When can a range anticipate a point?

AbbVie Corporation v JAMP Pharma Corporation 2023 FC 1520 McVeigh J

2,504,868 / 2,801,917 / 2,904,458 / adalimumab / HUMIRA / SIMLANDI

The most important aspect of this case was McVeigh J’s refusal to grant a permanent injunction to the successful patentee. I will discuss that in a separate post. McVeigh J also had a brief discussion of double patenting, which I discussed in a previous post that focused on NCS v Kobold 2023 FC 1486. This post provides an overview and addresses some miscellaneous issues, including McVeigh J’s brief but helpful discussion of as to when prior art that discloses a range can anticipate a point within a range.

This case involved three patents related to adalimumab, which is well known under the brand name HUMIRA for treatment of rheumatoid arthritis, inflammatory bowel disease (IBD) and psoriasis. The 868 patent relates to a dosing regimen for a known use (the treatment of IBD). McVeigh held the 868 patent to be invalid as being obvious to try [303], though an attack based on patentable subject matter failed [339]. The 917 patent relates to a second medical use — the treatment of hidradenitis suppurativa (HS) — and a dosing regimen. It seems that the use of adalimumab to treat HS was known [400], so the key issue, as with the 868 patent, was whether the dosing regimen was obvious. McVeigh J held on the facts that it was [402]. An attack based on patentable subject matter failed [413]–[415]. There was also an unusual attack based on “Claim term not described” which I will come back to. The 458 patent related to an adalimumab formulation, which McVeigh J found on the facts to be not anticipated [559] and not obvious [591]. Attacks based on overbreadth [592]–[603] and double patenting [604]–[620], also failed.

Identical Witness Statements

As discussed here, in dTechs 2023 FCA 115 [32], [34], the FCA addressed the role of counsel in the preparation of expert reports. Gauthier JA noted that while it is not unusual for expert reports to be prepared “in close collaboration with counsel,” this is not normally a significant problem, so long as the Court is ultimately “presented with the substantive and objective opinion of the expert.” Gauther JA also noted that “While counsel may make mistakes and overstep the bounds of what is permissible involvement, this will normally be revealed on cross-examination at trial, and will be considered by trial courts in assessing the evidence” [34]. Something along those lines happened here, albeit with a fact witness:

[210] Dr. Noertersheuser suffered significant credibility issues. It became apparent during his cross-examination that much of his statement was nearly identical, or word-for-word the same, as a witness statement made by Dr. George Richard Granneman on December 18, 2017 in US litigation. While this is not, in and of itself, hugely problematic, his responses on cross-examination reduced his credibility. He attempted to explain that perhaps he and Dr. Granneman had written identical statements because of how closely they had worked together in the past. He said they worked side by side and discussed things back then, and that must have been the reason they wrote identical statements. He was asked several times and confirmed that he independently came up with the exact same words but that he never copied. This is clearly inaccurate, and he would have better served the Court by admitting the statements were copied, instead of trying to claim that it was sheer coincidence.

[212] Unlike in Rovi, Dr. Noertersheuser was not an expert witness. Nonetheless, the word-for-word copying of Dr. Granneman’s report raised significant concerns about Dr. Noertersheuser’s impartiality. His inability to accept or acknowledge the paragraphs were word-for-word the same greatly impugned his credibility and reliability.

[215] The similarity between Dr. Noertersheuser (fact witness) and Dr. Granneman’s expert report went well beyond the appropriate limits. I will assess Dr. Noertersheuser’s evidence with some caution when it is in disagreement with other witnesses.

Treating his evidence with “some caution” is a very measured response.

Blinding the Witness

Over the past decade there have been various attempts to enhance the credibility of an expert on issues such as claim construction or obviousness by not informing the expert of the party’s position when they write their report. While some earlier decisions supported this practice, the trend more recently has been to be skeptical, generally on the view that the substance of the report is more important than whether the witness was blinded. Another concern is that it may impossible to truly blind a person who is an expert keeping abreast of developments in a particular field: see eg Hospira 2018 FC 259 [203]. That problem arose in a particularly acute form in this case, when one of the experts who had been ‘blinded’, forgot that she had previously provided expert evidence in another matter involving the 868 patent [247]–[249], [252]. McVeigh J expressed skepticism of the worth of the blinding process, saying “I rely on Dr. Baughman’s evidence, not for the fact that it was blinded but for the reasoning it provides” [250]. McVeigh J did not fault Dr. Baughman, whom McVeigh J found to have sincerely failed to recall her prior involvement”; nonetheless, while she did accept the evidence as credible and reliable, she only assigned a moderate weight to it [252].

When can a range anticipate a point?

The parties disagreed “as to whether prior art that discloses a range can anticipate a point within a range or embodiment. For example, has disclosure occurred if the range is 0.2-400 mg in the prior art, and the subsequent patent claims about 10 mg or a narrower range such as 0.10-100 mg” [157]. JAMP relied on several recent cases in which “the Federal Court held a range or a broad disclosure can anticipate a point within a range or an embodiment” [158]. After reviewing those cases, and discussing several blog posts in which I have argued that these decisions were clearly wrong, McVeigh J concluded as follows:

[173] I find that the law has developed that, where the evidence presented at trial shows that the range is narrow enough, such that a flag can be planted based on the context and examples given, then it is anticipated. If the evidence shows a very broad range that the Judge, with the experts’ assistance (if needed), does not see it as a precise enough to plant the flag before proceeding to the enablement stage, then it fails at the disclosure stage.

This statement of the law strikes me as sound and helpful (though I’m not sure it actually explains the prior cases or whether McVeigh J intended it as doing so). It is consistent with the EPC Examination Guidelines G.VI.8, which also strike me as sound:

A sub-range selected from a broader numerical range of the prior art is considered novel if both of the following two criteria are satisfied (see T 261/15):

(a) the selected sub-range is narrow compared to the known range;

(b) the selected sub-range is sufficiently far removed from any specific examples disclosed in the prior art.

The meaning of "narrow" and "sufficiently far removed" has to be decided on a case by case basis.

McVeigh J also applied her analysis to the facts in two instances, both holding that there was no anticipation.

