The Federal Court of Appeal (FCA) has dismissed appeals concerning two actions brought under the Patented Medicines (Notice of Compliance) Regulations (Regulations), confirming the Federal Court (FC) holding that claims to uses of the molecule fampridine were invalid. The FCA’s decision provides guidance on claims construction and analyzing obviousness, while pointedly refusing to endorse the FC’s conclusions on anticipation.


Biogen markets FAMPYRA®, a fampridine sustained release (SR) composition, in Canada. Taro and Pharmascience sought to bring generic fampridine SR products to the Canadian market. In response, Biogen asserted Canadian Patent No. 2,562,277 (the 277 Patent) against Taro and Pharmascience, bringing a patent infringement action against each under subsection 6(1) of the Regulations. Both Taro and Pharmascience challenged the 277 Patent, alleging that the asserted claims were invalid for, inter alia, anticipation and obviousness. The FC heard the invalidity issues in the two actions concurrently. As we reported, the FC found that all of the asserted claims were invalid for obviousness and that four of the claims were also anticipated by the Acorda S-1 reference.

Claims construction: recourse to the description

The asserted claims in the 277 Patent relate to twice-daily use of 10 mg fampridine SR, for a period of at least two weeks, for improving walking (or for increasing walking speed) in a subject with multiple sclerosis (MS) in need thereof.

On appeal, Biogen argued that the FC had erred in construing the claim terms “for improving walking” and “for increasing walking speed”. The FC had found that these claim terms only required a statistically-significant, quantitative improvement in walking or increase in walking speed.   But, according to Biogen, these claim terms also had a subjective component: the subject with MS had to perceive that the fampridine SR regimen improved their walking or increased their walking speed. Therefore, by not including this subjective component in the claims, the FC had improperly narrowed the gap between the claimed subject matter and the prior art (which allegedly taught away from a subjective benefit for the claimed regimen).

The FCA upheld the FC’s construction. In doing so, the FCA held that a patent’s description must be considered when construing its claims, even for claim terms that would appear at first glance to be simple and unambiguous. In this light, the FCA conducted a detailed analysis of the language of the claims, the description, and the expert evidence to reject Biogen’s argument that the asserted claims had a subjective component.

Obviousness: no reviewable error

Biogen’s appeal on obviousness focused on the FC’s purported failure to adopt the perspective of the person of skill in the art (POSITA), particularly the POSITA’s skepticism of prior art MS treatments that were not supported by double-blind, placebo-controlled trials.

The FCA rejected Biogen’s arguments, finding that there was sufficient evidence to support the FC’s conclusions. In particular, the FC did not err in finding that, although skeptical, the POSITA would have been willing to learn from and have been motivated by the prior art on MS treatments.

Anticipation: no comment?

Given that the asserted claims in the 277 Patent were all obvious, the FCA declined to address the FC’s findings on anticipation. However, the FCA also cautioned that “it is important to recall that nothing in these reasons… should be understood as endorsing the conclusion of the Federal Court on anticipation.”

This comment is notable because the FC’s conclusion on anticipation raises the broader question of whether public disclosure of a planned or ongoing clinical trial for a new use of a drug will anticipate any patent that is based on the successful outcome of that clinical trial. As we reported, the FC found this to be the case on the facts, including the Acorda S-1 reference, and in light of the FCA’s earlier decision in Hospira Healthcare Corporation v. Kennedy Trust for Rheumatology Research, 2020 FCA 30 (Hospira).

Though the FCA declined to engage with the merits of the anticipation issue, it stated that (i) Hospira was not “intended to modify the well-established test” for anticipation; and (ii) this is not the “proper case to address” how Hospira “might have an impact on inventions requiring investments in large clinical trials”.

Admissibility of expert report

Finally, the FCA rejected Biogen’s argument that the FC erred by not declaring the defendants’ expert report inadmissible because approximately 100 paragraphs of it had been copied nearly verbatim from Taro’s Notice of Allegation (which the expert had never reviewed). The FCA found that the FC had properly considered this fact in weighing the expert’s evidence; this was not an egregious case or one of those rare cases warranting striking an expert report.

Links to decisions:

Trial decision: Biogen Canada Inc v Taro Pharmaceuticals Inc, 2020 FC 621

Appeal decision: Biogen Canada Inc. v. Pharmascience Inc., 2022 FCA 143