Case: The New York Blood Center Inc. No. 2,308,623 (Re) (Patent Appeal Board)

Nature of case: Appeal of Final Rejection – section 30(6) Patent Rules

Successful party: New York Blood Center Inc.

Date of decision: March 8, 2012


Canadian jurisprudence on the patentability/validity of monoclonal antibody claims is relatively scant. However, the Commissioner of Patents, via the decisions of the Patent Appeal Board (“Board”), has recently offered specific guidelines on the subject. The latest decision on monoclonal antibody claims was rendered on March 8, 20121. The Board determined that some claims to methods of making antibodies and hybridoma cells that produce monoclonal antibodies against the Duffy blood antigen (especially the Fya and Fyb polymorphs) were found to be soundly predicted. No working examples of such methods were included in the application as filed. Further, claims directed to antibodies and hybridoma cells produced by the accepted method were also found to be sufficiently supported and enabled. The Board also suggested to include amendments to narrow the scope of some method claims to mirror more closely the experimental evidence (and the sound line of reasoning derived therefrom) presented in the application as filed.

In his originally-filed application, the Applicant has provided experimental results to the production of a mouse model for expressing the human polymorphs of the Duffy protein (a blood antigen) but failed to include data which show that it was possible to produce a monoclonal antibody using the mouse model. The claims to methods of producing a monoclonal antibody, to monoclonal antibodies as well as to hybridoma cells producing the antibodies were finally rejected for being broader in scope than the teaching of the description (lack of compliance with Section 84 of the Patent Rules as well as Subsection 27(3) of the Patent Act).

The Board firstly evaluated if the method claims go beyond the limits of a sound prediction given that the utility of the claimed methods had not been demonstrated as of the filing date since neither antibodies or hybridomas have been produced (compliance with Section 2 of the Patent Act). In view if the lack of exemplified embodiments, the Board evaluated the utility of the invention even if not explicitly stated in the Final Action.

The Board stated that, while the absence of the disclosure of even a single embodiment of the invention that actually worked is a relevant fact, it is not the sole consideration. The Board made clear that after-the-fact confirmation of the utility of an invention is not sufficient to support a predicted but not demonstrated utility. The fact that the claimed method has been successfully used after the filing date to produce antibodies was of no assistance in determining the soundness of the prediction at the filing date.

The Board indicated that since there is no indication in the specification of in the state of the art that suggests technical difficulties in producing the monoclonal antibodies with the mouse model, there was no undue experimentation or adaptation to obtain the claimed methods, antibodies and hybridoma cells (paragraph [45]). After reviewing the application, despite there being no examples directed to the claimed methods, and with the fact that no scientific rationale was provided that would weigh against the line of reasoning, the Board concluded that some of the method claims were soundly predicted to produce the antibody of interest and as such meet the utility requirement (paragraphs [46 and 47]).

Reassuringly, the Board also reviewed several recent Boards decisions regarding antibodies and, by applying the CSAHS test2, reaffirmed that working examples are not necessarily required for claims directed to unexemplified antibodies and hybridoma cell, particularly in this case where the antigen was adequately described and enabled.

In sum, this decision reaffirms the Board’s position that there is no absolute requirement for exemplary support in order to claim an antibody (especially a monoclonal antibody), method of producing an antibody or hybridoma cells. It further clarifies the Board position that a line of reasoning within an application supporting the utility of an invention should be presumed sound in the absence of contrary evidence, particularly in the absence of any scientific rationale to the contrary. This latest decision adds up the jurisprudence in Canada regarding biologics/biosimilars that is constituted by Patent Appeal Board decisions, which are not binding on the Court, in anticipation of a first round of judicial decisions in biosimilar litigation. To that effect, we are monitoring the first proceeding under the Patented Medicines (Notice of Compliance) Regulations commenced by Amgen against Teva Pharmaceutical Industries Ltd (Court File No. T-989-12).

Link to decision

The New York Blood Center Inc. No. 2,308,623 (Re) (Patent Appeal Board)