Methods Of Medical Treatment: Still Not An 'Invention' In Canada

On January 27, 2014, the Federal Court of Appeal in Novartis Pharmaceuticals Canada Inc. v. Cobalt Pharmaceuticals Co., 2014 FCA 17 (Novartis), upheld the Federal Court's denial of an application for a prohibition order under the Canadian Patented Medicines (Notice of Compliance) Regulations on the basis that the impugned patent was directed to a method of medical treatment. With this third decision1 on alleged methods of medical treatment in the past year alone, Canadian courts continue to hold methods of medical treatment to be unpatentable, while providing only limited guidance about the limits of permissible claiming.

In Novartis, the claims at issue were directed to a particular frequency of dosing zoledronic acid to treat osteoporosis, namely intermittent administration about once a year. For example, claim 16 was directed to "use of zoledronic acid for the treatment of postmenopausal osteoporosis wherein the zoledronic acid ... is in a unit dosage form of about 5 mg which is administered intermittently, with a period of about one year between the first and each subsequent administration, wherein each administration is intravenous." Of note, the Federal Court had found that the dosing frequency was the sole aspect of the invention that made it not obvious. The issue, therefore, was whether a dosing frequency falls within the scope of patentable subject matter set out in the definition of "invention" in section 2 of the Patent Act.

Consistent with European practice, Canadian courts have long found methods of medical treatment to be unpatentable, even after the Patent Act's former prohibition against patenting drug substances was repealed. Relying on the 1972 decision of the Supreme Court of Canada in Tennessee Eastman Company v. Commissioner of Patents, [1974] S.C.R. 111, which involved a surgical method for joining incisions by applying certain compounds, Canadian courts have found the following subject matter, for example, to be unpatentable: dosage ranges dependent on a patient's weight,2 a titration regime,3 and use claims where components and dosages need to be selected.4 The courts' rationale appears to be that Canadian patents ought not interfere with the ability of physicians to exercise their skill and judgment.

In Novartis, the Federal Court of Appeal had the opportunity to clarify what exactly amounts to an unpatentable method of medical treatment. Unfortunately, the four paragraph decision does little more than affirm the...