Fixed Dosage Regimen is Patentable Subject Matter

Janssen Inc v Pharmascience Inc 2022 FC 1218 Manson J

2,655,335 / paliperidone regimens / INVEGA SUSTENNA / NOC

In this action, Manson J found that Janssen’s 335 patent was not invalid for obviousness or as claiming an unpatentable method of medical treatment. The obviousness decision turned on the facts; the discussion of methods of medical treatment is of more general interest, though it does not break new ground.

This decision followed from Manson J’s prior decision in Janssen v Pharmascience 2022 FC 62, a motion for summary trial, in which he found that Pharmascience’s proposed paliperidone product would induce infringement of the 335 patent [48]: see here. The 335 patent has been the subject of a variety of other litigation, of which the most relevant is Teva Paliperidone 2020 FC 593, in which, as mentioned here, Manson J found that the 335 patent was not obvious, in a decision that turned on the facts.

Paliperidone is a second-generation anti-psychotic, known to be useful in treating schizophrenia. “[S]chizophrenia is incurable and requires life long management with antipsychotic medications. Adherence to a treatment regimen is critical. . . . A leading cause of relapse is non-adherence, where patients do no [sic] take their antipsychotic medication as prescribed, or at all” [11]. One strategy to improve adherence is the use of long-acting formulations. The 335 Patent relates to a long-acting formulation, in particular a dosing regimen for injectable paliperidone palmitate “depot” formulations, which releases from the injection site slowly [12].

Manson J’s analysis on obviousness followed similar lines to his decision in Teva Paliperidone 2020 FC 593: he found the same inventive concept [127] and his findings on the differences between the state of the art and the inventive concept were also consistent with Teva Paliperidone [134]. The key question was whether these differences were obvious. While Pharmascience argued that there were some crucial differences in the evidence on this point between this case and Teva Paliperidone [135], Manson J again concluded that the 335 patent was not obvious or obvious-to-try, in an analysis that turned on the facts [136]–[147]. The key point is that while there was a general motivation to develop a depot formulation of paliperidone to address compliance problems [155], there was not a specific motivation to develop the claimed dosing regimens [153]–[155]. Consequently, the claimed dosing regimens were not obvious [159].

The question of whether the 335 patent claimed unpatentable methods of medical treatment was of more general interest. Manson J noted that the Federal Court and FCA have acknowledged that the jurisprudence as to what constitutes an unpatentable method of medical treatment is inconsistent [161]. He noted, helpfully, “there appears to be no question in the case law that claims to a vendible product are patentable as not being methods of medical treatment” [163]. Many of the claims at issue were “product” claims, in particular claims to prefilled syringes (claims 1 to 16) and Swiss-type claims (claims 33 to 48), and consequently clearly do not constitute unpatentable methods of medical treatment [163]. It is worth noting that Manson J expressly stated that the Swiss-type claims are “product” claims [109]; his holding in Hoffmann-La Roche v Sandoz 2021 FC 384, [95]–[109], that the Swiss-type claims should be construed as use claims now appears to be an outlier: see also my recent post on Janssen v Apotex 2022 FC 996.

The question therefore only arose in respect of the “use” claims: [163]. The justification for the bar on patenting methods of medical treatment is that claims to a method of medical treatment should not constrain a medical professional in the exercise of their skill and judgment: [166], quoting Hospira 2020 FCA 30 [52]. Manson J summarized the law as being that use claims to dosing regimens that are “restricted to particular dosages and specific administration schedules” have been found to be patentable subject matter, “whereas claims to dosages or schedules with ranges within which the physician must exercise skill and judgment have been found to not be a vendible product and thus not patentable” [164]. This is a point Manson J has made before, in Hoffmann-La Roche v Sandoz 2021 FC 384. As discussed here, I’m not sure that distinction entirely reconciles the cases; and Manson J immediately went on to note that claims involving dosage ranges have been held unpatentable “at least in some cases” [165]. Moreover, Manson J evidently does not consider the distinction to be sound in principle, saying the distinction “seems to have a questionable underpinning in resulting judgments based on this dichotomy” but “nevertheless that is where we are under the current state of decisions up to and including decisions in the Federal Court of Appeal” [165]. In other words, we can all recognize that the current state of the jurisprudence is unsatisfactory, but it is what it is, at least for now.

Despite the very confused state of the law, this turned out to be a relatively easy case. The use claims were to a very specific dosing regimen, with “no choices in respect of possible ranges for the dosage amounts, which are fixed at loading doses of 150 mg-eq. on Day 1, 100 mg-eq. on Day 8, and 75 mg-eq thereafter as the maintenance dose” [168]. These are the types of claims that have consistently been held to be patentable subject-matter. Manson J noted that while there was some flexibility in dosing windows, “those choices do not have clinical implications,” as they were incorporated into the regimen to allow for a missed dose, or for convenience in the injection site [170].

Manson J made two observations of general interest. First, as the FCA pointed out in Hospira [52], quoted at [166], “It would seem that a medical professional will be constrained in their exercise of skill” whether the patent claims a fixed dosage or a range of dosages. That is, if a medical professional decides, in their professional judgment, that a certain dosage is required, and that dosage is claimed in a claim to a fixed dosage, their skill will be constrained as much as if it fell within a claimed range. Manson J noted that, in this case, the use claims “do not prevent physicians from practicing in a manner they had previously ‘because they weren’t doing anything before’ the 335 Patent with paliperidone palmitate to treat schizophrenia” [167]. Note the shift from asking whether the medical professional is constrained in the exercise of their skill and judgment, to asking whether they are constrained from practising in the manner they had previously. It seems to me that the medical professional will never be prevented from practising in the manner that they had previously in any case in which the claim is not invalid for anticipation. A valid patent does not constrain a physician’s choices as compared with what they were doing previously; on the contrary, it expands their choices by disclosing new information about how to best treat patients, which would not have been available but for the lure of the patent.

Manson J also noted that “A physician can choose to implement a claimed specific dosing regimen or not; however, skill and judgment are not required to implement the claimed dosing regimens” [171], and for that reason, the claimed subject-matter was not an unpatentable method of medical treatment. This observation also illustrates that the exercise of skill and judgment is always required in medical treatment, even in the administration of a fixed dosage regime. If the exercise of skill and judgment in deciding whether a particular regime is appropriate is not objectionable, I have difficulty seeing why it is any more objectionable if some skill and judgment must be exercised in deciding the exact dose within a claimed range.

ONCA Affirms that PM(NOC) Statutory Stay Damages Regime is a Complete Code

Apotex Inc v Eli Lilly Canada Inc 2022 ONCA 587 affg Apotex v Eli Lilly 2021 ONSC 1588

2,041,113 / olanzapine / ZYPREXA

Under the patent linkage system established by the PM(NOC) Regulations, a patent that is ultimately held to be invalid can keep competitors off the market for two years by operation of the statutory stay pursuant to s 7(1)(d). If the generic prevails, s 8 provides a remedy in the form of damages for the losses suffered from having been kept off the market by the statutory stay. One well-established limitation to s 8 damages is that if the generic is unsuccessful in the NOC proceeding, it cannot claim s 8 damages, even if the patent is subsequently held invalid in an infringement action: 2013 FCA 282 (here). So, Lilly had prevailed in NOC proceedings against Apotex based on the 113 patent (2007 FC 455 affd 2008 FCA 44), but that patent was subsequently declared invalid in separate proceedings (2011 FC 1288 affd 2012 FCA 232). Because Apotex lost in the NOC proceedings, it was not entitled to s 8 damages. In this action, Apotex sought to recover damages for having been kept off the market on the basis of three other causes of action: breach of the Ontario Statute of Monopolies; s 7(a) of the Trademarks Act; and common law conspiracy in restraint of trade [34]–[36]. As discussed here, Schabas J, at first instance, dismissed the action on a motion for summary judgment, holding that none of these causes of action raised a genuine issue for trial. The ONCA has now affirmed, essentially holding that Schabas J was correct on all points. I won’t go through the decision in detail. Instead, I’ll summarize and point out some highlights.