JAMP argued that the asserted claims of the 917 Patent were anticipated by the 868 application [383]. Recall that the 917 patent relates to the use of adalimumab, a TNFα inhibitor, to treat HS according to a specified dosing regimen. The 868 application disclosed the use of TNFα inhibitors as a means of treating 16 broad categories of disorders, including HS, and presenting a large class of dosing elements with numerous choices for the specific TNFα inhibitor, the number of loading doses, the amount for each loading dose, the interval between loading doses, the interval between loading and maintenance dose (one hour, one day, one week, two weeks) and the amount of maintenance dose [387]. So, “a skilled person reading the 868 Application would have a range of dose amounts, dosing intervals, and durations of treatment to choose from when creating a multiple variable dosing regimen to treat an inflammatory-related disorder” [388]. In contrast, the 917 Patent claimed a much more specific dosing regime [389]. McVeigh J invoked her para 173 analysis [385] and concluded:

[390] Given the number of dosing elements disclosed in the 868 Application, it is not clear that a POSITA would know to select adalimumab and to administer it using the specific dosing regimen claimed in the 917 Patent. If the POSITA reading the prior art reference must adopt a specific way forward in order to infringe, yet there are numerous other ways to perform the prior art without necessarily infringing, then there is no disclosure: Shire [2021 FCA 52] at para 50.

This strikes me as straightforwardly correct, and consistent both binding jurisprudence, such as Shire and with McVeigh J’s summary statement at [173].

JAMP also argued that the asserted claims of the 458 Patent, claiming a formulation of adalimumab, were anticipated by the 181 Application, titled “Self-Buffering Protein Formulations” [539]. The 181 Application listed adalimumab among the proteins:

[545] The most preferred protein concentration range in the 181 Application is 20-150 mg/mL. This is a very large range. For the four proteins tested whose test results appeared in the 181 Application, there were concentrations of 90 mg/mL and 110 mg/mL which proved to be self-buffering within pH ranges which included 5.2. But there were other ranges tested too, and none of these proteins were adalimumab. Moreover, in the claims section of the 181 Application, these proteins are not introduced in the same claim as adalimumab and there is no indication of dependency between the claims that introduce these proteins and the claim which refers to adalimumab.

[546] As mentioned above, a range does not always anticipate a point, but it could if dependant on the facts of the particular patent. This is even truer where the range is very large or broad. Accordingly, I do not see how a range of protein concentration from 20-150 mg/mL can plant a flag at the specific concentration of 100 mg/mL, especially where specific examples of formulations given do not include the relevant protein.

Accordingly, she held the 181 application did not anticipate. Again, this strikes me as straightforwardly correct, and consistent both the binding jurisprudence and with McViegh J’s summary statement at [173].

Methods of medical treatment

It is still black letter law that methods of medical treatment are not patentable subject matter, though the jurisprudential basis for that proposition is shaky: see Hospira 2020 FCA 30 [48]–[49] (discussed here). However, no one really knows what a “method of medical treatment” is. That’s because there is no clear principle underpinning the rule. The rule was originally set out by the SCC in Tennessee Eastman [1974] SCR 111, primarily on the very logical basis that allowing patentability of methods of medical treatment would allow an end-run around what was then s 41, which restricted patents for medicine to product-by-process claims. Section 41 has since been repealed, but Tennessee Eastman had a tantalizing dictum — “I do not think so” — suggesting there might be more to it than that. Subsequent decisions of the SCC suggested that the bar might turn on the “essentially non-economic” nature of the methods of medical treatment: see Hospira 2020 FCA 30 [49], discussing Shell Oil [1982] 2 SCR 536, 554 and Wellcome / AZT 2002 SCC 77 [49]. But no one really knows what it means to say that professional skills are essentially non-economic. (Try telling that to a lawyer.)

In any event, the best current theory is that a claim that encompasses the skill of a medical professional is unpatentable. To say it’s the best theory is not to say it’s a correct theory, or even a good theory — see Hospira [51]–[52] — but that’s more or less where we are now. The problem is that no one really knows what it means for a claim to encompass the skill of a medical professional. As a result, we are all flailing in trying to give some kind of content to the putative rule that methods of medical treatment are unpatentable.

In this case, JAMP argued that the claims of the 868 and 917 patents, both directed to dosage regimens, were invalid as being directed to a method of medical treatment that requires the exercise of professional skill or judgment [332] saying that:

[333] where there is evidence that the dose would be changed over time in response to a patient’s needs, then that regimen is vulnerable to an attack on the basis that is an unpatentable method of medical treatment. In JAMP’s view, the dosing regimen must be appropriate for all.

McVeigh J rejected this argument, quoting the decision of Manson J in Janssen 2022 FC 1218 [171] (discussed here) to the effect that if a physician departs from the claimed dosage regimen “they would no longer be practicing the claimed invention” [338]. She followed this reasoning, concluding that “to the extent a minority of physicians wish to deviate from the claimed regimens at some point, this does not render the claims unpatentable; rather, it takes their conduct outside the scope of the patents like in Janssen” [339]. See similarly [413]–[415] respecting the 917 patent.

More broadly, this suggests that the incoherent state of the law has made the Federal Court wary of striking down patents on the basis that they claim unpatentable methods of medical treatment. This wariness strikes me as being entirely appropriate. This bar on patentability has no basis in the Act. While the courts can and do read text into a statute, this is normally done only after a careful purposive interpretation shows that adhering to the text would lead to an absurd or otherwise unacceptable result. The courts are right to be reluctant to use a judge-made doctrine to strike down a patent for an invention which is otherwise new, useful and non-obvious, without some clear principled basis for doing so.

Doses not subject to discretionary adjustment

The 917 patent claimed a dosage regimen “wherein said multiple doses are not subject to any discretionary adjustment by a physician or medical practitioner” [380]. This phrase was added by AbbVie during prosecution to overcome an examiner objection that the claim was to a method of medical treatment because it limits the professional skill or judgment of a physician [441]. The issue came up as part of an added matter attack, which I will return to below. For now, I’ll just point out McVeigh J’s remark that “AbbVie’s addition did not change claim 1, nor does it broaden the claim. Claim 1 would have had the same effect, with or without the additional statement” [443]. This is a relief. I don’t want to get too far into the weeds of how this phrase might be construed. (Surely any dosage regimen is subject to discretionary adjustment in some cases, eg if the patient has an unexpected life-threatening reaction to the first dose—would that mean all claims with that phrase would be invalid?) The larger point is that McVeigh J’s statement suggests that the issue of patentability of methods of medical treatment will be decided on substantive grounds, not by trying to make the issue disappear with drafting slight of hand. When the law is settled, but unworkably, it may be necessary to allow the use of drafting methods to get around the black letter law, as was done with Swiss form claims. But that is a second best solution. It is better to get the substantive law right in the first place, and the law on patentability of methods of medical treatment is currently sufficiently unsettled to allow us to try to do that.

