After the Federal Court found certain claims of Canadian Patent 1,341,206 (the '206 patent') relating to ramipril (Altace) to be invalid, Apotex sought relief in the Ontario Superior Court of Justice pursuant to the Ontario Statute of Monopolies, the UK Statute of Monopolies and the Trademarks Act. On February 6 2018 Justice Dunphy dismissed(1) motions by the defendants Sanofi and Schering for leave to amend their statements of defence following the recent Supreme Court decision in AstraZeneca Canada Inc v Apotex Inc.(2)

The defendants sought to plead that they should not be estopped or otherwise precluded from taking the position that Apotex could not rely on the earlier Federal Court decision invalidating the patent at issue, which was arguably wrong in view of AstraZeneca. In AstraZeneca, the Supreme Court had struck down the promise doctrine as "incongruent with both the words and the scheme of the Patent Act" (for further details please see "Promise doctrine struck down and AstraZeneca's NEXIUM patent upheld as useful").

Dunphy relied on the doctrines of issue estoppel and collateral attack in denying Sanofi and Schering leave to amend. He distinguished jurisprudence indicating that an exception to these doctrines is available only in special circumstances (ie, in the event of a change in the law). In his view, AstraZeneca had not resulted in a change in the law, but merely a change in an "aspect of the interpretation of a statutory provision that was not amended." In light of AstraZeneca, it was arguable, but not certain, that the Federal Court's earlier decision was in error. Further, allowing the proposed amendments would effectively require relitigation of the entire issue previously decided at trial (ie, the validity of the 206 patent). Dunphy also dismissed the motions on the alternative basis of Sections 62 and 63 of the Patent Act. In his view, the appeal available under Section 63 is the only avenue "by which a patent that has been declared to be void can be treated otherwise".

For further information on this topic please contact Brandon Heard at Smart & Biggar/Fetherstonhaugh by telephone (+1 416 593 5514) or email ( The Smart & Biggar/Fetherstonhaugh website can be accessed at


(1) Apotex v Schering Corporation, 2018 ONSC 903.

(2) 2017 SCC 36.

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