The first point is that the NOC Regulations are a “complete code.” Well, they’re not actually a complete code, as Apotex pointed out [36], but the real point of Schabas J’s decision is that the Regulations are “a complete code” for the purposes of determining whether damages were available to Apotex for having been kept off the market as a result of the operation of the Regulations; and for that purpose, they are a complete code [37], [39].

Second, Schabas J held that Lilly cannot be made liable for exercising its statutory rights [ONSC 113]–[118]. The ONCA agreed:

[42] Eli Lilly is not liable for actions that it was authorized by law to take and for harms that were caused by the operation of the patent regime that Apotex invoked. Absent abuse of process, which was not alleged or found here, Eli Lilly was entitled to pursue the legal process provided for under the PM(NOC) Regulations.

This is probably the most significant general holding of law in this decision. As I noted in my post on Schabas J’s decision, it is broadly similar to the US Noerr–Pennington doctrine. The Noerr–Pennington doctrine has found application in a variety of contexts in US law: see Gugliuzza, Patent Trolls and Preemption, (2015) 101 Va L Rev 1579, 1611–12. It will be interesting to see if this holding takes on a life of its own in the Canadian context.

The Statute of Monopolies point turned on Apotex’s argument that the Statute of Monopolies only exempts valid patents from actions for damages [44]. But, on its face, the Statute “does not distinguish between valid and subsequently invalidated patents” [47]. The ONCA further explained that:

Parliament passed the Statute of Monopolies in an attempt to limit abuses by the Crown in granting “letters patent”, not “patents of invention”. The Statute was passed in response to the Crown granting letters patent to operate or regulate industries, or to have others act as agents of the Crown in operating monopolies for trade and industry, independent of merit or invention.

The ONCA did not cite any authorities on this point. It is more confident than I might be as to the purpose of the Statute, and of course patents of invention are, or at least were at the time, letters patent, so that distinction is a bit strained. But that doesn’t really make any difference given the basic point that the Statute does not distinguish between valid and invalid patents.

The Trademark claim turned on the notion that Form IV filed by Lilly to list the 113 patent on the register was misleading because the 113 patent was invalid. However, all statements made by Lilly were true at the time it made them [51].

The conspiracy claim was struck because Lilly committed no unlawful acts; Lilly was entitled to seek and obtain a patent and list it on the Register: [53].

The ONCA also affirmed a very substantial cost award in Lilly’s favour on a deferential standard of review, after taking the opportunity to review the relevant principles of costs awards. The discussion might be useful to lawyers more familiar with Federal Court practice who are involved in litigation in the Ontario courts.

Obscure Prior Art Less Likely to be Combined

Google LLC v Sonos, Inc 2022 FC 1116 Zinn J

            2,545,150 / Adaptive Echo and Noise Control

This brief decision is notable for providing further clarification of how obscure prior art is to be treated in the context of an obviousness attack.

Various “virtual assistants” such as Alexa or Google Assistant, respond to voice commands that may be picked up by a range of smart appliances, such as Sonos’s well-known home audio speakers. Google’s 150 patent relates to a system of echo cancellation and noise suppression in which the order of echo cancellation and noise suppression is adaptively determined based on an amount of noise in the received signal [86]. Google brought this action alleging that Sonos’s smart speakers infringed. In defence, Sonos disputed infringement and alleged invalidity based on obviousness.

As is often the case, much turned on claim construction. A preliminary issue was whether recourse to the disclosure is always permitted or is permitted only when the claims are ambiguous. Biogen v Pharmascience 2022 FCA 143, released only a week before, settled that recourse to the disclosure is always permitted. While Zinn J would not have had the benefit of Biogen v Pharmascience, he nonetheless came to a consistent conclusion after reviewing the recent FC caselaw [42]–[44].

A key point on the facts was whether “echo cancellation” is a subset of “noise suppression” or whether the two are mutually exclusive [47]. Zinn J concluded that the two were distinct, in an analysis that turned primarily on a purposive reading of the patent as a whole, rather than on the expert evidence: see [50], noting that the two must be distinct to give meaning to Claim 7; and [51], noting that the two are treated as distinct throughout the disclosure. Zinn J’s construction of other contentious claim elements turned largely on the expert evidence.

Zinn J held that Sonos did not directly infringe because the allegedly infringing features were disabled on delivery [65], so that infringement could only be established by inducement. But he also had no difficulty in concluding that if the user infringes, that infringement will have been induced by Sonos [67]–[69], so infringement simply reduced to whether the user would infringe [70]. He answered this question in the negative, in an analysis that turned entirely on the evidence [81].

The obviousness inquiry was originally taken to be an essentially factual inquiry as to whether the invention would have been obvious to a person skilled in the relevant art. From this, it follows directly that the state of the art relevant to an obviousness attack does not comprise the entire body of publicly available information, but only that information which would actually be available to the skilled person. When the non-obviousness requirement was codified in s 28.3, it provided that obviousness is to be assessed in light of information disclosed “in such a manner that the information became available to the public in Canada or elsewhere.” On its face, this states that the entire body of public information constitutes the state of the art. The question then was whether codification was intended to change the law on this point, and if so, what the specific effect of the change was. In Hospira 2020 FCA 30, discussed here, the FCA held that “it is an error to exclude from consideration prior art that was available to the public at the relevant date simply because it would not have been located in a reasonably diligent search” but at the same time “The likelihood that a prior art reference would not have been located by a [person skilled in the art] may be relevant to consideration of step 4 of the obviousness analysis (whether differences between the state of the art and the inventive concept constitute steps which would have been obvious to the PSA) in that the uninventive PSA might not have thought to combine that prior art reference with other prior art to make the claimed invention” [86]. As I noted in my post on Hospira, this suggests that there can be no mosaicing of prior art that is not available in a reasonably diligent search. However, the FCA’s comments in Hospira were brief, as the Court remanded the issue for reconsideration.

The issue of obscure prior art arose in this case because a key element of prior art was the US patent 5,668,871. The 871 patent was very clearly obscure prior art—which is to say, prior art that would not have been found in a reasonably diligent search; it was not known to either expert prior to the litigation, nor was it found by either expert during their preparation, “despite their personal familiarity with the field and despite [Sonos’s expert] having conducted a diligent search” [92].

Google argued that the 871 patent was not eligible prior art for the purposes of the obviousness attack for that reason. Zinn J rejected this argument on the clear authority of the above-quoted paragraph 86 of Hospira [96].

The question then is how the obscure prior art may be used. Zinn J pointed out that “the difficulty of locating a document is a matter that may be considered at the final step,” relying on the same passage from Hospira [97].

[98] The question thus becomes whether, given the obscure nature of the 871 Patent, the uninventive POSITA might have thought to combine the 871 Patent with other prior art to make the claimed invention.

On the facts, Zinn J held that “given the difficulty in locating the 871 Patent, that the POSITA would not have been led directly and without difficulty to combine these references” [105], and he consequently rejected Sonos’ argument that the 150 Patent was obvious based on “any combination involving the 871 Patent” [106]. I must say that it is not clear to me exactly which references in addition to the 871 patent Zinn J was referring to as “these references” but I take it the other references were part of the prior art, but not part of the common general knowledge.

