PAB 1393, re Canadian Patent Application No. 2,544,223

It is difficult to obtain patent protection on an invention if its only described purpose is as an object of study. In this case, the Patent Appeal Board (“PAB”) found that Canadian Patent Application No. 2,544,223 (“the ‘223 Application’), entitled “Stabilized Alpha Helical Peptides and Uses Thereof” lacked utility, lacked sufficient disclosure, was obvious, and included indefinite claims. [6] However, the PAB concluded that if the Applicant cancelled all claims on file and replaced them with the Applicant’s proposed claims, this would overcome all defects in the application, putting it in allowable form.

Canadian Patent No. 2,544,223: Stabilized Alpha Helical Peptides and Uses Thereof

The ‘223 Application concerns certain polypeptides that have an alpha helical secondary structure stabilized through a cross-link. [24] These polypeptides are derived from a family of proteins that modulate apoptosis, also known as programmed cell death. [24] Sub-regions of these proteins, known as BH domains, are critical for apoptosis-modulating activity. [25] The claimed invention uses a technique known as hydrocarbon stapling to create stabilized alpha helical BH3 domains that are protected from degradative enzymes. [30]

The issues to be decided include utility, sufficiency of disclosure, obviousness, anticipation and claim definiteness. [6]

Utility: Lack of Sound Prediction

In the case at hand, the Applicant was relying on sound prediction to meet the requirement of utility. The doctrine of sound prediction, according to Apotex Inc. v. Wellcome Foundation Ltd., has three components: (1) there must be a factual basis for the prediction, (2) the inventor must have, at the date of the patent application, an articulable and “sound” line of reasoning from which the desired result can be inferred from the factual basis, and (3) there must be proper disclosure. [10]

The nature of the utility of the claimed invention was disputed. [35] While the Final Action stated that the polypeptides were useful as apoptosis modulators, the Applicant suggested they are useful to mimic or study polypeptides and may simply have the ability to penetrate cell membranes. [37] The PAB, however, found that while cell penetration would be seen as a beneficial property, the skilled person would not see that as a stand-alone utility common to all of the claimed subject-matter. [38] Further, the PAB stated that utility could not be satisfied merely by something being useful as an object of study, as that would reduce establishing a sound prediction of utility to a triviality. [39] It was concluded that the predicted utility was that the claimed polypeptides possess apoptosis modulating activity. [43]

The PAB found that, considering the common general knowledge and factual basis, the skilled person would not expect all of the claimed polypeptides to possess apoptotic-modulatory activity without explicit indication in the claim of a structural element responsible for the activity. [46] As numerous claims are not explicitly limited to apoptotic modulating polypeptides that have a structural element that confers apoptotic-modulatory activity, the utility of these claims were found to not be soundly predicted. [49]

Sufficiency of Disclosure: Specification Found to be Insufficient

Sufficiency of disclosure requires that a person skilled in the art, using only the specification, would be able to make the same successful use of the invention as the inventor at the time of the application, without having to display inventive ingenuity or undertake undue experimentation. [14] The PAB found that due to the nature of the generic chemical formula and failure to limit the scope of the claims, the skilled person would face extensive experimentation that would amount to an undue burden to achieve success. [53] As such, it was determined that the specification was insufficient. [54]

Obviousness: Claims Obvious to the Skilled Person

The claims in question for obviousness are independent claims that encompass cell membrane penetrating polypeptides. [56] Upon comparing these claims to the prior art, the PAB found that there was no inventive step in ascertaining that a peptide as disclosed in the prior art can penetrate a cell membrane, as its reference indicates an expectation of such a property. [63] While the Applicant noted that the peptides in the prior art do not exhibit apoptosis modulating activity, it was found to be irrelevant as the claims in question were not restricted to apoptosis modulators. [64] As such, these claims were found to be obvious.

Anticipation: Essential Element Not Disclosed in Prior Art

The PAB found that there was at least one essential element of each claim that was not disclosed in the prior art. [67] As such, the first prong of the anticipation test was not satisfied [68]

Claim Indefiniteness: Two Claims Lack Distinct and Explicit Terms

For a claim to avoid being deemed indefinite, its scope must be clear, precise and free from avoidable ambiguity or obscurity. [21] There were three sets of claims found to be indefinite in the Final Action. The first set of claims indicate that a variable alpha amino acid, defined as “Xaa”, is “the same amino acid as in an a-helix containing pro-apoptotic polypeptide”. [70] The PAB found that the skilled person would understand that other configurations, such as beta or gamma configurations, exist, and therefore would regard the phrase as a meaningful limitation and not indefinite.

The second set of claims include the expression “comprising a plurality of the polypeptide defined by…” The PAB found this set of claims to be definite, as when the full claims were read, the skilled person would not regard the language as ambiguous. [76]

The final set of claims include a general chemical formula with a variable defined as “Xaa”, however, the two claims in this set do not define in distinct and explicit terms what the variable can be. [79] The skilled person would be unclear on the scope of the claimed subject-matter, and therefore, these two claims were deemed indefinite. [80]

Proposed Claims Necessary for Compliance

The Applicant submitted proposed claims after the expiration of the time limit to respond to the Final Action. Upon review of these proposed claims, but without reproducing the proposed claims and making specific reference to each of the claim elements which were changed, the PAB found that they overcame all of the abovementioned defects in the application, putting it in allowable form. It was determined that the Applicant could cancel the claims on file and replace them with the proposed claims. If such amendments are not made within three months of this decision, the application will be refused.