Pharmaceutical Patents And Canada's Prohibition On Patenting Methods Of Medical Treatment: A Predictable Pattern To Follow?

There is a paucity of comprehensive analysis on the Canadian jurisprudence that has shaped the prohibition of methods of medical treatment from patentability. Contrary to the United States, methods of medical treatment have long been considered non-patentable subject matter in Canadian patent law. The prohibition, however, is not absolute: certain cosmetic and natural condition treatments 1, medical devices 2, diagnostic methods 3, and pharmaceutical claims 4 are patentable.

Despite extensive discussion by our courts, the reasons behind why such a prohibition exists remain unclear for both courts and patent lawyers. Similarly, the distinction between non-patentable methods of medical treatment and patentable claims before CIPO is sometimes unclear. The confusion is so great that the Federal Court of Appeal recently called for a full consideration of the prohibition by the Supreme Court of Canada in Bayer Inc v Cobalt Pharmaceuticals Co 5. Whereas some have asserted that the prohibition is variable and ever-changing 6, to the best of the authors' knowledge, no scholarly publication currently exists that systematically reviews the entire breadth of Canadian case law concerning methods of medical treatment in the context of pharmaceutical patents up to and including 2018. After careful review of the relevant jurisprudence, it seems that while the rationale for the prohibition sits on shaky legal ground, there is a clear pattern in the way that the prohibition has been applied by the courts.

In light of the ongoing need for access to effective drugs for medical prescription in Canada, the patenting of new pharmaceutical innovation is of real use and benefit to all Canadians. Thus, this article focuses on the Canadian prohibition in the context of pharmaceutical claims in order to provide a clear understanding for patent agents and inventors alike of this confusing patent landscape, such that they may better prepare pharmaceutical patent claims that do not claim prohibited subject matter.

Have the courts ruled in an inconsistent fashion following the establishment of the prohibition on the patentability of methods of medical treatment?

To answer this question, the primary author performed a retrospective study on cases that concerned the prohibition following its establishment in the context of pharmaceutical patents on 19 November 1991 7. The study's objective was to determine whether any predictable pattern to the decisions could be found.

The...