Added matter

JAMP attacked the 917 patent for failure to comply with s 38.2(2): see [192]–[197], reviewing the law, and [416]–[444], further reviewing the law and applying it to the facts. This attack was referred to as a “Claim Term Not Described,” but I’ll call it an “added matter” attack, as is this the conventional term for the parallel issue in UK law. The issue arises regularly in UK law, because claim amendments are permitted in litigation, and the question is whether the amended claim impermissibly adds new matter. There is limited Canadian caselaw on this provision, with the main authority being Western Oilfield 2021 FCA 24 (discussed here).

38.2(2) provides as follows:

The specification and drawings contained in an application, other than a divisional application, may not be amended to add matter that cannot reasonably be inferred from the specification or drawings contained in the application on its filing date.

One issue that was raised was whether this provision can be the basis for an invalidity attack, or whether it is purely procedural.

After reviewing the authorities, including Western Oilfield, McVeigh J concluded that “the law currently stands, it is unclear whether a patent is invalid when a party adds a claim term that cannot be reasonably inferred from the specification or drawings” [197]. Western Oilfield is perhaps a bit ambiguous. The main issue was the nature of the test for whether the new matter could be inferred, and specifically whether the Canadian courts should follow the “strict” UK test. One reason for wariness given by the FCA was that “the U.K. provision provides explicitly for patent revocation. Section 38.2 does not” [143]. McVeigh J took this as a hint that perhaps invalidity is not a remedy for failure to comply with s 38.2(2), as I did I in my post on that aspect of Western Oilfield, where I said that Locke JA’s statement “raises the question of whether added matter contrary to s 38.2 is a basis for invalidating a claim in a granted patent, or whether it is only ground for refusing an amendment during prosecution.”

On re-reading, I don’t think that is what Locke JA was suggesting. As noted, the discussion was in the context of whether the strict UK test for inferability should be followed. The full paragraph was:

[143] The third reason to be wary of the strict U.K. test is that the U.K. provision provides explicitly for patent revocation. Section 38.2 does not. On the contrary, subsection 38.2(1) provides that, subject to certain limitations, a patent application may be amended. The provision of particular interest in the present appeal, subsection 38.2(2), provides for one of the contemplated limitations.

I think Locke JA’s point is that because an amendment is explicitly permitted, we should be wary of being too restrictive in permitting such amendments. That does not imply that invalidity is not the remedy when the amendment is not permitted, even under a more relaxed test. The FCA in Western Oilfield went on to hold that the amendment was reasonably inferable [147], so the Court did not explicitly address the remedy for failure to comply with this provision.

I’d also note that s 72 of the UK Act exhaustively states the grounds for invalidity of a patent, including that the invention is not patentable (72(1)(a)), which includes anticipation or obviousness, as well as added matter (72(1)(d)). The Canadian Act has no equivalent. Section 60 simply provides that patent may be declared invalid or void, but without listing the specific grounds, and s 59 is the same. And s 28.2, for example, dealing with novelty, only says that subject matter “must not” have been disclosed, but does not say explicitly that a claim may be invalidated on that basis. So, given that there is no provision in the Canadian Act expressly stating that a patent may be held invalid for anticipation, obviousness, inutility or insufficiency, the fact that there is no provision expressly providing that a patent may be held invalid on the basis of 38.2 does mean much. This is another reason for thinking that this comment by Locke JA was not intended to question whether invalidity was the appropriate remedy for failure to comply with 38.2(2).

In any event, while McVeigh J did not consider the matter settled by Western Oilfield, she went on to hold that when an amendment is made in violation of 38.2(2), a claim is indeed invalid [434]. This seems to me to be clearly correct. Suppose I invent the wheel and file an application fully disclosing and claiming the wheel. Then, after I filed, but before my patent is granted, someone else publicly discloses how to make and use mRNA vaccines. I then amend my application to disclose and claim how to make and use mRNA vaccines. My claim can’t possibly be valid, even if it somehow slips through the patent office. There isn’t any other provision that would clearly prohibit this kind of amendment, since the mRNA vaccine is new and non-obvious as of my filing date. Section 38.2(2) provides a straightforward basis for invalidating such a patent.

The issue arose on the facts because of the addition of the phrase “wherein said multiple doses are not subject to any discretionary adjustment by a physician or medical practitioner” to the 917 patent during prosecution, as discussed above. McVeigh J held that amendment did not result in invalidity:

[443] In my view, AbbVie’s addition did not change claim 1, nor does it broaden the claim. Claim 1 would have had the same effect, with or without the additional statement.

[444] However, that is not the issue. The issue is whether the added claim term was reasonably inferable from the 917 Patent disclosure. I find that though it does conflict with the disclosure, AbbVie has not gained anything more than it originally had.

It’s not clear to me what McVeigh J meant when she said the added term “does conflict with the disclosure” but the main point seems to be that since the amendment did not change the claim scope, nothing at all was added, so it follows that nothing that was not reasonably inferable was added.

Claim construction

The only real dispute between the parties was the definition of “treating” in Claim 1

[296] I agree and adopt JAMP’s experts’ construction, as, even given its ordinary meaning, treating does not always achieve a meaningful result. Treating means attaining some therapeutic results but does not demand a particular duration or result.

[297] Treating does not mean achieving a meaningful clinical response and I do not accept Dr. Marshall’s definition that there must be a “certain therapeutic effect” (Dr. Marshall Report at para 91). “Treating” means a physician administering or prescribing adalimumab to an IBD patient according to the dosing regimen of the patent.

This seems right to me, not just on the text.

The question goes to utility. Generally, clinical efficacy does not have to be established at the time of filing. If the research has proceeded to the point where there is sufficient information to support a valid patent, the patent agent will want to draft a valid claim. The drafter will never specify “clinical efficacy” in the claim unless it is crucial to validity, because doing so needlessly raises the bar for utility. It seems to be consistent with a purposive interpretation to construe the claims on the presumption that the drafter did not intend to draft the claim in a way that would undermine its validity.