Google had relied on Kane J’s statement in Teva v Pharmascience 2020 FC 1158 [796], to the effect that “the prior art relied on by Pharmascience would not all have been found by the POSITA,” affd 2022 FCA 2 (Locke JA) [32] noting that Kane J “was apparently concerned that, given the difficulty in locating certain prior art, the PSA would not have been led directly and without difficulty to combine these references.” Zinn J considered that Locke JA was not contradicting his own prior statement in Hospira but was simply saying that “the difficulty of locating a document is a matter that may be considered at the final step” [97]. I think this is right, considering Kane J’s statement at [801] that “I agree with Teva that Pharmascience has not explained how or why the POSITA would regard these pieces of prior art together in a mosaic to lead to the invention,” and moreover “even if the POSITA was handed this mosaic, it does not lead them directly to the subject matter of the claims.” So, I don’t see any inconsistency.

Zinn J’s decision is consistent with Fothergill J’s decision in dTechs 2021 FC 190 (see here). However, it is possible that it diverges from Manson J’s decision in Biogen v Taro 2020 FC 621; in my post on Manson J’s decision I suggested that his analysis was notable for making a mosaic of obscure prior art. Manson J’s decision holding the patent at issue invalid for obviousness was just affirmed by the FCA in Biogen v Pharmascience 2022 FCA 143 [143]–[171]. However, the FCA decision did not address this issue; the main ground of appeal was that Manson J had failed to adopt the mantle of the POSITA, essentially by failing to recognize that the skilled person in the field would be highly skeptical of any new alternative treatments that were not supported by double-blind, placebo-controlled trials [144], [148]. So far as I can see, the issue of mosaicing of obscure prior art was simply not addressed at all. I think the most likely explanation is that I was simply wrong in thinking that the prior art relied on by Manson J was obscure prior art, which would explain why the issue was not raised on appeal. In that case, there is in fact no divergence between these decisions on this issue. In any event, even if Manson J did combine obscure prior art, the fact that the FCA affirmed on obviousness cannot be taken as holding that it is permissible to combine obscure prior art, given that the issue was not discussed. If the FCA had intended any comment on that point, it would surely have discussed Hospira.

The Whole Disclosure Must be Reviewed

Biogen Canada Inc v Pharmascience Inc 2022 FCA 143 Gauthier JA: Gleason, Rivoalen JJA affg Biogen Canada Inc v Taro Pharmaceuticals Inc 2020 FC 621 Manson J

            2,562,277 / fampidrine / FAMPYRA / NOC action

            FC Mosaic FC Anticipation FC Medical Treatment

There has been an on-going debate in the case law as to whether recourse to the disclosure is always permissible in claim construction, or is permissible only if the claim terms are ambiguous. In this decision, Gauthier JA has given us a clear and definitive answer (my emphasis):

[73] [T]he point of the [claim construction] analysis is to interpret and respect the inventors’ objective intention as manifested in the words he used. This is why the whole disclosure must be reviewed, even for words that would appear at first glance to be simple and unambiguous when reading only the claims. Indeed, one of the reasons for reviewing the disclosure is to determine whether the inventor actually defines particular words that could appear plain and simple even to a POSITA when reading only the claims.

Gauthier JA again emphasized the point

[71] Although the principles described by the Federal Court are not in dispute in this case, it is still important to reiterate that a patent’s description (also referred to as the disclosure) must be considered when construing claims.

And see [72] stating that “[p]urposive claim construction involves looking at words of the claims in context,” and the relevant context includes the description.

Moreover, Gauthier JA directly applied this principle in her analysis. The specific question was whether terms such as “for improving walking” incorporated a subjective assessment by the patient, or only a quantitatively measured improvement, as Manson J held [75]. While the FCA ultimately upheld Manson J’s claim construction on a deferential standard of review [142], this is not a case where the FCA affirmed the FC claim construction on a holistic appreciation and a deferential standard, perhaps glossing over some details. One of the appellant’s main arguments was that Manson J erred in construing certain contentious terms against what they considered to be conclusive evidence of agreement between the experts [77]. Gauthier JA consequently chose to go into considerable detail on claim construction to illustrate why it can be appropriate for a trial judge to reject expert evidence of how a skilled person would read a claim when that evidence is not supported by a proper application of the principles of purposive claim construction [86], [91]. (This case is also an excellent illustration of the principle that claim construction is a matter for the court.) Consequently, much of Gauthier JA’s discussion reflects the FCA’s own view as to the correct claim construction, not simply the application of a deferential standard of review.

Gauthier JA pointed out that the 277 patent expressly stated that all technical and scientific terms used have the same meanings as commonly understood by one of ordinary skill in the art, “[u]nless defined otherwise,” and indeed, certain specific expressions were given specific definitions [96]. Thus, Gauthier JA’s observation that one must review the disclosure “to determine whether the inventor actually defines particular words that could appear plain and simple” when reading only the claims was directly illustrated in this case. Similarly, she also noted the key contentious terms, namely “use for improving”, “use for increasing” or “use for reducing,” were common words that “[o]n their face . . . appear plain and simple” [82]. She nonetheless went on to consider the description at length [87]–[116], before reviewing the expert evidence and finally arriving at a conclusion on claim construction [142].

It is somewhat unfortunate that Gauthier JA did not refer to the debate over this point, but she cannot have been unaware of it. And this is not a situation where there was some clear and unambiguous statement from the FCA to the effect that recourse to the disclosure is impermissible unless the claim terms are ambiguous; rather, the debate has arisen because of a variety of ambiguous statements by the FCA: McHaffie J provided a thorough review of the cases in Guest Tek 2021 FC 276, discussed here. The point was also raised in Google v Sonos 2022 FC 1116 [40], released just a week after this decision. In that case, Zinn J reviewed the recent FC caselaw and agreed with McHaffie J that “[t]he exercise of construction must consider both the disclosure and the claims” [42]–[44]. Thus, there was already a consensus emerging at the FC level, which is consistent with the position stated by Gauthier JA. The key point is that recourse to the disclosure is always permissible, but “[t]he disclosure should not be used to enlarge or contract the scope of the claims, particularly through the addition of words or limitations not found in the claims” [42], quoting and agreeing with Guest Tek [47]. In the circumstances, I take it that Gauthier JA did not review the caselaw because she was of the view that the point was not sufficiently controversial to warrant it. In any event, given the very clear statement of principle, combined with its application to the facts, we can now take it as settled law that in carrying out claim construction, “the whole disclosure must be reviewed, even for words that would appear at first glance to be simple and unambiguous when reading only the claims.”

Obviousness

After affirmed Manson J’s holding on claim construction, the FCA went on to affirm on his finding that the asserted claims were invalid for obviousness [170]. In my post on Manson J’s decision on this issue, I suggested that his analysis was notable for making a mosaic of obscure prior art. This issue was not raised at the FCA. I’ll discuss it further in my upcoming post on Google v Sonos 2022 FC 1116, which raises the same issue.

Anticipation

Manson J also held the 277 patent invalid for anticipation, noting that the key anticipatory prior art “is similar to the allegedly anticipatory art in Hospira [2020 FCA 30]” [133]. As discussed here, I had several concerns regarding the implications of Hospira, as reflected in Manson J’s analysis. It is therefore noteworthy that Gauthier JA declined to address anticipation:

[172] As mentioned, there is no need to discuss the Federal Court’s findings in respect of anticipation, nor is this the proper case to address in obiter the question of how Hospira Healthcare Corporation v Kennedy Trust for Rheumatology Research, 2020 FCA 30 (Hospira) and the Federal Court’s conclusion on anticipation might have an impact on inventions requiring investments in large clinical trials, as briefly argued.

[173] That said, it is important to recall that nothing in these reasons or my conclusion that the appeal should be dismissed, should be understood as endorsing the conclusion of the Federal Court on anticipation. Also, neither this Court in Hospira nor the Federal Court intended to modify the well-established test enunciated in Sanofi (FC Decision at paras. 114-115).

