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.