On March 18, 2015 the Canadian Intellectual Property Office issued a practice notice containing revised examination practice guidelines pertaining to the examination of patent claims to medical uses.  Revisions were made to the guidelines issued in June of 2013, reported on here, in view of the recent Federal Court decision in AbbVie Biotechnology Ltd v Canada (Attorney General)(“AbbVie”), reported on here.  The notice provides some good news for patent applicants in the pharmaceutical area and indicates a possible softening of the Patent Office’s previous strict stance on the patentability of claims to medical uses that include a dosage regimen as an essential feature.

As mentioned above, the guidance document is directed to medical use claims, particularly those where an essential element of a claim is determined to include limitations on “how” a drug is to be used and those limitations include one or more ranges of values.  When such a determination is made then the Patent Office typically takes the position that the claim may cover a method of medical treatment, which is non-statutory subject matter in Canada. This position is based on Federal Court decisions that have held that inventions preventing physicians from exercising their skill and judgment in using a known drug for a known purpose are, in effect, methods of medical treatment.  While medical use claims directed to “what” is to be used for treating a condition are generally acceptable, assuming the conditions for novelty and inventiveness exist, problems can arise when an essential feature of the invention is “how” the medicament is to be used.

In the June 2013 guidance document, the Patent Office’s position was that claim limitations involving a dosing schedule or a range of potential dosages do not constitute patentable subject matter. Going further, this guidance document also specifically mentioned limitations based on “where” the treatment is to be administered and “who” is to receive the treatment as representing details of “how” to treat a patient.

Importantly, in view of the AbbVie decision, the Patent Office has backed away from their previous guidance document which extended the “how” of medical use claims to include all dosing schedules as well as “where” and “who” limitations. Therefore the revised guidance document specifies that the following are not considered to be essential elements that would be considered a method of medical treatment:

“a fixed dosage, a fixed dosage regimen, a patient sub-population or a particular administration site”

The revised guidance document also confirms that:

“[e]ssential elements that point to a limitation of a physician’s professional skill or judgment include those that provide details of a dosing schedule encompassing a range and those that represent a range of potential dosages that a patient may receive (as opposed to a range of dosage forms).”

The Patent Office’s position is in line with the claims that were held to be patentable subject matter by the Federal Court in AbbVie.  In fact, the Patent Office recently granted Canadian patent no 2,385,745, the patent application in dispute in AbbVie, and the allowed medical use claims contained a fixed dosage amount and fixed dosage regimen limitation as follows:

“A preloaded syringe comprising a syringe, 40 mg of an isolated human anti-TNFα-antibody wherein said antibody […] said preloaded syringe being (i) adapted for subcutaneous administration of its contents to the human subject in need thereof and (ii) for use on a continuous schedule having an every other week dosing interval of 14 days.”

This practice notice, and the granting of AbbVie’s patent, is welcome news.  However, the protection provided by a claim to a fixed dosage or a fixed dosage regimen remains narrower than protection provided by a claim to a broader range that can be obtained for such inventions in other major countries such as the United States and Europe.

The Canadian courts are currently considering further cases that involve the patent-eligibility of medical use claims containing dosage regimens.  In particular, the Federal Court of Appeal is expected to release a decision on the appeal of the decision of the Federal Court in Bayer Inc v Cobalt Pharmaceuticals Company. It will be interesting to see if this court will have anything new to say on this issue.