Nor did Gauthier JA discuss Manson J’s holding that none of the asserted claims were invalid as covering unpatentable methods of medical treatment [FC 214], discussed here, as the issue was not raised before the FCA [33].

What Is the Date for Assessing Sufficiency?

Pharmascience Inc v Bristol-Myers Squibb Canada Co 2022 FCA 142 Locke JA: de Montigny, Monaghan JJA affg 2021 FC 1 Zinn J FC Selection

2,461,202 / 2,791,171 / apixaban / ELIQUIS

My previous post addressed issues of selection patents raised by this decision. This post discusses the insufficiency attack on the 202 patent, and concludes with a brief discussion of the 171 patent, which reveals another failed attempt to give independent effect to overbreadth as a ground of attack. As described in my last post, the patents in suit relate to the anticoagulant compound apixaban which is used in treating thromboembolic disorders, including stroke. The 202 patent claims the compound apixaban as such, as well as its use in the treatment of thromboembolic disorders [4]. The 171 patent claims various formulations of apixaban. Only validity was at issue.

Insufficiency attack on the 202 patent

Pharmascience argued that the 202 patent was invalid for insufficiency because it did not indicate that the focus of the invention was apixaban at either the filing date or the publication date [22]. Apixaban was merely one of hundreds of examples, and the claims focusing on it were not introduced until shortly before the patent issued [22].

The answer to this argument is that it is the validity of the granted patent that must be considered. Saying that validity on one ground or the other is assessed as of a particular date does not change that. So, when we say that the claims must be novel as of the claim date, we do not mean that the claims as they existed at that date must be novel, but rather that the claims in the granted patent must claim subject-matter that was novel as of the claim date [31]. The same applies to sufficiency: it is the specification of the issued patent that must adequately disclose the invention [32]–[33]. If we say that sufficiency is assessed as of the filing date (of which, more below), that means that the specification as granted must enable a person skilled in art to make the invention in light of their common general knowledge as of the filing date.

Consequently, this point should have been framed as an added matter objection: “[t]he real debate here should be whether the addition of claims specific to apixaban introduced new matter to the specification of the 202 Patent that could not reasonably be inferred from the application as filed” [37]. It was problematic to raise this on appeal without having raised it at trial [37], but in any event, Locke JA noted that an added matter objection probably could not be sustained, as apixaban was specifically described in Example 18 and that would seem sufficient to support the introduction of claims thereto [37].

That all makes sense. But the decision also has a relatively lengthy discussion of the appropriate date for assessing sufficiency. Pharmascience relied on the decision of Hughes J in Zoledronate 2013 FC 283 [179]–[188], which implied that the correct date is the publication date [23]. Locke JA discounted the Zoledronate decision for various reasons (eg the discussion was obiter), without actually saying it was wrong and without specifically stating the law as to the appropriate date for assessing sufficiency [26]–[28]. For example, Locke JA noted that Hughes J did not address the view expressed by MacKay J in Merck v Apotex 59 CPR(3d) 133 (FCTD) that the date of issue is the appropriate date for assessing insufficiency [28], but only by way of indicating that Hughes J’s analysis was incomplete.

This seems a bit strange because, as indicated in my post on Zinn J’s decision, I thought the point was settled in Idenix v Gilead 2017 FCA 161 [46] affg 2015 FC 1156. In that case, the patentee, Idenix, had not actually synthesized any of the claimed compound as of the filing date: see here. Gilead, therefore, made a classic “how to make” insufficiency argument, and Annis J held that the disclosure was not sufficient to allow a skilled person to synthesize the compounds, and held the patent invalid for that reason. This was even though, by the time of trial, the claimed compound could be synthesized by three different pathways [FCA 46]. I’ve taken a look through Annis J’s (very long) decision, and it is not clear to me what date he took to be the appropriate date; the focus of the discussion is on showing that “retrosynthetic analysis”, based on the specification plus routine experimentation, was not sufficient to enable a skilled person to make the claimed compounds. The first public disclosure of how to make the compounds was in January 2005 [FC 501], so the patent would have been sufficient as of that date, at least if the skilled person were taken to be aware of that public disclosure. The 191 patent at issue had a filing date of June 2003 and a publication date of January 2004, so the patent would have been insufficient as of those dates, but sufficient as of the date of issue. This implies that we can at least rule out the date of issue as the appropriate date for assessing sufficiency.

The FCA affirmed the finding of insufficiency saying:

[46] Though reversed on other points, this Court held in [Viagra] 2010 FCA 242 at paragraph 79. . . that courts must “determine whether the disclosure was sufficient as of the date of filing. As a result, anything which occurred subsequent thereto is of no relevance.” In my view, Idenix’s argument reflects the benefit of hindsight rather than the knowledge of the skilled person at the relevant date.

This clearly indicates that the appropriate date is the filing date, though the result is consistent with using the publication date.

I find it peculiar that, in this case, Locke JA did not mention the FCA decisions in either Idenix or Viagra. It is true that neither of those cases analyzes the issue—the statements of the appropriate date are conclusory—while the FC decisions of MacKay J Merck v Apotex and Hughes J in Zoledronate do have an extended discussion. But still, the express statements by the FCA are directly on point, even if not fully reasoned.

I suspect Locke JA chose to avoid Idenix or Viagra because their endorsement of the filing date sits uneasily with his response to Pharmascience’s argument:

[33] [Pharmascience] notes that subsection 27(3) identifies the requirements of the “specification”, and argues that subsection 27(2) indicates that it is the specification as filed that must meet those requirements. However, such an argument does not withstand scrutiny. Firstly, it would effectively read out subsection 27(6), which contemplates amendments to bring the application into compliance with the sufficiency requirements. Secondly, a similar argument would seem to apply to the requirements for novelty (the opposite of anticipation) and inventiveness (the opposite of obviousness). Sections 28.2 and 28.3, which address these issues, both refer to requirements for “[t]he subject-matter defined by a claim in an application for a patent.” PMS’s focus on the specification as filed for determining sufficiency would also imply a focus on the claims as filed for anticipation and obviousness, since the relevant provisions mention “a claim in an application”. I can see no reason that the approach that PMS urges for sufficiency would not apply similarly to anticipation and obviousness.

I’ll take the second point first. It is perfectly clear that novelty and inventiveness are assessed as of the claim date. But it is the claims as granted that must have been new and inventive as of the claim date; there is no requirement that the claims as they existed as of the claim date must be new and inventive. The same point applies to sufficiency. The specification as granted (including any amendments as per 27(6)) must have been sufficient at the relevant time (whenever that is). That means that in assessing the sufficiency of the specification as granted, we must consider whether it would have allowed the skilled person to practice the invention at the relevant date, without the assistance of new techniques or knowledge that emerged after that date. Turning to the first point, saying that the relevant date for sufficiency is the filing date does not read out 27(6). To say that the relevant date is the filing date does not mean that it is the specification as it existed as of that date that must be sufficient, just as saying that the relevant date for utility is the filing date does not mean that it is the claims as they existed at that date that must claim useful subject-matter. It simply means that in assessing the sufficiency of the specification as granted, common general knowledge arising after the filing date cannot be taken into account. (I note also that while 27(6) permits amendments, that is subject to 38.2, which only permits the addition of matter that can reasonably be inferred from the specification as filed. Consequently, I suspect it would be difficult, and perhaps impossible, to amend a specification that is insufficient as of the filing date so as to render it sufficient at some subsequent date. But that is an aside.) So, the fact that claims can change post-filing does not mean that the relevant date for assessing novelty is post-filing; similarly, the fact that the specification may be amended post-filing does not mean that the relevant date for assessing sufficiency is not the filing date.

