Canadian Patent Claims to Medical Uses: Practice Notice Updates

The Canadian Intellectual Property Office (CIPO) has released a Practice Notice regarding the examination of patent claims which relate to medical uses.1 The Practice Notice supersedes earlier guidance from CIPO, and serves to reflect the recent judgment of the Federal Court in AbbVie Biotechnology Ltd. v. Canada (Attorney General) (AbbVie).2 In AbbVie, the Court determined that CIPO’s prior examination practice of claims relating to medical uses did not comply with existing jurisprudence and was not supported by the Patent Act. This new Practice Notice brings CIPO’s examination practice in line with the jurisprudence in light of the AbbVie decision.

What You Need To Know

  • Patent claims that would restrict a medical professional’s exercise of professional skill or judgment remain not patentable in Canada. For example, a claim where a range of dosages and/or a range of dosing intervals is an essential element is not patentable, because medical professionals must select a particular dose or dosing interval based on professional skill and judgment.
  • Claims narrowed to the use of a fixed dosage, a fixed dosage regimen, a particular patient sub-population, or a particular administration site may be patentable according to the new Practice Notice, if the claim does not prevent, interfere with, or require the exercise of a medical professional’s skill or judgment. For example, a claim that specifies as an essential element the use of fixed dosages, repeated at fixed intervals, may be patentable.
  • Claims that include, as non-essential elements, dosage regimens involving ranges of either dosages or dosing intervals, may be patentable. For example, a dosage range may not render unpatentable a claim relating to a new chemical compounds or a new medical use of a previously known compound.

Background: CIPO’s Approach and AbbVie

It has been well established in Canada that patent claims restricting the exercise of a physician’s professional judgment and discretion in treating patients are not patentable subject matter under the definition of "invention" in section 2 of the Patent Act. Prior to AbbVie, CIPO considered claims reciting a dosage regimen comprising a fixed dosage plus a dosing interval, or a range of doses or intervals to fall within the purview of medical discretion, and therefore to be not patentable subject matter. In AbbVie, the Court determined that certain claims related to dosage regimens may be patentable, if no professional judgment or discretion were claimed. The Court determined that claims specifying a fixed dosage amount or dosage interval would not engage the professional judgment of a physician and are as such patentable.

The fixed dosage regimen in AbbVie involved a novel and unobvious regimen applied to a known drug substance for a known indication. Examples of the application of CIPO’s prior approach to examination of medical use claims emphasized that in the case of a new compound or a new use of a known compound, dosing regimens comprising ranges would be patentable, on the basis that the solution of the invention is a new compound or new use. Accordingly, it is likely that the new Practice Notice, and the prohibition on dosage regimens involving ranges, will be restricted to examination of claims relating to previously known uses of known compounds.


1 PN 2015-01:

2 AbbVie Biotechnology Ltd. v. Canada (Attorney General), 2014 FC 1251.

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