Predicted Utility: A Line of Reasoning is Presumed Sound Unless Proven Otherwise

Published June 13th, 2012

Commissioner’s Decision 1323

Summary – This decision deals with the Patent Appeal Board’s (“PAB”) review of the final rejection of Canadian Patent Application No. 2,308,623 (the “`623 Application”), to the New York Blood Center, Inc., directed to methods of making antibodies and hybridoma cells that produce antibodies.  The PAB found that several of the method claims in question were soundly predicted to have utility, based upon a fair reading of the teachings of the specification and a lack of evidence or scientific rationale to the contrary.  In addition, claims directed to monoclonal antibodies and hybridoma cells were found to be sufficiently supported and enabled despite a lack of exemplary evidence in the description.  In arriving at this decision, the PAB reiterated several key principles considered by the Canadian Courts in respect of sound prediction, support, and enablement.

Analysis –The antibodies produced by the methods and cells claimed in the `623 Application are capable of distinguishing between different polymorphic forms (Fya and Fyb) of the human Duffy protein, expressed naturally on the surface of red blood cells.  The method claims were rejected for lacking a sound prediction of utility and the product claims were rejected for lacking support in the description and for not being enabled.

First, the PAB cautioned that the disclosure requirement as it relates to sound prediction and as it relates to other aspects of proper disclosure should be assessed separately, citing paragraph [120] of Eli Lilly Canada Inc. v. Novopharm Limited, 2010 FCA 197.

Second, the PAB addressed the Examiner’s rejection of the method claims for lacking a sound prediction of utility.  While the Examiner conceded that the products produced by the claimed methods would themselves be expected to have utility, the Examiner questioned whether transgenic animals immunized as claimed would produce antibodies capable of distinguishing between the Fya and Fyb polymorphs.  This rejection was based solely upon the lack of examples in the disclosure establishing that a monoclonal antibody could be successfully produced using the claimed method.

In addressing this issue, the PAB restated the decision of the Supreme Court of Canada (“SCC”) in Apotex Inc. v. Wellcome Foundation Ltd., 2002 SCC 77, [2002] 4 S.C.R. 153 (“Apotex”) and made it clear that post-filing evidence of utility “is of no assistance in determining the soundness of the prediction at the filing date” [para. 22].  The PAB then considered the specification, construing the promise made and identifying the factual basis and sound line of reasoning set out therein.

Despite there being no examples directed to the claimed methods, the PAB found that at least some of the method claims would be predicted to have utility in view of the teachings of the description.  As the Examiner had not set out any evidence to the contrary or provided any scientific rationale that would weigh against the line of reasoning, as required by Apotex, the sound prediction rejection was reversed in part.

However, the PAB determined that certain teachings in the description indicated that aspects of the invention were critical to the predicted utility, namely the cell-surface expression of the polymorphic protein and the use of a murine cell when the transgenic animal is a mouse.  Therefore, the rejection of certain broader method claims was maintained as these claims did not require the presence of these allegedly critical aspects.

Third, the PAB addressed the Examiner’s rejections of the product claims for lacking support in the description and for not being enabled.  These rejections were primarily based upon the lack of exemplary support directed to monoclonal antibodies and hybridomas.  The PAB reviewed several recent PAB decisions regarding monoclonal antibodies and maintained that working examples are not necessarily required for claims directed to such technology.  It was found that the claimed invention was correctly and fully described and enabled and these rejections were therefore reversed.

Practice Point – While examples commensurate in scope with the claims of an application are the gold standard, there is no absolute requirement for exemplary support, even when sound prediction is being relied upon.  In addition, consistent with the SCC’s decision in Apotex, it appears to be the PAB’s position that a line of reasoning within an application supporting the utility of a claimed invention should be presumed sound in the absence of evidence or scientific rationale to the contrary.

Publication Archives
Contact us

Telephone: 416-595-1155
Fax: 416-595-1163


100 Simcoe Street
Suite 200
Toronto, Ontario, Canada
M5H 3G2