At the end of the day, I’m inclined to think that the appropriate date for assessing sufficiency is indeed the filing date. But I suppose the fact that the FCA in this case ignored Idenix and Viagra means that the point should now be considered open.

171 patent

The 171 patent relates to a formulation of apixaban with, inter alia, a specified particular size. Locke JA affirmed Zinn J’s holding on the facts that it was not obvious-to-try [39]–[59]. Pharmascience also argued that the patent was invalid for ambiguity on the basis that the method for determining particle size was not specified, and different methods could give different results. Locke JA dismissed this argument, pointing out that the specification did describe a particular measuring method and a skilled person would understand this to be the method to use [66].

Finally, Pharmascience made an overbreadth attack. In Seedlings 2021 FCA 154 (blogged here) the FCA affirmed that “overbreadth remains a proper ground of invalidity” [50]. Consequently, we are now seeing overbreadth raised regularly as a ground of invalidity. But parties attacking the validity of a patent have struggled to find an approach to overbreadth which gives it any independent force. This case is another example. Locke JA remarked that “The nature of [Pharmascience’s] argument on overbreadth of the 171 Patent is not entirely clear” [69]—which is not entirely surprising, given that the concept of overbreadth itself is not clear. In any event, Locke JA’s discussion was brief, so I’ll just note that Locke JA, after dismissing it on the facts, indicated that the attack “would seem to relate to the sufficiency of the 171 Patent, rather than overbreadth” [71]. Another attempt to give some effect to overbreadth as an independent ground of invalidity has failed.

UPDATE: see my follow-up post on the date for assessing sufficiency.

Is it Necessary to Disclose the Special Advantage of a Selection Patent?

Pharmascience Inc v Bristol-Myers Squibb Canada Co 2022 FCA 142 Locke JA: de Montigny, Monaghan JJA affg 2021 FC 1 Zinn J FC Selection

2,461,202 / 2,791,171 / apixaban / ELIQUIS

This decision raises some issues related to selection patents and the date for assessing sufficiency. I’ll deal with these in separate posts, starting with selection patents.

The patents in suit relate to the anticoagulant compound apixaban which is used in treating thromboembolic disorders, including stroke. The 202 patent claims the compound apixaban as such, as well as its use in the treatment of thromboembolic disorders [4]. The 171 patent claims various formulations of apixaban. Only validity was at issue. Four related actions, two each involving Pharmascience and Sandoz as defendants, were tried “on a coordinated basis” at first instance. Only Pharmascience pursued its appeal [1].

The more interesting issues relate to the 202 patent and its validity over the prior art patent 2,349,330. Apixaban is a selective inhibitor of the enzyme Factor Xa (FXa) and it works by blocking certain clotting proteins in the blood. The 330 patent disclosed and claimed a large class of compounds which were disclosed as FXa inhibitors and so potentially useful in the treatment and prevention of thromboembolic disorders [FC 79]. The class is extremely large: “more possibilities than stars in the universe” [FC 80]. On the evidence provided by Sandoz’s experts, the class encompassed apixaban [FC 77], but did not specifically disclose it, or describe how to make it [FC 82]. Thus, the 202 patent is what would traditionally be called a selection patent over the 330 patent. A three-part test for the validity of selection patents was set out in IG Farbenindustrie (1930) 47 RPC 289 (Ch) 322-23 and endorsed in Sanofi 2008 SCC 61 [9]-[11]. The factors, in summary, are: (1) a valid selection must possess some substantive advantage over the genus; (2) all of the selected members must possess the advantage; (3) the advantage must be peculiar to the selected group.

There has been considerable debate as to the role of the IG Farbenindustrie factors and their relationship to the standard grounds of invalidity. In Olanzapine 2010 FCA 197 [33] the FCA stated that an assessment of whether the IG Farbenindustrie conditions have been met “does not constitute an independent basis upon which to attack the validity of a patent,” and “A selection patent is the same as any other patent. Its validity is vulnerable to attack on any of the grounds set out in the Act.” This implies that the IG Farbenindustrie factors are a reflection of one or more of the standard grounds of invalidity. As discussed in my post on Zinn J’s decision, he was quite skeptical of the IG Farbenindustrie factors. He stated that failure to meet those requirements is not a stand-alone basis to find a selection patent invalid [FC 104], and he rejected anticipation [FC 83] and obviousness [FC 88] attacks without reference to the factors, though he did go on to hold that if compliance with the IG Farbenindustrie factors were required, the 202 Patent meets that test [FC 106–08].

So, the continued vitality of the IG Farbenindustrie factors and their relationship to the standard grounds of invalidity remains unclear. The FCA will no doubt clarify that relationship in due course, but chose not to do so in this decision. On appeal, Pharmascience argued that Zinn J erred because he never made a clear finding that the 202 patent is a selection patent. Locke JA noted that Zinn J had nonetheless clearly held that the 202 patent satisfied the IG Farbenindustrie criteria and in particular that it disclosed the special advantages of apixaban (the first factor, and typically the most important) [12]. The FCA then went on to separately affirm Zinn J on anticipation and obviousness, without reference to the IG Farbenindustrie factors as such [16]–[21]. Thus, it is not clear whether Locke JA considered it necessary for Zinn J to address the IG Farbenindustrie factors.

Requirement to disclose the special advantage

The most commonly applied IG Farbenindustrie factor is the first, requiring that “There must be a substantial advantage to be secured or disadvantage to be avoided by the use of the selected member” Sanofi [10.1]. This is readily seen as a reflection of the non-obviousness requirement in the context of selection patents. If the prior art discloses a large genus of compounds and discloses that all members of the genus possess a certain property, eg all the compounds treat cancer, then it is not inventive to select one species from that genus and show that it treats cancer, since we already knew that all members of the genus treat cancer. To select one species from a genus is an “arbitrary selection” discussed here and here. A selection must therefore have some special advantage—it cures cancer with fewer side effects, or with higher efficacy—compared with what was known about the genus as a whole.

In this case, Pharmascience argued that Zinn J “erred in failing to recognize (i) that the 202 Patent did not indicate a special advantage, and (ii) the requirement that a selection patent disclose the special advantage of the selection (because the special advantage is the invention, and a patent must disclose its invention” [11]. That is, the argument is not just that apixaban must have a special advantage over the compounds of the 330 patent, but that the special advantage must be disclosed in the 202 patent. This argument seems to be ultimately derived from Sanofi-Aventis v Apotex 2013 FCA 186 [51] (though that case was not cited), where the FCA said “In the case of selection patents, as we have seen, the novelty of the selection and its advantages (including disadvantages to be avoided) are the invention and must be described in the patent,” relying at [45] on Sanofi 2008 SCC 61 [114] (and also Olanzapine 2010 FCA 197 [78], which cited the same paragraph of Sanofi.) Sanofi in turn stated

[114] While double patenting requires a comparison of the claims of a genus and selection patent, it is necessary that the specification of the selection patent define in clear terms the nature of the characteristic which the patentee alleges to be possessed by the selection for which he claims a monopoly. See I. G. Farbenindustrie, at p. 323.

The SCC was evidently referring to the following passage from IG Farbenindustrie:

It should be obvious, after what I have said as to the essence of the inventive step, that it is necessary for the patentee to define in clear terms the nature of the characteristic which he alleges to be possessed by the selection for which he claims a monopoly. He has in truth disclosed no invention whatever if he merely says that the selected group possesses advantages. Apart altogether from the question of what is called sufficiency, he must disclose an invention; he fails to do this in the ease of a selection for special characteristics, if he does not adequately define them. The cautions repeatedly expressed in the House of Lords as regards ambiguity have, I think, special weight in relation to selection patents.