Allergan v Apotex / Risedronate Dosage Form — Overview

Allergan Inc v Apotex Inc 2022 FC 260 Kane J

2,602,188 / risedronate / ACTONEL DR

This very long decision—262 pages and 946 paragraphs—turns largely on its facts. The length of the decision is a consequence of Kane J’s very thorough recitation of the arguments and evidence. The main point of interest arises from the somewhat unusual claim.

Allergan’s 188 patent relates to a dosage form of a bisphosphonate for use in treating osteoporosis. Bisphosphonates were well known for use in treating osteoporosis. Bisphosphonates were known to have poor bioavailability. One specific known problem was significantly lower absorption when taken with food—the “food effect”. The food effect was thought to be due to bisphosphonates forming complexes with ions, such as calcium and magnesium, from the food in the stomach. (Bisphosphonates were known to be absorbed in the small intestine.) The standard way of addressing the food effect in the prior art was to prescribe the bisphosphonate to be taken while fasting. This gave rise to compliance problems [273].

Allergan came up with a solution to the food effect, namely a dosage form comprising a combination of bisphosphonate with EDTA in an enteric coating. The enteric coating allows everything to pass into the small intestine, where the EDTA—a known chelating agent—binds to the cations and prevents them from binding to the bisphosphonate. This means that the dosage would be equally effective whether given with food or after fasting. Accordingly, Claim 1 of the 188 patent was to “An oral dosage form of a bisphosphonate for use with or without food or beverage intake, comprising...” All the claims incorporated the “for use with or without food” limitation. The “with or without” food structure of the claim is a bit odd, as “or” is normally used to signal alternatives, so that it might have been separated into two claims, one claiming use with food and one without. But given that the purpose of the invention was to overcome the food effect, the experts agreed, and Kane J held, that the claim should be construed to mean that the oral dosage can used “either with food or without food or beverage at the preference of the patient” [228]. That seems right to me.

But there’s a catch. Giving EDTA without food can cause irritation of the esophageal lining. Even though this was apparently an uncommon and fairly minor problem, and did not affect efficacy in treating osteoporosis, the product monograph for Allergan’s product, ACTONEL DR, consequently specified that it should be taken with food. The Apotex PM was essentially identical [905]. Consequently, Kane J held that Apotex’s product did not infringe, either directly or by inducement, because it was not for use with or without food, but only with food [921].

Kane J’s construction seems right, given the phrase “for use with or without food” in the claim. But I am puzzled as to why the patentee included those words in the first place. Kane J said this:

[225] For the ‘188 Patent, the ability to use the oral dosage form either with food or without food is set out in the claim because its purpose is to overcome the food effect (which is the problem of the extremely low absorption of the bisphosphonate when taken with food as opposed to when taken fasted). The oral dosage can be taken either with food or without food at the choice of the patient and the treatment effect will be similar (i.e., pharmaceutically effective absorption). The invention of the ‘188 Patent signalled a significant change in the administration of oral bisphosphonates, hence the emphasis on this feature.

It’s true that the advance was to allow a formulation that can be taken without food as well as with it, and it may be that is what motivated the applicant to include this phrase. But that does not mean that this feature has to be included in the claim itself. (I should note that this explanation was not central to Kane J’s reasoning, as it was not disputed that “with or without food” was an essential element.) So long as the compound itself is new, the purpose need not be specified: if an inventor comes up with a new drug that is useful for curing cancer, they are entitled to claim the compound per se, without restricting it to the use in curing cancer. In this case, the claimed composition* was new: it was essentially a selection over the closest prior art, a prior Brazilian patent application referred to as BR 601: see eg [366], [372]. So I’m at a bit of a loss to explain why it was included.** If the phrase was indeed unnecessary, that suggests the possibility that “for use without or without food” is not an essential element, but this argument was not run by Allergan [188]. So I presume there was some reason for including the phrase that is not apparent from the decision. I wonder if the phrase might have been added to placate an obstinate examiner? I note that even if it was added in response to an objection, it is not clear that this precludes a finding of non-essentiality: see Actavis [2017] UKSC 48 UKSC.

Allegan also argued that “for use with or without food” should be construed as meaning only ‘suitable for’, not intended for. Kane J rejected this argument, which I’ll discuss at more length in my next post.

In light of this construction, infringement turned on the factual issue as to whether the PM instructed use with food, or whether taking with food was optional. Allergan’s argument was to the effect that a skilled person would recognize that it would be effective if taken without food, since the side effects were minor. Nonetheless, as Kane J found [905]–[922], the PM clearly and repeated instructed that the product should be taken with food: eg ““Do not take ACTONEL DR before food or on an empty stomach. . .” That this instruction was to avoid abdominal pain rather than to enable effective absorption does not change the fact that the product was for use with food. Apotex’s PM was the same, and so Apotex did not infringe directly or by inducement.

There are a couple of other points to note. One of the expert witnesses had been ‘blinded’, but Kane J was not impressed: “I note that the jurisprudence is mixed on the treatment of blinded evidence. I favour the approach noted in Janssen Inc v Apotex Inc, 2019 FC 1355 at paras 58-59 . . . that blinded opinions are not necessarily given greater weight just because they are blinded.”

Another point is that the most relevant prior art, a prior Brazilian patent application referred to as BR 601, was obscure prior art; that is, it was available to the public, but it would not have been found by a skilled person in a reasonably diligent search [634]. This raised on the facts the holding in Hospira 2020 FCA 30 that the state of the art for the purposes of an obviousness attack includes all prior art. In my post on Hospira, I suggested that this holding leaves open the question of whether obscure prior art can be mosaiced in an obviousness attack.

Kane J noted that

[635] In accordance with Hospira at para 86, it would be an error for the Court to exclude BR 601 from the mosaic of prior art because it would not be found by the skilled person in a reasonably diligent search.

[636] As guided by Hospira, the likelihood that BR 601 would not turn up (and, based on the evidence, it would not turn up) is relevant to the obvious to try test; i.e., would the skilled person have thought to combine BR 601 with the other prior art to bridge the differences between the state of the art and the invention?

