2,261,630 / infliximab / REMICADE / INFLECTRA
The 630 patent, held by Kennedy Trust, covers the adjunctive use of methotrexate [MTX] and infliximab for the treatment of rheumatoid arthritis [RA] in patients who do not respond fully to MTX alone. Infliximab is only approved for treatment of RA when used in combination with MTX [16]. Kennedy Trust’s licensee, Janssen, markets infliximab for use in combination with MTX under the name REMICADE [18]. Hospira’s infliximab product INFLECTRA, is a biosimilar of REMICADE, sold for the same purpose [18] (and see the product monograph). Hospira brought an action for a declaration that Kennedy’s 630 patent is invalid, and that INFLECTRA would not infringe, while Kennedy brought a counterclaim to the opposite effect [5].
MTX was a popular prior art treatment for severe RA [111], but for some patients — “incomplete responders” — MTX alone did not adequately control their RA. The efficacy of infliximab was also part of the cgk [113], but the duration of effect was limited [11]. It turned out that the combination of MTX and infliximab, as claimed in the 630 patent, exhibited enhanced efficacy over either drug alone as well as a sustained duration of effect [15]. On the facts, Phelan J concluded that this particular combination therapy was not obvious or obvious to try [230].
Hospira argued “an astonishing number and veritable panoply of patent law issues.” [24], including standing, ownership, improper priority, and double patenting plus along with the full range of the usual attacks, including anticipation, obviousness, sufficiency, utility, and overbreadth (and this list isn’t complete). As an academic, I hesitate to comment on litigation strategy, but I can’t help but feel that Hospira’s scattershot approach undermined the strength of its better arguments, particularly given that several of the arguments were thinly argued, occasionally without any supporting authority (see eg [159]). On overbreadth, Phelan J remarked that “Its submissions seem to have been made in the hope that something would “stick” – the patent law equivalent of the Hail Mary pass” [249]. At the end of the day, nothing stuck: Phelan J held the 630 patent to be valid and infringed. I won’t run through all of the arguments, but only those that raise a point of interest.
Experimental Use Exception to Anticipation
A couple of interesting points were raised by Hospira’s novelty attack. First, Phelan J endorsed the experimental use exception to anticipation, albeit in obiter [196]. Hospira argued that the patient consent forms used in Kennedy’s Phase II clinical trials were anticipatory. Phelan J rejected this primarily on the basis that confidentiality was established on the evidence (in part on the basis that the industry practice with clinical trials is to expect the maintenance of that confidence) [196i]. He also rejected it on public policy grounds, as it would effectively put an end to informed consent or to the patenting of medication [196i]. And he also suggested that “the experimental use exception is not as defunct as Hospira would have one conclude,” citing with approval Fothergill J’s decision in Bayer v Apotex 2016 FC 1013, discussed here (and see also Bayer v Apotex 2014 FC 436, Hughes J, discussed here). This experimental use defence to anticipation had some basis in the early case law, but it was not previously well-established; we now have three different Federal Court judges who have recently lent credence to the idea.
Speculative Anticipation
Hospira argued anticipation on the basis of a number of prior art documents which suggested trying infliximab or another anti-TNF-α antibody in combination with MTX, or referenced a trial in which that combination was being tried [196]. This is a bit of a twist on the usual anticipation attack, where the prior art says “We did X” and the question is whether X necessarily falls within the claims of the patent at issue. In this case (to oversimplify), the prior art says “Someone should try X” where X is exactly what the patent claims, namely combining MTX and infliximab to treat RA. (More precisely, the prior art references didn't all reference infliximab specifically.) Phelan J dismissed the prior art references as all being speculative [167], [191]. This calls to mind the case-law arising in the context of a conflict proceeding under the first-to-invent system, where in order to establish inventorship, it had to be shown that at the asserted date “the invention was no longer merely an idea that floated through the inventor's brain but had been reduced to a definite and practical shape” Ernest Scragg & Sons Ltd v Leesona Corp (1964), 45 CPR 1, 33. The allegedly anticipatory prior art in this case was really no more than “an idea that floated though the brain” of the proponents. It strikes me that just as a speculative idea cannot be an invention for the purposes of establishing priority over an inventor who had actually reduced the idea to practice, so it cannot be a disclosure sufficient to anticipate an invention that had actually reduced the idea to practice.
Blinding the Witness
Hospira’s experts were blinded. Phelan J gave little weight to this, saying “blinding alone is not a guarantee of reliability and it is not a sufficient reason to prefer the evidence of one witness over another” [203], consistently with 2016 FC 382 (discussed here). Phelan J also questioned whether blinding was even possible, at least on the facts of this case:
Further, given the involvement of the experts in this case in the development of RA
treatments during the relevant time period, it is at least questionable whether blinding
holds any value. It is impossible to believe that these experts were not aware of the
development of Remicade prior to this trial.
Methods of Medical Treatment
Hospira argued that the 630 patent was invalid as being an unpatentable method of medical treatment [136]-55]. Phelan J recognized that “[t]he jurisprudence with respect to the unpatentability of methods of medical treatment is not entirely consistent” [141]. This is not very surprising, given that the FCA has also called for “full consideration [of the patentability of methods of medical treatment] by this Court or the Supreme Court in a case where the issue is squarely raised on the facts” 2015 FCA 116 [101]. Phelan J’s observation further emphasizes the need for reform in this area of the law.
On the facts, Phelan J held that the patent at issue was not a method of medical treatment, essentially because “the use of X in combination with Y to treat disorder Z” is no different in substance from “the use of X to treat disorder Z” and the latter is clearly patentable: [147]. A claim of that type was at issue in Wellcome / AZT, 2002 SCC 77; and see the discussion here.
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