This all looks like good authority for the proposition that a valid selection patent must disclose the special advantages. (Though the reference to ambiguity is a bit mystifying.)

The difficulty with this proposition is that it is well-established that the inventive concept that renders the invention non-obvious need not be disclosed: see Raleigh v Miller (1948) 65 RPC 141 (HL) 161 (Lord MacDermott) stating “a patentee is not bound to include in his specification a statement of the inventive step”; Consolboard [1981] 1 SCR 504, 532-33; BUSM v Fussell (1908) 25 RPC 631 (CA) 649-653. The specification must disclose an invention—which is to say, subject-matter that is in fact new, useful, and non-obvious—but it is not necessary for the specification to disclose what makes it an invention. There has been some confusion on this point because it was at one time necessary in English law that the patent should distinguish what is new from what is old, on the view that the specification ought to inform the public of the bounds of the monopoly. But that function is now served by the claims, which serve that purpose by defining the scope of the monopoly directly, rather than by distinguishing old from new: see BUSM v Fussell (1908) 25 RPC 631 (CA) 650-51, explaining that the rule became outdated with the advent of claims. So, it is now well-established that it is not necessary to describe in what respect the invention is new. So long as the claimed invention is in fact novel and sufficiently disclosed, “There is no obligation to go further, and to state why it is novel, or what in it is novel”: Consolboard [1981] 1 SCR 504, 531-32, quoting with approval BUSM v Fussell (1908) 25 RPC 631 (CA) 651. The same principle applies to obviousness.

Given that there is no general requirement to disclose the inventive concept, either there is no requirement to disclose the special advantage of a selection, or there is some special rule that applies only to selection patents, and the latter is contrary to the Olanzapine principle that “A selection patent is the same as any other patent. Its validity is vulnerable to attack on any of the grounds set out in the Act.”

As the SCC pointed out in Consolboard at 532, a contrary rule would “impose[] an impossible burden on the patentee. Suppose he was not aware of another invention that was very similar to his own. If he failed to specify the differences between the two inventions, the patent would be invalid notwithstanding that his invention was new and different.” It would be “grossly unjust” to require the inventor to keep abreast of every development in her field, nor would such a requirement benefit the public: BUSM at 652, quoted in Consolboard at 532. So, suppose that the inventor in this case was not aware of the 330 patent, notwithstanding that it was prior art; it would then be impossible for the patent to specify the special advantages of apixaban over the compounds disclosed in the 330 patent.

In any event, Locke JA did not have to address these issues because he held that the patent did in fact disclose special advantages of apixaban [12], though he did state that “There was no need for the 202 Patent to provide an explicit comparison of apixaban to any other particular compound falling within the scope of the 330 Patent” [14]. He also stated that “There is no requirement for a selection patent to discuss the special advantages of the selection over the genus in any particular way” [38]. This is ambiguous, as it is consistent with the view that it is necessary to disclose the special advantages, just not in a particular way, such as explicit comparison with the genus compounds.

Usefulness as the special advantage

The decision also raises a different issue. Locke JA noted that the special advantage of apixaban is that “it was useful” [12, quoting FC 107, original emphasis]. The fact that apixaban is useful is a special advantage over the compounds of the 330 patent because “the skilled person reading the 330 Patent would understand that not all of the claimed compounds would be useful in treating and preventing thromboembolic disorders” [12, quoting FC 107]. This is consistent with the view that the first IG Farbenindustrie factor is a reflection of the non-obviousness requirement, as Locke JA made the same point in the context of the obviousness discussion. He noted that Zinn J identified the inventive concept as the selection of apixaban from the other compounds of the 330 patent, and that the difference between the inventive concept and the state of the art, reflected in the 330 patent, was that apixaban was “effective” in treating thromboembolic disorders, as opposed to the compounds of the 330 patent, which merely had the “potential” to be useful [20].

This is a bit odd on its face. If the 330 patent were valid, then we would know that the compounds encompassed by it, including apixaban, are sufficiently useful to satisfy the utility requirement. If the genus is useful and we pick a species out and say it’s useful too, isn’t that just arbitrary selection? As the defendants argued “It is obvious that apixaban can be used to treat thromboembolic disorders as the 330 Patent states that the bicyclic compounds claimed therein (which include apixaban) are effective FXa inhibitors and are useful for the treatment of a thromboembolic disorder” [FC 85]. This may be a reference to the statement in the 330 disclosure that “These and other objects, which will become apparent during the following detailed description, have been achieved by the inventors' discovery that the presently claimed bicyclic compounds, or pharmaceutically acceptable salt or prodrug forms thereof, are effective factor Xa inhibitors.”

There are a couple of answers. First, assuming the 330 patent is valid, the bar for patentable utility is low, requiring merely a sound prediction of utility for the claimed compounds. Selecting a compound that is actually useful from among many that are merely predicted to be useful is arguably inventive, assuming, as Zinn J found at [FC 87], that the search is difficult enough. This is not very different from the advantages of the selected compound in Sanofi, which had “greater therapeutic effect and less toxicity” [78] than the other compounds of the genus. (It seems clear that there is nothing special about lower toxicity; no doubt greater therapeutic effect alone would suffice.) While the 330 compounds and apixaban both satisfy the utility requirement, maybe the 330 compounds barely clear the hurdle and apixaban cleared it easily. That is the thrust of both Zinn J and Locke JA’s reasoning on this point, though the point might perhaps have been made more clearly. Zinn J did not draw a direct comparison between the utility of the genus and apixaban, and while he did find that apixaban was useful, he did not state explicitly that it surpassed the standard easily. With that said, the evidence he accepted that the studies “really leaves no doubt” that it would be therapeutically useful in humans certainly indicates that it substantially surpassed the relatively low bar for patentable utility.

In any event, even if we don’t know whether the 330 patent is valid. We know that many granted patents are invalid, and it is possible that most of the compounds are actually not useful at all, even on the basis of sound prediction. In that case, selecting a truly useful compound could well be a special advantage. One way or the other, the bottom line is that just because the 330 patent says the disclosed compounds are effective, there is no particular reason to believe that statement.

The apparent puzzle largely disappears if we simply ignore the fact that the patent is a selection and treat the genus patent as prior art with no special status. If the genus patent in fact establishes that all compounds withing its scope will actually be effective, then selecting one from the group will be obvious. But if it simply indicates a direction to be explored, and actually finding a useful compound is arduous, then there should be no objection to granting a patent to the successful explorer. On that view, the key aspect of the decision is Zinn J’s statement that the invention was “the result of hard work, innovative thinking and a bit of good luck” [87], though that is somewhat conclusory; see also the evidence, accepted by Zinn J in the context of anticipation, to the effect that it would be only a small percentage of the genus compounds that would be safe and effective in treating thromboembolic disorders [FC 81]. I wonder if the question of whether apixaban had unexpected utility over the genus patent might have been addressed more explicitly if the genus patent had simply been treated as part of the prior art, rather than framing the issue in terms of a selection patent.

Skinny Label and Swiss Claims

Janssen Inc v Apotex Inc 2022 FC 996 (reasons) 2022 FC 995 (judgment) Pallotta J

            2,659,770 / macitentan / OPSUMIT / NOC

There are three known biological pathways affecting pulmonary blood pressure, namely the prostacyclin, nitric oxide, and endothelin pathways. PDE5 inhibitors, such as tadalafil, work through the nitric oxide pathway. Macitentan is an endothelin receptor antagonist (ERA), which, as the name suggests, works through the endothelin pathway. The 770 patent relates to the use of combination therapy consisting of macitentan and a PDE5 inhibitor (PDE5-I) to treat diseases involving vasoconstriction, particularly pulmonary arterial hypertension (PAH). Most PAH patients are treated with combination therapy, but a non-trivial number of patients — around 20% — are treated with macitentan monotherapy [162]. Janssen markets OPSUMIT, a 10 mg tablet, for use alone or in combination therapy. Apotex sought to market a 10mg tablet of macitentan, which is not itself patented, and in this NOC action, Pallotta J held that Apotex’s macitentan product would infringe Janssen’s 770 patent. Validity was not at issue [9]. The 770 patent was also at issue in Janssen v Sandoz 2022 FC 715, in which infringement was conceded and validity was at issue: see here.