She then noted that

[637] This is a tricky distinction when applied to the facts. If BR 601 is part of the prior art, then the differences between the state of the art and the invention would need to account for whatever can be distilled from BR 601 as part of the “state of the art”. However, if the skilled person would not have found BR 601, how can the skilled person consider it in the context of combining it with other prior art at the obvious to try stage of the analysis of obviousness? This is only possible in circumstances where the unknown prior art is handed to the skilled person. To avoid this dilemma and running afoul of Hospira, I have considered BR 601 as if it were prior art, but as noted, the “teaching” of BR 601 requires careful scrutiny.

Ultimately, Kane J did not have to wrestle too directly with this “tricky distinction”, because, as I read it, BR 601 simply would not make the 188 patent obvious, no matter how it was used. BR 601 was at best a broad genus than encompassed the claimed invention, but did not point to it with any specificity, and did not give any hint of the special advantages of the 188 dosage form.

*The original version of the post said the "compound" was new: that is not correct. It is the claimed composition that was new. 

**Since the composition was new, it seems to me that it could have been claimed as such, without that phrase, in the same way a new compound can be claimed without specifying the use. 

Sequential Unmasking of Expert Witnesses

Amgen Inc v Pfizer Canada ULC 2020 FC 522 Southcott J
            1,341,537 / filgrastim / NEUPOGEN / NIVESTYM

Wednesday’s post gave an overview of the facts and discussed the main substantive holding in this decision, namely that the invention was obvious. The decision also raises sequential instruction of expert witnesses as a way of improving the usefulness of “blinding” the experts.

Southcott J summarized the current law by accepting that “blinding is not a guarantee of reliability. Whether it is a sufficient reason to prefer the evidence of one expert over another depends on the details of the evidence in a particular case. [T]he effect of blinding is a question of relevance, reliability, and weight. It is not a doctrinal matter” [309] (citing 2016 FC 857 [59]).

Southcott J noted that some structural problems may arise that impede effective blinding. For example, effective blinding requires that the expert not have read the patent so as to avoid hindsight bias; but obviousness must be assessed from the perspective of a person skilled in the art to which the patent pertains, and it is necessary to read the patent to determine who the skilled person is.

In this case, Pfizer got around this problem in a manner that met with Southcott J’s approval. Pfizer had one expert read the patent and provide an opinion on the skilled person, and then the second expert was provided with that definition of the skilled person:

[318] This approach demonstrates a potential means of avoiding the concern about blinding creating a structural impediment to experts employing the required tools to formulate their opinions. If one expert provides an opinion defining the Skilled Person after reviewing the relevant patent, that definition can be provided to another expert, who can then give a blinded opinion from the perspective of the Skilled Person without having read the patent or the other experts’ opinions.

Southcott J remarked that while this methodology was not in itself a sufficient reason to prefer Pfizer’s experts over those of Amgen, “blinding is a factor favourable to the reliability of Pfizer’s expert opinions on the work that would flow from [the state of the art]” [320].

This calls to mind the concept of ‘sequential unmasking’ referred to by Arnold LJ in Akebia v Fibrogen [2020] EWHC 866 (Pat):

[36] This submission illustrates why it can be advantageous to try to instruct expert witnesses in sequence, first asking them about the common general knowledge, then showing them the prior art and asking them questions such as what steps would be obvious in the light of it and only then showing them the patent in suit. This is a procedure known as “sequential unmasking” in the psychological literature (see generally on this subject C.T. Robertson and A.S. Kesselheim (eds), Blinding as a Solution to Bias, Academic Press, 2016). The point of it is to try to avoid, or at least reduce, hindsight. In my opinion, it is desirable to try to minimise hindsight on the part of expert witnesses where possible. There is no rule or principle that experts must be instructed sequentially, however.

Arnold LJ went on to note that

[T]here are often real practical problems in doing so. To take just one obvious example, any discussion about the common general knowledge must start by identifying the skilled person or team. How is this to be done if the expert cannot be shown the patent? One way is to ask the expert to make an assumption, which they can check later when they see the patent; but that is not necessarily a perfect solution.

Another, arguably preferable solution to this problem, is that used by Pfizer here, namely providing the second expert with the first’s opinion as to the characteristics of the skilled person.

In any event, it seems that some form of sequential unmasking may be a real advance in terms of allowing experts to provide an effective yet properly blinded opinion.

Presumption That Inventor Intended to Claim the Invention Disclosed?

Seedlings Life Science Ventures, LLC v Pfizer Canada ULC 2020 FC 1 Grammond J
             2,486,935 / Auto-Injection of Medication

Grammond J’s decision in Seedlings v Pfizer raises a number of issues, the most significant of which is the application of overbreadth to hold several claims invalid. This post provides an overview, and discusses Grammond J’s views on “blinding” the expert witnesses, and on the principle that claim construction should be approached “with a judicial anxiety to support a really useful invention.” Subsequent posts will deal with other aspects of the decision.

The invention at issue relates to an auto-injector, primarily intended for injecting epinephrine to treat anaphylaxis. The best known auto-injector is the EpiPen. The original EpiPen was on the market from late 1980s until 2009 [10]. Seedlings’ auto-injector, known as the LifeCard, was the inventor’s solution to problems with the original EpiPen, which he recognized both because of his work as a physician and as a result of his own experience of anaphylactic shock [13]-[14]. The original EpiPen was relatively bulky — a cylinder about 15 cm long and 2.5 cm in diameter — which made it inconvenient to carry. Also, the needle remained exposed after use, which is a particular concern in light of risk of transmission of blood-borne diseases [11]-[12]. The LifeCard is flat and much smaller than the original EpiPen — the size of a thick credit card — so it is more easily carried and used [63]. It also has a shield which moves forward once the injection is complete to protect the needle [19]. (See the video here.)

Pfizer’s allegedly infringing device, referred to as the NGA EpiPen (for “Next Generation Auto-Injector”), is an updated version of the original EpiPen (referred to as the “Legacy” EpiPen). Ultimately, when it came to infringement, Grammond J found that while Seedlings and Pfizer had addressed the same problem, they had come up with different solutions: the NGA EpiPen was oval, not flat [196], and the claims of the 935 patent were not to the concept of a needle shield, but rather a particular method of implementing that shield, and Seedlings’ implementation was different from Pfizer’s.

