On June 10, 2013, the Canadian Intellectual Property Office (CIPO) released examination guidelines on medical use claims. In particular, the guidelines focus on examination of medical use claims that recite dosage regimens or dosage ranges.

The guidelines affirm CIPO’s long-standing position that methods of medical treatment are unpatentable. The guidelines then go on to explain that medical use claims are generally permitted, as long as they do not “equate” to a medical or surgical method (e.g. do not include an active treatment or surgical step) that would prevent physicians from exercising their skill and judgment.

The guidelines build on recent guidelines on purposive construction.  As reported in an earlier article, the assessment of statutory subject matter is based on the essential elements of a claim as determined by a purposive construction of the claim.  The problem and solution addressed by the inventor are identified, to assist with determining the essential elements that provide the solution to the problem.  Practices relating to the “contribution” of a claim are not to be followed.

The guidelines advise that, in the case of medical-related subject matter, “[w]here an essential element only serves to instruct a medical professional ‘how’ to treat a patient, rather than ‘what’ to use to treat the patient, this will lead to the conclusion that the claimed use encompasses a method of medical treatment” and thus is not considered patentable.  Further, if it is determined that “ a dosage regimen or dosage range is an essential element of a claim encompassing the use of a known compound in an established treatment, then the claim covers a method of medical treatment”.

While the guidelines provide practical guidance as to what CIPO will consider in assessing medical use claims for statutory subject matter, patentability will turn on the facts of each case.