“Obvious-to-try” and “Obvious to Try”

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

In this NOC action, Southcott J found Amgen’s 537 patent to be obvious on an obvious-to-try analysis in a decision that turned almost entirely on the facts. The patent at issue is governed by the old Act [10]; it was filed in 1986, claiming priority from an August 1985 US application, and was issued in 2007 – more than twenty years after its priority date. This in itself illustrates a glaring deficiency of the old Act; if the 537 had been valid, it would be unconscionable if a 35 year old invention could be used to impede current drug development.

The patent relates to a filgrastim, a hematopoietic growth factor, which stimulates the growth of white blood cells [11]. It is used to boost the immune system in cancer patients whose natural immune system has been compromised by chemotherapy [149]. Filgrastim is a recombinant DNA version of the naturally occurring “granulocyte colony-stimulating factor” or “G-CSF” [12]. The key moment in the development of filgrastim was the discovery by scientists at the Sloan-Kettering Institute that a protein secreted by a certain human bladder carcinoma cell line had a stimulatory effect on blood cell precursors. This work was published by Welte in March 1985 [24]. The Amgen scientists built on Welte by identifying and sequencing the associated gene and using recombinant DNA technology to express it in a host cell to allow production of clinically useful quantities of G-CSF [25]. It was largely uncontested that it was obvious to try making a recombinant G-CSF in light of Welte, and the real question was whether there was any inventive step required to actually do so. Southcott J ultimately held that the path forward was known at the time, and there were no hurdles that required inventive ingenuity to surmount.

I have little doubt that if, instead of publishing, Welte et al had developed their discovery into a recombinant G-CSF, their invention would have been patentable, with the inventive step lying in the identification of the naturally occurring protein and its properties. On the other hand, while the work done by Amgen was, in one sense, routine, it may be doubtful whether any institution would have actually carried it out without the lure of a patent. Thus the broad underlying issue strikes me as a version of the problem addressed by the Bayh-Dole Act; even if the true inventive step is undertaken at a university research lab, or some similar institution, and introduced into the public domain, some kind of IP rights may nonetheless be needed to incentivise the additional steps needed for commercialization. In principle that incentive may be provided by data exclusivity; in any event, a monopoly on products produced 35 years later is clearly not the right solution.

Doctrinally, Southcott J’s decision strikes me as a careful application of the obvious-to-try analysis. At the risk of sounding like a broken record, I’ll recapitulate my views on the obvious-to-try test, and show how Southcott J’s analysis is a good example. It’s a bit unfortunate that “obvious-to-try” has become the name of a doctrine, as opposed to a string of words with their ordinary meaning. I will distinguish “obvious-to-try” as the doctrine, from “obvious to try” as words with the ordinary meaning that it was obvious to try whatever it was, without any implication that the invention was obvious or not.

While “inventive step” and “obvious” are two sides of the same coin, the analysis is much easier if we approach it in terms of inventiveness. There are two questions: (1) Was it inventive to think of even trying the claimed invention as a solution to the problem at hand? If yes, then it was inventive, regardless of how easy it was to implement the solution: see eg Tye-Sil (1991) 35 CPR(3d) 350 (FCA). If the answer to (1) is no (ie it was obvious to try), then (2) was there an inventive step in achieving success? If the answer to (2) is yes, then invention is not obvious, regardless of how easy it was to think of trying it in the first place. If the answer to both these questions is no — it was not inventive to try and there was no invention in achieving success — then there was no inventive step anywhere along the path, which is to say that the invention was obvious. I acknowledge that this is not the way the “test” was laid out in Sanofi 2008 SCC 61, [69], but I suggest it is consistent with Sanofi.

Southcott J identified three “factors” from Sanofi [69]: namely Motive [291ff]; whether it was self-evident that what being tried ought to work (Self-Evident Factor) [296ff]; and Extent of the Effort [367ff]. The Motive factor goes to the first question, whether it was obvious to try the invention. It was not really contested that there was specific motivation in 1985 to make a recombinant G-CSF in light of Welte. While Southcott J remarked that “the Motive Factor is only one factor and is not determinative” [296], he later [322] invoked the statement by the FCA in Hospira FCA, 2020 FCA 30 [90] that (my emphasis):

It should be noted that, whereas being “more or less self-evident to try to obtain the invention” (per Sanofi at para. 66) is a requirement for obviousness to try, being “more or less self-evident that what is being tried ought to work” (per Sanofi at para. 69) is not a requirement but merely a factor to be considered.

I have to admit that I overlooked this paragraph in my post on Hospira, but I now see its importance in establishing that the three factors — Motive, Self-Evident and Extent of the Effort — should not be seen as three factors going into the same hopper to be blended together: Motive is a requirement, while Self-Evident is not.

This makes sense in light of the two-step approach outlined above. The first phrase in the statement by the FCA is to the effect that if it is not “more or less self-evident to try to obtain the invention,” then the invention is not obvious. This goes to question (1): if there was an inventive step involved in the decision to try the claimed invention, then the invention is not obvious; that is why being more or less self-evident to try is a requirement for obviousness. So, keeping in mind the distinction between “obvious-to-try” and “obvious to try,” we can say that if the invention is not obvious to try, then it is not obvious-to-try, which means it is not obvious.

But the converse is not true; simply because an invention is obvious to try, does not mean it is obvious-to-try; we have to go on to question (2) and look at the other factors to see whether there was an inventive step involved in achieving success. This is why, as the FCA noted, the Self-Evident factor is not a requirement. Accordingly, Southcott J treated the Self-Evident Factor and the Extent of Effort Factor as distinct factors, neither of which is determinative. It may be that it is more or less self-evident that what is being tried ought to work, given expenditure of sufficient effort and resources, and yet at the same time, “the experimentation prolonged and arduous, such that the trials would not be considered routine” Sanofi [69]; and see similarly Halocarbon [1979] 2 SCR 929, 944: "A patient searcher is as much entitled to the benefits of a monopoly as someone who hits upon an invention by some lucky chance or inspiration".

On the facts, Southcott J’s conclusion on the Self-Evident factor is that it would be self-evident that the steps leading to the claimed invention polypeptide ought to work [366]. On the Extent of Effort, he concluded that “Any potential challenges [the skilled person] would encounter could be addressed with skill and did not require inventiveness” [425]. I like this way of putting it because he phrases it in terms of inventiveness, which I find more intuitive in this context. Putting these together, (1) there was no inventive step in the decision to try the claimed invention — it was obvious to try; and (2) there was no inventiveness required in achieving success — it was (i) self-evident that it would work (ii) without undue effort; and therefore the invention was obvious-to-try and therefore obvious.