Blinding the experts
Seedlings “blinded” its experts and asked them to provide their opinion on various issues of claim construction, including the proper interpretation of some claim terms, with little knowledge of the actual dispute and without telling them which party was retaining them [41], [43]. Grammond J shared the skepticism regarding blinding expressed by Locke J 2016 FC 382 [42]–[48] (see here) and Phelan J 2019 FC 1355 [57]–[59], saying “[w]hen courts assess arguments, they focus on the validity of the reasoning, not on the credibility of the person who puts the argument forward. Thus, when assessing expert testimony, the logical character of their reasoning is much more important than the fact that some of them were blinded” [44]. With that said, one of the infringement issues was easily disposed of because Seedlings’ blinded expert had construed the term “flat” in a way that clearly supported Pfizer’s position [196].

Claim Construction
Presumption that disclosed embodiments are claimed
Grammond J noted that presumptions of interpretation are often helpful in claim construction [59]. First, he noted and applied the presumption that the inventor would have intended to claim the embodiments that are disclosed in the specification [58], [70]. “[A]n interpretation of the claims that would exclude the embodiment shown in the drawings or described in the specification is suspect, as it is unlikely to reflect the inventor’s intention,” (citing 2016 FC 580 [335]). Note that Grammond J’s application of the rule made it clear that this presumption applies to any embodiment that is disclosed in the specification, not just the preferred embodiment: see also [2009] EWHC 55 (Pat) [92].

Presumption that claims should be interpreted to preserve validity?

On the other hand, Grammond J rejected Seedlings’ argument that there is a presumption “that patents should be interpreted in a way that ensures their validity” [59]. That proposition was based on the statement by the SCC in Consolboard [1981] 1 SCR 504, 521, quoting with apparent approval Sir George Jessel’s statement in Hinks & Son v Safety Lighting Co (1876) 4 ChD 607, that “the patent should be approached ‘with a judicial anxiety to support a really useful invention’.” Grammond J noted that this statement seems to be in tension with the SCC’s statement in Whirlpool 2000 SCC 67 [49a] that “[a] patent must not of course be construed with an eye on the allegedly infringing device in respect of infringement or with an eye to the prior art in respect of validity to avoid its effect.” Grammond J suggested that “the reference to ‘judicial anxiety’ appears to relate to the idea that a patent should not be invalidated on a technicality,” [59] citing Burton Parsons [1976] 1 SCR 555, 563. While it is certainly true that a patent should not be invalidated on a technicality, as Burton Parsons states, I doubt this is all that the SCC had in mind in Consolboard, where the Court explained that “where the language of the specification, upon a reasonable view of it, can be so read as to afford the inventor protection for that which he has actually in good faith invented, the court, as a rule, will endeavour to give effect to that construction” (quoting with approval Western Electric Co v Baldwin Int’l Radio [1934] SCR 570, 574). This seems to say something more than merely disfavouring technical attacks.

I suggest that a way to reconcile Consolboard and Whirlpool is to consider Consolboard as stating a presumption that the patentee intended to claim the inventive concept that was disclosed in the specification. This is very similar to the presumption that the patentee intended to claim the specific embodiments that were disclosed, except it looks to the inventive contribution, rather than the embodiments. As the Supreme Court pointed out in Whirlpool [37] “the bargain between the patentee and the public is in the interest of both sides only if the patent owner acquires real protection in exchange for disclosure.” An inventor who has disclosed a new and useful invention and who frames a claim that is too broad or otherwise invalid receives nothing in return for their valuable disclosure. Conversely, a claim that is too narrow will be valid, but will deprive the inventor of the bulk of his due reward: see Burton Parsons at 565. A presumption that the inventor intended to claim the invention that they disclosed is no less consistent with Whirlpool, that is the presumption that the inventor intended to claim the embodiments that were disclosed. It also seems to be a realistic reflection of the inventor’s intent, and not a mere legal fiction. As Buckley LJ pointed out in the EWCA in Catnic [1982] RPC 183, 227, “An applicant for a patent will want his leading claim to be as wide as is possible consistently with its validity. He will wish to avoid any unnecessary restriction of it.”

More Support for Experimental Use Exception to Anticipation

Hospira Healthcare Corporation v. Kennedy Trust for Rheumatology Research 2018 FC 259 Phelan J
            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.

Specific v General Motivation in the Obviousness Analysis

AstraZeneca Canada Inc. v. Mylan Pharmaceuticals ULC 2017 FC 142 Diner J
            2,449,098 / naproxen-esomeprazole dosage form / VIMOVO / NOC

In this decision Diner J held AstraZeneca’s 098 patent to be invalid for obviousness, relying in part on the obvious-to-try analysis set out in Sanofi 2008 SCC 61. The decision turned essentially entirely on the facts. There were a few legal points of some interest, the most notable being the discussion of the distinction between specific and general motivation in the obviousness analysis. More broadly, I must admit that I did not find the obvious-to-try analysis as set out in Sanofi itself to be pellucid, but the Federal Courts have nonetheless consistently applied it in a robust and principled manner to invalidate patents for invention which were the result of routine testing of alternatives that was more or less guaranteed to arrive at a solution to the problem at hand, even if the precise solution could not have been predicted in advance.

Before turning to obviousness, there are a couple of other issues worth mentioning. As discussed here, there has been an ongoing debate as to whether recourse to the disclosure as an aid to construing the claims is always permissible, or is permissible only if the claims are ambiguous on their face. While claim construction was not particularly controversial in this case [28], and Diner J did not address the debate directly, he provided the following summary of the law (citations omitted):

[26] In sum, a patent is to be construed through the eyes of the POSITA having a mind willing to understand the invention, and the claims are to be approached in a purposive manner and construed in light of both the disclosure and the claims. That said, while it is permissible to read the disclosure in order to assist in understanding the terms used in the claims, the disclosure cannot be used to construe the claims more narrowly or widely than the text of the claims allows

This strikes me as both sensible and an accurate summary of the law.

The issue of blinding the experts also arose. Mylan argued its experts should be preferred because they were blinded to the NOA, and AstraZeneca responded that Mylan’s experts should be ignored because they failed to address the NOA [74], [76]. Diner J stated that “Blinding experts does not necessarily produce a more reliable outcome” [77]:

[78] In this case, the approach of both sides in the preparation of their witnesses was acceptable, and as a result neither warrants exclusion or less weight. Rather, my analysis turns on which of the experts provided the most compelling evaluations of the common general knowledge held by the POSITA, the state of the art, and other factors in the obviousness analysis.

