over the prior art, it would be necessary to conclude that such results constituted an essential element of the claim in question” (emphasis added). A particular result was not an essential element of the claims in question. Similarly, infliximab, the doses, and the administration schedule of either drug were also not essential elements of the claims in question. Accordingly, the trial judge erred by addressing whether subject matter that was not claimed (i.e., “special advantages”) had been disclosed before the claim date, which is legally irrelevant.

With respect to enablement, the FCA similarly emphasized that what must be enabled by the prior art are the essential elements of the claims, not the particular experiments disclosed in the impugned patent. The FCA further emphasized that there must be a balance when assessing sufficiency of disclosure of the impugned patent and enablement from the prior art. The skilled person must have the same aptitude and skills for the purposes of assessing enablement as he or she does for the purposes of assessing sufficiency.

Obviousness

Among other things, section 28.3 of the Patent Act provides that the “subject-matter defined by a claim…would not have been obvious on the claim date to a person skilled in the art…having regard to…information disclosed before the claim date…in such a manner that the information became available to the public”. Section 28.3 thus creates a requirement that the subject matter defined by a claim is not obvious to a skilled person in view of publicly-available information.

The trial judge excluded certain prior art references from the “state of the art” on the basis that, although they were available to the public at the relevant date, they would not have been found by the skilled person conducting a reasonably diligent search.

Recognizing that this was an area of the law of obviousness that required some clarification, the FCA held that the trial judge erred because section 28.3 of the Patent Act contemplates that the subject-matter defined by a claim not be obvious to a skilled person having regard to publicly-available information, without any limitation that the information would need to be locatable in a search.

The FCA also clarified the law regarding “obvious to try” by stating that, while being “‘more or less self-evident to try to obtain the invention’ is a requirement for obviousness to try, being ‘more or less self-evident that what is being tried ought to work’ is not a requirement but merely a factor to be considered” (emphasis added). Hence, the trial judge’s primary basis for finding that the subject matter of the claims was non-obvious (i.e., “it was not self-evident that this combination would work to solve the problem identified in the prior art”) was based on a wrong conception of the law.

Finally, the FCA also held that obtaining the claimed invention did not require the skilled person to be capable of designing or conducting the particular experiments described in the 630 Patent – it was enough for the skilled person to co-administer an anti-TNF-? antibody and MTX, as claimed, and observe the results. The results provided by those experiments were not part of the essential elements of the claims.

The approach of the FCA is consistent with the clear language of section 28.3 of the Patent Act that it is the “subject-matter defined by a claim” that must be non-obvious rather than unclaimed properties or results described in the disclosure of a patent.

Outcome

The appeal was allowed and the matter was remitted back to the Federal Court for reconsideration of the issues of anticipation and obviousness.

Authors: Jordan Scopa and Jaclyn Tilak