Federal Court of Appeal Reinstates Validity to PLAVIX Patent

The Federal Court of Appeal (Court) recently reversed the Federal Court’s decision in Apotex Inc v Sanofi-Aventis 2011 FC 1486, and held Canadian Patent No. 1,336,777 (‘777 Patent) to be valid and to have been infringed by the respondent Apotex. At issue in the appeal was the validity of the ‘777 Patent with respect to obviousness and lack of utility. This recent decision which relates to impeachment and infringement proceedings under the Patent Act discusses two of the recently most litigated concepts in patent law: “obvious to try” and “promise of the patent”. The ‘777 Patent is a selection patent relating to a single compound, clopidogrel, which was selected from the compounds claimed by the genus patent, Canadian Patent No 1,194,875 (‘875 Patent). More specifically, clopidogrel is one compound of a racemic compound referred to as PCR 4099. (Racemic compounds are comprised of two compounds known as enantiomers, which are molecularly structural mirror images of one another). Clopidogrel is the active ingredient in PLAVIX®, a drug indicated for prevention of heart and vascular diseases. At the trial level, it was found that clopidogrel was more pharmacologically active and better tolerated than either the other enantiomer of PCR 4099 or PCR 4099 itself. Regarding obviousness, the question for the Court was whether clopidogrel was obvious in light of PCR 4099 and the ‘875 Patent. Apotex argued that the invention of the ‘777 Patent was obvious to try because methods for separating racemic compounds were known at the relevant time. However, the Court held that although methods of separating racemic compounds were known, it would not have been obvious to those skilled in the art to attempt to separate such compounds in the first place, given that one would not be able to predict the properties of the respective enantiomers before separating them. Regarding utility, at trial the Court had held that the ‘777 Patent promised that clopidogrel would be effective in treating human patients and that Sanofi had not demonstrated or soundly predicted this promised utility as of the filing date. In holding that the ‘777 Patent had utility, the Court of Appeal held that no such promise was given and the trial Court had improperly imported this promise into the patent:

[66] While these “indications” are consistent with human use, they are not inconsistent with other uses. ... [The Court below] erred in law in reading into the ‘777 patent a promise for use in humans on the basis of inferences, in the absence of language at least as clear and unambiguous as that used to establish the advantages of the selection over the compounds of the genus patent.

The Court of Appeal decision brings this case in line with the Supreme Court of Canada’s decision regarding the ‘777 Patent under the Patented Medicines (Notice of Compliance) Regulations (Regulations) which upheld the ‘777 Patent. For the full decision see: http://canlii.ca/t/fzslc For more commentary see: http://tinyurl.com/lz2dlk9 Summary by: Thomas Wong