CIPO Reiterates Problem-Solution Approach in New Examination Practice Respecting Medical Uses

CIPO Reiterates Problem-Solution Approach in New Examination Practice Respecting Medical Uses

Effective June 10, 2013  PN2013-04

This Practice Notice builds upon the guidance in section 17.02.03 (Medical and surgical methods) of MOPOP and in PN 2013-02 (Examination Practice Respecting Purposive Construction).

MOPOP 17.02.03 can generally be relied on for guidance, however, the examination of medical use claims, including dosage regimens and dosage ranges, requires specific guidance.

The guidance in the present notice applies to a claim in the form “use of product X for treating disease Y” and may apply to claims such as “use of product X for the manufacture of a medicament for treating disease Y”, or “product X for treating disease Y…”, or a claim having similar language when construed to be a claim to the use per se.

Subject Matter

An assessment for section 2 compliance should be based on the essential elements of the claim as determined by a purposive construction.

The importance of a purposive construction approach is highlighted when assessing the patentability of claims that recite a dosage regimen or dosage range since the mere recitation of either of these does not necessarily mean the claim is non-statutory.

If, however, it is determined after a purposive construction 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, and thus, is not compliant with section 2 of the Patent Act.

Where 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.

Therefore, essential elements that point to a limitation of a physician’s professional skill or judgment include those that provide details of a dosing schedule, those that represent a range of potential dosages that a patient may receive (as distinct from a range of dosages forms), and those that narrow treatment to a patient sub-population (rather than bring treatment to a new population) or administration site.

Claim Analysis

To perform a purposive construction, an examiner identifies the problem the inventors set out to address and the solution disclosed.  This exercise generally must be performed considering the specification as a whole recognizing that the description guides the identification of the problem and solution.

  • Identifying the Problem
    • Should be guided by the examiner’s understanding of the common general knowledge in the art and by the teachings of the description.
    • Where the applicant is explicit as to the nature of the problem, examination should generally proceed accordingly unless doing so would be unreasonable on an informed reading of the application in light of the common general knowledge.
    • Examiner should consider what the inventors state about the background of the invention, their objectives (“objects of the invention”), any specific problems, needs, limitations or disadvantages known in the art or discovered by the inventors

 

  • Identifying the Solution
    • The solution is the element or set of elements essential to the successful resolution of the problem

Commentary

In our view there is some question about the propriety of CIPO mandating the use of a problem-solution approach. We do not see this approach enshrined in Catnic, Freeworld, or Whirlpool.

As a practical path forward, it is our view that the use of the problem solution approach may thus be a useful guideline, but that it is clearly not the only manner in which an analysis can be performed according to the Canadian Supreme Court; therefore, flexibility should be available to recognize the general principles of claim construction, and a rigid adherence to the problem-solution approach is not required under Canadian law.  We would therefore urge caution in being overly deferential to CIPO’s guidelines given that an overly rigid application of the problem-solution approach may lead to a result that is inconsistent with Canadian Supreme Court precedents.

In addition, CIPO’s language appears to conflate novelty and subject matter where it states “[i]f, however, it is determined after a purposive construction 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, and thus, is not compliant with section 2 of the Patent Act.” The implication appears to be that a claim with essential dosage elements can be found non-statutory if the other elements of the claim (e.g. the compound and the condition it is used to treat) are not new, but can be found statutory if the other elements are new. It is arguable whether dosage elements ought to be considered non-statutory; however, conflation of novelty and subject matter is likely not the optimal approach to resolving the issue.