• Federal Court Requires Patent to Disclose the Factual Basis and Sound Line of Reasoning to Support a Sound Prediction of Utility of a Compound Claim
  • March 21, 2016 | Author: Urszula Wojtyra
  • Law Firm: Smart & Biggar/Fetherstonhaugh - Toronto Office
  • On January 15, 2016, the Federal Court dismissed Eli Lilly Canada Inc’s (Lilly) application for an order prohibiting the issuance of a notice of compliance (NOC) to Hospira Health Care Corporation (Hospira) for its generic version of pemetrexed disodium (Lilly’s ALIMTA): Eli Lilly Canada Inc v Hospira Health Care Corporation, 2016 FC 47. Pemetrexed is an antifolate drug useful in the treatment of certain cancers.

    The patent at issue, 1,340,794, was filed in 1989, and is an Old Act patent owned by Takeda and licensed to Lilly. The claims at issue were genus compound claims. The parties agreed that the inventive concept of the patent was the unexpected discovery that classical anti-folates bearing a particular 6/5 bicyclic ring system had anti-folate activity. It was known by 1989 that antifolates interfered with DNA replication and cell division.

    For reasons of judicial economy, the Federal Court only dealt with the single and determinative issue of sound prediction of utility, framed as “whether the person of skill in 1989 could have soundly predicted the promised utility of the untested compounds falling within Claims 7 and 9 from the test data reported in the Patent and from what was known in the art.”

    Promise of the patent: The Court first construed the promise of the patent, finding that the skilled person would construe the promise between the two positions advanced by the parties. Since the compound claims were silent as to the use, the person of skill must consider all of the language of the specification with a view to forming a purposive construction on the promise of the patent. Characterizing certain statements in the patent as clear and unambiguous language, the Court concluded that the patent promised the claimed novel compounds were useful as anti-tumour agents, and further this meant in vivo activity in relation to abnormal tissue.

    The Court, however, did not ascribe any weight to the subjective and qualitative references in the patent to “excellent” or “remarkable” activity, and distinguished between aspirational and hopeful language from explicit promises. Further, the Court held that the skilled person would not understand the patent as promising the compounds could be useful for treatment of tumours, or that they would have a relative advantage over known treatments, or toxicities specific to tumor cells. Statements in the patent to this effect were held by the Court to be in the nature of hopes or aspirations for some of the compounds, rather than promises for all of them.

    Disclosure of the factual basis and sound line of reasoning must be in the patent: The Court reviewed the legal principles associated with the law of sound prediction of utility. With regards to the element of disclosure, the Court stated “[i]n my view where utility is based on a sound prediction, there remains an obligation to disclose in the patent specification the factual basis and a sound line of reasoning supporting the prediction. That said, there is no requirement to disclose that which forms a part of the common general knowledge of the person of skill.” Regarding recent statements to the contrary,1 the Court stated:

    [46] Notwithstanding Justice Binnie’s remarks in Apotex Inc v Wellcome Foundation Ltd, quoted above, the issue of what the patentee must disclose to the public where utility is predicted remains somewhat controversial. In AstraZeneca v Apotex, 2014 FC 638, [2014] FCJ No 671, Justice Donald Rennie (as he then was), distinguished Apotex Inc v Wellcome Foundation Ltd, above, by limiting Justice Binnie’s remarks concerning disclosure to new use patents.

    [47] Justice Rennie also drew support from Justice Johanne Gauthier’s concurring, separate reasons in Sanofi-Aventis v Apotex, 2013 FCA 186, [2013] FCJ No 856, where she questioned the general requirement for a heightened level of disclosure in sound prediction cases. Justice Rennie dealt with Eurocopter, 2013 FCA 261, 116 C.P.R. (4th) 161, by describing the contrary view there expressed as both obiter and a less than robust endorsement of the need for heightened disclosure in sound prediction cases: see para 157.

    [48] While I have some sympathy for Justice Rennie’s and Justice Gauthier’s views, I am not persuaded that the state of the law on this issue has changed. In particular, it would take something more than Justice LeBel’s apparent reservations expressed in Pfizer v Novopharm, 2012 SCC 60 at paras 38-40, [2012] SCJ No 60, to displace the requirement for disclosure described by Justice Binnie in Apotex Inc v Wellcome Foundation Ltd, above, and, later, as clearly endorsed by the Federal Court of Appeal in Eli Lilly v Apotex, 2009 FCA 97 at paras 14-15, 78 CPR (4th) 388, in Eli Lilly v Novopharm, 2010 FCA 197 at para 83, [2012] 1 FCR 349 and in many decisions of this Court.

    Utility of all claimed compounds not soundly predicted from data in the patent: The vast majority of the compounds, including pemetrexed, claimed in the asserted claims had not been made or tested by Takeda before the filing date. Indeed, the patent disclosed the testing of four compounds, but the asserted claims claimed thousands of compounds.

    After considering the expert evidence of the parties, the Court favoured the evidence provided on behalf of Hospira that there were significant barriers to predicting anti-folate activity for an untested compound based on data for another. The Court noted Lilly’s evidence, in part presented “largely meaningless generalizations intended to avoid the evidence [from Hospira’s experts] about the inherent difficulties of predicting antifolate activity from one compound to another and across cell lines.” Therefore, the Court concluded that the skilled person would not have made a prediction of utility for the thousands of untested compounds included in the asserted claims, irrespective of whether the promise of the utility was as construed by the Court or as asserted by Lilly (some anti-folate activity in some cell line in vitro).



    1 The Court in Gilead Sciences, Inc v Idenix Pharmaceuticals, Inc, 2015 FC 1156, appeal pending, as previously reported, had adopted the below reasoning of Justice Rennie in AstraZeneca.