On April 23, 2015, the Supreme Court of Canada denied leave to hear an appeal from the Federal Court of Appeal decision in Apotex Inc v Pfizer Canada Inc, et al and Mylan Pharmaceuticals ULC v Pfizer Canada Inc, et al, 2014 FCA 250 (the Court of Appeal decision). As there has been much discussion in the area of law surrounding utility and the "promise of the patent", guidance from the Supreme Court of Canada would have been welcome. However, the decision reached by the Federal Court of Appeal in this case takes a balanced approach to determining whether a patent contains an invalidating unfulfilled promise.

The leave applications relate to Canadian Patent No. 2,177,576 (the '576 Patent), which expired on November 14, 2014. The '576 Patent was directed to a new class of non-steroidal anti-inflammatory drugs (NSAIDs) and claimed new compounds including celecoxib, sold by Pfizer under the name Celebrex, and their associated uses. Pfizer sought orders prohibiting the Minister of Health from issuing a Notice of Compliance to Apotex and to Mylan in respect of their generic versions of the drug Celebrex. The Federal Court allowed both of Pfizer's applications and issued prohibition orders against Mylan (2014 FC 38) and Apotex (2014 FC 314). Apotex and Mylan appealed the orders. The appeals were consolidated and refused by the Federal Court of Appeal.

Apotex advanced four distinct arguments before the Court of Appeal: i) lack of utility in treating inflammation in humans, ii) lack of utility in reducing side effects, iii) lack of utility in preventing colorectal cancer, and iv) insufficient disclosure. Mylan's submissions focused on an argument of lack of utility in reducing side effects. The parties also alleged that the Federal Court breached the principles of comity and stare decisis in failing to follow the construction of the '576 Patent reached by Justice Hughes in GD Searle & Co v Novopharm Ltd (2007 FC 81) and affirmed by the FCA (2007 FCA 173). Further, the parties argued that it was abuse of process for the Federal Court judge to accept Pfizer's pleading that reduced harmful side effects were not promised as it had conceded that point in the Novopharm decision.

Justice Noël began his analysis by stating that the minimum statutory requirements for utility are quite low - no more than a "scintilla" - and the promise doctrine is an exception to this standard. An inventor need not describe any particular utility and will be held to a higher utility standard only where a "clear and unambiguous" promise has been made. Further, when allegations of unfulfilled promises regarding a patent are made, the patent will be construed in the patentee's favour where it can reasonably be read by a skilled person to exclude any such promises.

Apotex argued that where a patent "lays claim" to a particular use, that use must form part of the promise. Justice Noël rejected this broad proposition, stating "when a result or advantage is asserted in a patent's claims, it will generally be seen as a promise of utility." Apotex had failed to establish that any of the '576 Patent's claims describe use in humans as an advantage of the claimed compounds and the '576 Patent made no explicit promise of treatment in humans. Justice Noël also rejected the parties assertions that the '576 Patent promised utility in reducing side effects.

Apotex further argued that any given promise must be construed as overarching and, since the promise of preventing colorectal cancer was neither demonstrated nor soundly predicted as of the filing date, the patent as a whole should be invalidated. The Court of Appeal held that there was no support in the jurisprudence for this proposition. At most, the cases cited by Apotex demonstrate that a promise may be construed to extend to each of the patent's claims and there was no general statement of law made on the matter.

Regarding sufficiency of disclosure, Apotex's asserted that Pfizer concealed its "true invention" among a group of compounds that it knew were not useful, resulting in insufficient disclosure. This was rejected since Apotex had not advanced these arguments in its Notice of Allegation.

Additionally, the appellants had argued at the Federal Court that Pfizer was abusing the process of the court as it had conceded in the Novopharm NOC proceeding that reduced side effects were necessary to the utility of the '576 Patent. Apotex asserted that a party cannot elevate an inventive concept to support non-obviousness and read then it down in the utility analysis, that a party cannot take inconsistent positions in different proceedings, and that a party cannot re-litigate an issue previously decided with the aid of additional evidence it chose not to adduce in the earlier proceeding. The Court of Appeal dismissed these arguments, stating that there may be instances where a concession made in one proceeding may be binding in another, but there is no existing precedent on point and Federal Court judge had not committed any error in exercising his discretion to hold otherwise.

Apotex and Mylan further asserted that under the doctrine of stare decisis, the Federal Court was bound by the construction of the '576 Patent reached by Justice Hughes and upheld by the Court of Appeal in the Novopharm decision. There, it was held that a promise of reduced side effects had been made. Justice Noël emphasized that the doctrine of stare decisis obliges courts to render decisions that are consistent with previous decisions made by higher courts. However, not every statement in a given judgment is binding on lower courts. An appellate judgment will be authoritative for its ratio decidendi, the reasoning necessary to reach a decision on the issues litigated. Statements of obiter dicta will vary in authoritative force from helpful commentary to guidance. The Novopharm Court of Appeal decision did not decide that reduced side effects were necessary to the utility of the '576 Patent, rather, it decided two narrow issues relating to the correct claim date and a point of obviousness. Thus, there is no authoritative decision relating to utility of reducing side effects reached by a higher court that would have bound the Federal Court in subsequent litigation.

Regarding the doctrine of comity or horizontal stare decisis, Justice Noël reiterated that decisions reached by judges of the same court are not binding on each other. There may be uncertainty created when two judges reach distinct results on the same question of law. However, there is no legal sanction for a judge's failure to abide by comity.

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