This is in many ways a typical ‘skinny label’ case, in which a generic seeks to sell a drug that is itself unpatented, but which may be used in a manner that is patented, eg as part of a patented combination, or for a patented indication. The generic in such cases is not normally a direct infringer, so infringement by inducement must be established under the three-part Corlac test, 2011 FCA 228 [162]. This typically reduces to the question of whether the generic’s product monograph (PM) will induce infringement by prescribing physicians, who will read the monograph and thereby be induced to prescribe the generic product for use in an infringing manner. A central question is therefore whether the generic’s skinny label has been sufficiently scrubbed clean of any reference to the infringing use. This inquiry turns on the details of the PM. Sometimes the generic wins, sometimes it loses—as in this case. The generic will also sometimes argue that even if its PM does instruct an infringing use, that doesn’t constitute infringement because the prescribers don’t pay any attention to the generic PM in any event. Whether prescribers heed the generic PM is a fact-specific inquiry, but so far as I know, no generic has ever prevailed on this argument. (Please leave a comment with a case cite if I am wrong about that.) Apotex made that argument in this case, and, unsurprisingly, lost. The result was that Apotex was enjoined from marketing Apo-macitentan until after the expiry of the 770 patent. While the case was typical in broad outlines, there are a few issues of interest in this decision, particularly on the construction of Swiss-type claims.

Three types of claims were at issue in this case [86]:

Product for use

Claims 1–5 eg “A product containing [macitentan] . . . in combination with [a PDE5-I] . . . for therapeutic use. . . in the treatment of [PAH].”

Use for treatment — sometimes referred to as German-style claims

Claims 21–31 eg “A use of [macitentan] in combination with [a PDE5-I] for treating [PAH].”

Use in manufacture of a medicament for — commonly called Swiss-form claims

Claims 10–20 eg “A use of [macitentan] in combination with [a PDE5-I] . . . for the manufacture of a medicament intended to treat [PAH].

A variety of claim types are employed because many jurisdictions have some kind of prohibition on patenting of methods of medical treatment, and consequently a variety of claim forms are used in claiming the use of a compound to treat a disease. A fourth type of claim that is often used in the US is straightforward: “A method of treating disease Y, comprising administering compound X.” This type of claim is not allowed in Canada as it is considered to fall afoul of the prohibition on patenting methods of medical treatment.

A preliminary issue was as to the construction of “combination,” which Pallotta J construed as including any scenario in which macitentan and the PDE5-I work in concert to treat the disease in question. In particular, it does not matter whether the macitentan and PDE5-I are combined in the same dosage form [120]; and it includes a scenario in which the patient is started on macitentan monotherapy and then moved to a combination therapy of macitentan and PDE5-I [116].

The most interesting claim construction issue concerned the interpretation of the Swiss-type claims. Swiss claims were originally developed to avoid the European prohibition on patenting of methods of medical treatment. Since a Swiss claim is, on its face, a claim to the product, not its use, and the physician who prescribes a drug does not manufacture it, physicians are excluded from the scope of infringement. However, in Hoffmann-La Roche v Sandoz 2021 FC 384, [95]–[109], Manson J held that the Swiss claims should be construed as use claims on the basis of a purposive interpretation; in effect, the idea is that what was really discovered was a new use, not a new method of manufacture, and the claim should be construed in light of what was actually discovered [97]. The result was that the generic, Sandoz, could not be liable as a direct infringer. As discussed here, this is a bit of a strange result, because it means that prescribers are direct infringers and the manufacturer is not, even though the original purpose of Swiss claims was to ensure that the manufacturer a direct infringer and the prescriber is not an infringer at all.

In this case, Apotex, relying on Hoffmann-La Roche, argued that the Swiss claims should be construed as use claims, so that Apotex could only be liable, if at all, on the basis of inducement. Pallotta J did not accept this argument. While a purposive construction may consider the nature of the inventive concept, “a purposive construction focuses on the language of the claims,” and “[t]he words chosen by the patentee necessarily play a key role” [128]. The importance of the text is consistent with the general law of statutory interpretation: Canada Trustco 2005 SCC 54 [10]; Canada v Utah 2020 FCA 224 [9]; Biolyse v Bristol-Myers Squibb 2003 FCA 180 [13]. It is also well-established as a principle of claim construction: Free World 2000 SCC 66 [39]–[40]; ABB Technology 2015 FCA 181 [42]–[43] (cited by Pallotta J at [128]. The words of the Swiss claims clearly claim the use “for manufacture of a medicament” [128].

While I’ve waffled a bit on this (see my comments on Warner-Lambert) I think Pallotta J is right on this. The key doctrinal point is that the words play a “dominant role” in the interpretive process, as the SCC put it in Canada Trustco. This is important in the context of statutory interpretation because the legislature must be able to rely on the courts to carry out the legislature’s intent, and the words, when clear, are the best reflection of that intent. The parallel point in the context of claim construction is that the patentee should be able to decide what it wants to claim—taking the risk that the claim may be invalid—and again, the words it uses are the best guide to that intent. If there is some public policy reason that Swiss form claims should not be permitted at all, then this should be implemented through a substantive legal rule, which can then be debated and subject to appeal.

Even though Pallotta J came to a different conclusion than Manson J, she did not have to expressly disagree with his analysis, as Manson J held that the meaning was context specific [103] and his holding of law was only that Swiss claims do not “automatically benefit[] from a literal construction” [102]. I must say I am not very enthused about that approach. Patent agents take great pains with the words used in a claim. While some terms used will be specific to the invention, and so may require considerable context, there are some terms, such as “comprising,” which are effectively terms of art with a specific meaning, and which should accordingly be given a consistent meaning. To my mind, Swiss claims are sufficiently common and established as a claim form, that they should be given a standard construction, so that patent agents will be able to predict the consequences of using Swiss claims.

Even though Palotta J construed the Swiss claims as product claims, she nonetheless held that neither the Swiss claims, nor the product-for-use claims, were directly infringed by Apotex. She noted that Apotex only intended to sell macitentan itself, not a product that contains macitentan in combination with a PDE5-I. Consequently, she held that Apotex did not infringe the product-for-use claims, which claim ‘A product containing [macitentan] in combination with [PDE5-I]’ because the product sold by Apotex would not contain the drugs in combination [144]. This reasoning seems right to me. She held that the Swiss claims were not infringed for the same reason [144]. This also seems right, given the structure of the Swiss claims at issue: “A use of [macitentan] in combination with [a PDE5-I] . . . for the manufacture of a medicament intended to treat [PAH].” This indicates that macitentan and the PDE5-I are used in combination for manufacture of the medicament.

