Obvious to Try Does Not Require That it Is Obvious That What Is Being Tested Will Work

Hospira Healthcare Corporation v. Kennedy Trust for Rheumatology Research 2020 FCA 30 Locke JA: Rivoalen, Nadon JJA var’g 2018 FC 259 Phelan J
            2,261,630 / infliximab / INFLECTRA

There is some confusion in the obvious-to-try test as discussed in Sanofi 2008 SCC 61. At one point the SCC stated that

[65] I am of the opinion that the “obvious to try” test will work only where it is very plain or, to use the words of Jacob L.J., more or less self-evident that what is being tested ought to work.

This lends itself to the view that it must be self-evident, prior to any experimentation, that the claimed invention will solve the problem at hand. But there is a second understanding of the obvious-to-try test that emerges from the very next paragraph, where the SCC went on to say (my emphasis):

[66] For a finding that an invention was “obvious to try”, there must be evidence to convince a judge on a balance of probabilities that it was more or less self-evident to try to obtain the invention. Mere possibility that something might turn up is not enough.

This implies that it must be more or less self-evident to try, not more or less self-evident that what is being tried will work.

In my view, the latter interpretation is preferable. As the SCC noted at [68], the obvious to try test is appropriate “[i]n areas of endeavour where advances are often won by experimentation.” In such fields, a test requiring that it is very plain, prior to any experimentation, that the invention would work, would mean almost nothing would be obvious. On the second interpretation of Sanofi, if something is obvious to try, and when tried, it works without difficulty, there is no inventive ingenuity involved in arriving at the invention, even though the result could not have been predicted in advance. So, if a routine salt screen discloses that the maleate salt of a new pharmaceutical has good manufacturability, that might not support a patent to the maleate, even though it could not have been predicted in advance that the maleate would be better than any other pharmaceutically acceptable salt.

As I have discussed in previous posts (here and generally here), the Federal Court has quite consistently applied the second approach to the obvious-to-try test, under which an invention might be considered obvious even though a successful outcome could not have been predicted in advance.

In this case, Phelan J appeared at some points to apply the first approach, saying that “Although the POSITA may have had “good reason” to pursue the combination of anti-TNF-α and MTX, it was not self-evident that this combination would work to solve the problem identified in the prior art” [226] (and see similarly 228].) The FCA disapproved of this statement, with Locke JA saying at [94]:

[T]his factor is not determinative. The other factors also required consideration. In my view, the Judge’s analysis of the second factor (concerning the extent, nature and amount of effort required to achieve the invention) was inadequate.

This means that the mere fact that a successful outcome could not have been predicted in advance does not mean that the invention is not obvious under the obvious-to-try test. This is a welcome affirmation from the FCA that the second approach to the obvious-to-try test that I have outlined above is indeed preferable.

However, the FCA went on to say (my emphasis) that:

[95] The determinative test on this issue is whether it was more or less self-evident to try to obtain the invention, including co-administration of an anti-TNF-α antibody and MTX to treat RA in MTX IRs.

This implies that if an invention was obvious to try, it will necessarily be obvious under the obvious to try test. The statement that this is the "definitive test" is difficult to reconcile with the SCC’s statement in Sanofi at [64] that ”the ‘obvious to try’ test must be approached cautiously. It is only one factor to assist in the obviousness inquiry.” Similarly, the SCC remarked that "obvious to try” is “not a mandatory test,” but rather “one factor of a number that should be considered, having regard to the context and the nature of the invention” [62]. So, I would suggest that if a particular avenue is obvious to try, and it eventually succeeds, but only after prolonged and difficult experimentation, it may well be inventive even though it was obvious to try. [Update: On re-reading, I think that Locke JA meant only that this was the determinative test on the facts of this case, not that it is the determinative test generally.] 

On the facts, I would note that while at places Phelan J did indicate that the invention was not obvious to try simply because it was not self-evident that it would succeed, other statements can be taken to imply it was not obvious even to try (see esp [223]).

Both Phelan J [24] and Locke JA [15] remarked on the vast array of issues raised by Hospira, to the extent that Locke JA stated that “it will not be practical to address each one specifically” [15]. I can only suppose that as a consequence, the submissions weren’t as fully prepared as they would have been if the arguments had been more carefully focused, and I can’t help but feel that this is reflected in the reasons.