While the debate over blinding is not over yet, and no doubt is will continue to be a helpful practice in some situations, Diner J’s remarks seem to me to reflect and reinforce a trend towards not putting too much weight on the question of blinding.

The key substantive issue was obviousness. Naproxen was a known NSAID, and like other NSAIDs it can cause gastrointestinal [GI] injuries if taken alone [5]. Various mitigating strategies were known, including co-administration with a PPI [6], but co-therapy was known to have patient compliance problems [7]. The asserted claims of the 098 patent solved this problem with a sequential release tablet comprising esomeprazole, a PPI, in immediate release form (not surrounded by an enteric coating), with a delayed release of naproxen, an NSAID [107]. The parties largely agreed that the difference between that inventive concept and the state of the art was the sequential release profile, which was achieved by the decision not to fully enteric coat the PPI [113]. This was arguably inventive, because PPIs were sensitive to acid, so that it was common practice to enteric coat PPIs [46]. After a review of the facts, including consideration of the obvious-to-try factors, Diner J found the difference between the invention and the state of the art to be obvious [130], [171]. This holding turned largely on the facts, but one statement of law is worth quoting, as it reflects a common thread through the Federal Court’s obvious-to-try decision:

[134] Furthermore, neither the fact that (i) no one knew whether the claimed invention would provide any additional benefit (i.e. the non-enteric coated PPI), nor that (ii) there were other options amongst gastroprotective agents apart from PPIs, render the claims non-obvious. The following words of Justice Barnes in Janssen Inc v Teva Canada Limited, 2015 FC 184 at para 113, are apposite:

…The fact that the formulator had a few choices to make and would need to test the formulation to ensure its efficacy does not render this exercise non-obvious. Here I adopt the point made by Justice Roger Hughes in Shire Biochem Inc. v. Canada (Minister of Health), 2008 FC 538 (F.C.) at para 80, [2008] F.C.J. No. 690 (F.C.), that the existence of number of possible routes to solve a problem does not mean that the route taken was not obvious. In Brugger v. Medicaid Ltd. (No. 2), [1996] R.P.C. 635 (England P.C.) at p 661, the same point was stated in the following way:

First a route may still be an obvious one to try even if it is not possible to be sure that taking it will produce success, or sufficient success to make it commercially worthwhile. ... Secondly, if a particular route is an obvious one to take or try, it is not rendered any less obvious from a technical point of view merely because there are a number, and perhaps a large number, of other obvious routes as well. If a number of obvious routes exist it is more

Finally, Diner J’s discussion included a fairly extensive discussion of the significance of general vs specific motivation in the obviousness analysis [148ff]. AstraZeneca seems to have argued that the invention would not be obvious unless the POSITA would have had a specific motivation to come up with the particular inventive concept of the 098 patent [140], while Mylan argued that specific motivation is not required [150]. Diner J agreed with Mylan [150].

Diner J suggests that a “general” versus “specific” motivation distinction “may be a false dichotomy” [152]. He made two suggestions. First, “the measure to be taken is one of difference or degree, not kind. Like with many subjective measures, the notional skilled person’s motivation would at best be identified as somewhere along a spectrum” [153]. This means it would be confusing rather than helpful to require a binary determination[154].

Diner J also had a second suggestion:

[159] [S]pecific motivation arguably cuts both ways. It could be said that its existence indicates that it was likely obvious that someone would eventually get there, without inventiveness. On the other hand, it could be said that the existence of specific motivation before the claimed invention was patented only reinforces Beloit’s classic question (at para 21): if it was obvious – and there was specific motivation to try it – why didn’t you?

Similarly, in Janssen-Ortho 2007 FCA 217 [25.5], the FCA suggests that general motivation is important because if there has been a long-standing general motivation to solve a problem, and no one has been able to do so, this is evidence that the solution someone finally does come up with was not obvious. On the other hand, if there wasn’t any general motivation to solve a problem, then the answer to Beloit’s classic question may be “no one bothered to try.” This suggests that even if motivation were a binary question, “[i]ts relative importance will depend on the context and factual backdrop of each case” [151]. Again, this leads to the conclusion that a distinction between general and specific motivation is a false dichotomy. That does not mean that general and specific motivations are the same, but rather than the effect of motivation on the obviousness analysis depends on how it interacts with the other relevant facts, and not which category it falls into.

Broad Experimental Use Exception to Anticipation

Bayer Inc v Apotex Inc 2016 FC 1013 Fothergill J
            2,382,426 / micronized drospirenone / YAZ YASMIN / action

Bayer’s ‘426 patent covers an oral contraceptive comprising drospirenone and ethinylestradiol, where the drospirenone is in the form of fast dissolving particles. In this consolidated infringement action, Fothergill J found claims 31, 48 and 49 to be valid and infringed by Apotex’s Zamine and Mya tablets and Cobalt’s Zarah tablets. The conclusions on validity and infringement turned on almost entirely the facts. With that said, it is significant that that Fothergill J accepted the broad experimental use exception to anticipation set out by Hughes J in his NOC decision concerning the same patent. Fothergill J’s remarks on blinding of expert witnesses, as well as on comity and the binding effect of prior FCA decisions on claim construction, are also of interest. This post deals with experimental use and blinding, while tomorrow’s post will deal with comity.

More than one year before the filing date, Schering, Bayer’s predecessor in title [19], conducted Phase III clinical studies in Europe and the United States involving oral contraceptive tablets containing the claimed amounts of drospirenone and ethinylestradiol [145]. (It is not clear to me whether it was admitted that these tablets also fit the claimed formulation profile, but for the purposes of Fothergill J’s reasoning, we may assume they did.)

Participants were given a large number of the tablets, which were to be self-administered over several months outside of a clinical setting. In all three trials, participants were told what the tablets contained, and knew that the tablets were intended to be used as oral contraceptives. No restriction was imposed on participants regarding the disclosure of information concerning the tablets. The participants did not sign confidentiality agreements. [145-46].

Apotex alleged these trials anticipated the ‘426 patent. Fothergill J held they did not. He pointed out that anticipation requires enabling disclosure, and he held that even if some of the tablets had made their way into the hands of a person skilled in the art, such a person would not have been able to reverse engineer the tablets to discover the particular formulation which constituted the invention without the exercise of inventive ingenuity [154-55]. That finding turned on the facts and the law he applied is not controversial.