As an aside, it occurs to me that a more difficult question would arise if the Swiss claims were of the form “A use of [macitentan] for the manufacture of a medicament intended to treat [PAH] in combination with [a PDE5-I].” In that claim, the question is whether the macitentan is intended for combination use, which, given Pallotta J’s holding that “in combination” encompasses any scenario in which the drugs work in concert, would include administration of separate pills in combination therapy. In that hypothetical, the question would be whether the generic product was intended for use in combination therapy. As discussed here, in Warner-Lambert v Generics (UK) [2018] UKSC 56 the UKSC split three ways in trying to decide what “for” means, with two variations on an objective intent test, plus a subjective intent test, not to mention the modified objective foreseeability test endorsed by the EWCA. Using the hypothetical claim, the generic might be a direct infringer on either the objective or subjective intent approach, depending on whether, on the facts, it subjectively or objectively intended macitentan to be administered in combination with a PDE5-I. I would stress that I am not endorsing either of these approaches, but simply pointing out that a more difficult issue would have arisen had the Swiss claims been framed differently.

With construction settled, Apotex argued that its PM did not instruct the use of macitentan in combination therapy. Pallotta J rejected this argument on the facts. It’s a bit hard to follow because of redactions, which, though brief, obscure the precise nature of the references. If I understand correctly, the main trial which established the safety and efficacy of macitentan as a monotherapy – “SERAPHIN” — also established its efficacy as a combination therapy [153]. The Apotex PM contained clinical trial data from SERAPHIN [192], [193], and SERAPHIN was so well known [187] that the references to it in the Apotex PM would be enough to alert physicians to the fact that macitentan is effective in combination therapy, and so would induce infringement [192], [199]. This is even though the APO-MACITENTAN PM “removed all mentions to the use of macitentan as a combination therapy that are present in the OPSUMIT PM, and only mentions SERAPHIN results that reported macitentan was useful as a monotherapy” [164]. It is true that the courts have been stringent about ensuring that the generic PM is scrubbed clean of references to the infringing use, but this seems pretty harsh on Apotex, given that it had to include the clinical trial data to establish efficacy as a monotherapy. I must say that I suspect that one factor in Pallotta J’s analysis is the fact that combination therapy is the primary use for macitentan, with only 10–30% of patients getting monotherapy [162]. If the opposite were true, so that eg only 10% of the use was in the patented combination, then I wonder if it would have gone the other way. Of course, in that scenario, it is perhaps unlikely that the main clinical trial data would be for the combination therapy.

Apotex also argued that even if the PM did instruct infringing combination therapy, this did not matter because prescribers don’t pay attention to the PM anyway: “In the field of PAH, the physicians know SERAPHIN very well and it does not matter what is contained in APO-MACITENTAN PM” [166]. This argument failed on the facts [197], as it always does. (If anyone knows a case where this argument has succeeded, please let me know in the comments.) The argument makes sense in theory, given the requirement that the influence be the “but for” cause of direct infringement, but if successful, it would mean that generic would in theory be able to sell a drug with the infringing use plastered all over the PM, on the basis that the PM is irrelevant anyway. I suspect that a desire to avoid this strongly counter-intuitive result might help explain why the courts invariably come to the conclusion that at least some prescribers are influenced by the PM. (Of course, it’s also possible that it’s simply true that at least some prescribers are influenced by the PM.)

Finally, Pallotta J emphasized that in light of this influence, Apotex would induce infringement “even if a physician applies their own skill and judgment to the decision to prescribe combination therapy” [156]: see similarly [181]. Pallotta J remarked that “[i]f it were otherwise, inducing infringement could never be found in the context of pharmaceutical patents” [156]. In any event, I don’t really see any difficulty with this position. As Pallotta J also noted, “a ‘but for’ test does not mean that Apotex’s activities must be the sole cause of the infringement” [156]. A physician who learns from the PM that macitentan is useful in combination therapy to treat PAH must still use their skill and judgment to determine that their patient is suffering from PAH. Conversely, a physician who has determined that their patient is suffering from PAH will not prescribe macitentan combination therapy unless they have learned somewhere that it is effective in treating PAH; and if they learn that from the PM, the information in the PM is the ‘but for’ cause of the infringement, even if it is not the sole cause of the infringement.

Divided Infringement and Problems of Multiple Parties

Rovi Guides, Inc v Videotron Ltd 2022 FC 981 Brown J

            2967187 / 2635571 / 2775674 / 2553922

Rovi Guides, Inc v BCE Inc 2022 FC 979 Brown J

2753243 / 2631957 / 2952467 / 2691719

These companion decisions raise the difficult issue of divided infringement, which arises when a patented invention is jointly put into effect by two different entities, so it is difficult to identify a single infringer. The problem is particularly important in method claims, including personalized medicine and internet-related inventions, where one party practises some element of the method and a different party practises the remaining elements. An example is the invention at issue in the leading US decision, Akamai v Limelight 797 F3d 1020 (Fed Cir 2015) (en banc)*. Akamai involved a method claim relating to methods for delivering content over the internet. The defendant, Limelight, operated a content delivery network. Limelight carried out several steps of the claimed method, but Limelight’s customers, not Limelight itself, performed the remaining steps of the claimed method, namely ‘tagging’ and ‘serving’ (1024). Between them, Limelight and its customers put the claimed invention into practice, but neither individually practised all the steps. The question was whether Limelight is liable for infringement.

These companion decisions appear to raise similar issues. The patented inventions relate to “interactive television program guides” [IPG]—the familiar interactive menus used to select current and upcoming programs. The nature of the technology is not discussed in detail, since the motion to strike turned on the law, but it is clear enough that it raised problems of infringement involving multiple parties. Brown J, affirming the decision of Aalto CMJ, refused to strike allegations of infringement by common design and infringement by attribution, This does not, of course, mean that these are necessarily good causes of action, but the decision does confirm that the law of infringement involving multiple parties requires further development. Because the facts of this case are not clear, for the purposes of the following discussion I’ll treat Akamai as a paradigmatic example. The reasons are somewhat better developed in the Videotron decision and in this post paragraph numbers will refer to that decision.

In the simplest type of infringement, a single natural person practices all elements of the invention. But practising the invention may, and commonly does, involve multiple parties. This does not necessarily raise doctrinal difficulties. For example, if the alleged infringer subcontracts with another party to make a part for a patented invention, and then takes delivery of the part and incorporates it into the completed invention, the alleged infringer will be directly liable by virtue of having itself made the invention, without any need to attribute the acts of the subcontractor to the primary party. But other contexts involving multiple parties may raise more difficult problems; for example, where one party encourages another to infringe (inducement), or in the context of method or process patents, where one party performs some of the steps of the claimed method or process and another performs the remaining steps (divided infringement).

These scenarios create a tension between two principles. On the purposive definition of infringement, the patent is infringed when the patentee is deprived of the benefit of the invention: Monsanto v Schmeiser 2004 SCC 34 [44]. If the invention is in fact put into effect by someone else, the patentee is deprived of that benefit whether it was put into effect by one person or two people acting together. On the other hand, patent infringement is a strict liability tort—a party will be liable if it performs the acts constituting infringement, whether or not it intended to infringe. Since the patent is a public document, a potential infringer can in principle determine whether it is infringing by comparing its acts to the claimed invention to determine if it is practising the invention. We shouldn’t exaggerate the efficacy of a freedom to operate search; even in simple cases of direct infringement by a single party, the practical difficulty of identifying relevant patents can create uncertainty. But the problem is evidently substantially worse if a party can be made liable even though it is not putting all the elements of the invention into effect. Consequently, the main objection to imposing liability for divided infringement is that making a party liable for performing only one element of an invention introduces uncertainty and a consequent chilling effect: see Limelight v Akamai 572 US 915 (2014) 922; Akamai v Limelight 786 F.3d 899 (Fed Cir 2015) 905. Dealing with the chilling effect is a key issue in infringement involving multiple parties. I’ll suggest that a common thread in the doctrines that extend liability beyond the case in which a single entity which itself directly practices the invention is that the defendant who is made liable for infringement has the same opportunity for knowledge, or at least control, as a natural party who practices all elements of the invention itself.