More interesting is the “alternative” basis for Fothergill J’s holding that the trial did not anticipate [156]. In Bayer v Apotex 2014 FC 436 a prior NOC case involving the ‘426 patent, the same argument was raised that these same clinical trial were anticipatory. Hughes J held that they were not, on the primary basis that Bayer benefited from an experimental use exception to anticipation. The following key passage from Hughes J's decision was quoted by Fothergill J [159]:

[121] In the present case clinical studies were necessary to prove that the drug was safe and effective and, thereby, gain government approval for sale. Until this had been demonstrated, no commercial sale of the drug could have been made. Bayer took reasonable steps to ensure the confidentiality of the relevant documents and to ensure that unused tablets were returned. The theoretical possibility that some tablets were retained and analyzed is just that, theoretical. This theoretical possibility does not preclude the fact that the studies were experimental, and of necessity, conducted by the provision of tablets to members of the public. Thus these clinical studies are exempted from public use.

As I said in my blog post on Hughes J’s decision, this seemingly establishes a broad experimental use exception to what would otherwise be anticipating disclosure, which applies to any clinical trial, so long as reasonable steps are taken to ensure that the unused tablets are returned. Fothergill J agreed with Hughes J both as to this statement of the law and its application to the facts of this case [156], [159]. Fothergill J also clarified that the fact that these trials had been conducted for the purpose of gaining regulatory approval did not take them outside of the experimental use exception [162].

In my post on Hughes J’s decision, I suggested that his decision was notable because, while there was some case law supporting such a broad exception, it was not well-established. Fothergill J’s holding is therefore significant as reinforcing the law stated by Hughes J.

Blinding Expert Witnesses
Apotex argued that the evidence of its expert witnesses should be preferred to those of Bayer’s witnesses because its experts had been “blinded.” Like Brown J in the recent VIREAD decision, 2016 FC 857 (blogged here), Fothergill J was unimpressed by the arguments in favour of blinding. Fothergill J noted that “[t]he fact that expert witnesses were blinded may be persuasive and helpful in weighing their evidence where credibility concerns arise” [65], but, citing Locke J in Shire 2016 FC 382, [45] (blogged here), he continued to say that “if an expert’s opinion is well supported, then there may be no reason to place less weight on the expert’s evidence merely because he or she was not blinded to certain facts when forming that opinion” [66]. In this case, “I have not found the blinding of expert witnesses to be a significant factor in deciding the legal and factual issues raised by this case” [66]. It is still too early to be sure, but the tide may be turning against “blinding.”

VIREAD Patent Valid on the Facts

Gilead Sciences v Apotex Inc 2016 FC 857 Brown J
            2,261,619 / tenofovir disoproxil / VIREAD / NOC

In this NOC decision. Apotex’s validity attacks on the ‘619 patent, based on anticipation / invalid selection, obviousness and lack of utility, all failed on the facts. The main point of legal interest is Brown J’s agnostic approach to the question of “blinding the witness.”

Tenofovir, or PMPA, is a nucleotide reverse transcriptase inhibitor which was known to be effective against retroviral infections such as HIV. However, its oral bioavailability was poor and it was only effective when administered intravenously [32]. The claim of the ‘619 patent at issue, Claim 32, claims tenofovir disoproxil (TD) and its salts, tautomers and solvates [6], [70]. TD is an oral prodrug of tenofovir, which allows effective oral admininstration of tenofovir [31].

Another Twist on Blinding the Expert

Bristol-Myers Squibb v Teva 2016 FC 580 Mactavish J
            2,250,840 / 2,317,736 / atazanavir / REYATAZ

In a number of recent cases (see here), the parties have tried “blinding” their experts from certain facts in a laudable attempt to reduce the problem of hindsight bias. The Atazanavir decision raised another twist on this practice, which is this subject of today's post. For an overview of the facts, see this post, which also discusses some of the issues related to obviousness; and see this post discussing claim construction.

The point arose in the context of the 840 patent, which claims atazanavir. One of Teva’s experts on obviousness, Dr Romero, was blinded perhaps even more thoroughly than in most previous cases:

[192] Dr. Romero was not told the name of the drug that was at issue in this proceeding, other than the fact that it was a protease inhibitor, nor was she told the names of the parties. She was also asked not to carry out any independent research that might identify the drug in question.

That is, it seems that Teva tried to place Dr Romero in the place of the notional skilled person, trying to solve the problem facing the inventors, without knowledge of their solution. There are a couple of caveats even to this degree of blinding. One is that an expert like Dr Romero cannot forget her own current knowledge, and to the extent that she is familiar with approaches that would not have been common knowledge at the time, she cannot fully avoid the effects of hindsight, even when blinded to the particular facts. Also, as Mactavish J pointed out, “Dr. Romero was provided with a limited selection of the prior art that had been ‘cherry-picked’ by Teva, and her evidence has to be viewed with this in mind” [193]. This point was not merely theoretical; Mactavish J expressed concern that Dr Romero had only been provided with papers dealing with an azapeptide backbone, the class which atazanavir belongs to, and not prior art dealing with other possible backbones [194].

With those caveats, no approach is perfect and this heightened degree of blinding seems to be helpful in avoiding hindsight bias. However, it did not help Teva win its case. The details of Dr Romero's evidence were not spelled out by Mactavish J, but it seems the gist was that there were a finite number of modifications that the POSITA would have made in trying to make a better protease inhibitor [212]. However, Dr Romero proposed some modifications to the backbone which would never have led to atazanavir [195], and

[211] Dr. Romero does not identify which compounds or which substitutions should be made to obtain an improved protease inhibitor in her evidence, or how the POSITA should prioritize them. Importantly, Dr. Romero never states that the POSITA would make the substitutions necessary to get to atazanavir.

In the end, Dr Romero’s evidence may have hurt Teva’s case as much as it helped. The 840 patent survived the obviousness attack, and was ultimately held to be valid.

The fact that blinding the expert did not help Teva in this case helps confirm the value of the practice. If a witness blinded in this manner had arrived directly at the claimed invention, it would seem to be good evidence that the invention was obvious. (Though even this degree of blinding would not be conclusive, in light of the caveats noted above, as well as Locke J’s observation in 2016 FC 382 [46].)