Promise Doctrine Applied

Bristol-Myers Squibb Canada v Apotex Inc 2017 FC 296 Manson J
            2,366,932 / 2,519,898 / dasatinib / SPRYCEL / NOC

Apotex sought an NOC for APO-Dasatinib, using BMS’ SPRYCEL as the Canadian reference product [3]. In response, BMS sought an order of prohibition based on the 932 and 898 patents, both of which are related to dasatinib [2]. Manson J held the 932 patent to be invalid for lack of sound prediction of utility, in reasons which don’t make any new law, but which do demonstrate the continued impact of the promise doctrine. He also held the 898 patent to be invalid as being obvious-to-try and for double patenting. The obvious-to-try aspect of the decision turned on the facts, but there were a couple of legal points of passing interest. I’ll address double-patenting in a subsequent post.

Dasatinib is used to treat a form of chronic myelogenous leukemia (“CML”). Claim 27 of the 932 patent, the only independent claim at issue [52], claims the compound dasatinib [75], while various uses of dasatinib are claimed by dependent claims [55]. Claim 27 of the 932 patent was held invalid for lack of sound prediction of utility, but this result was driven by the analysis of the promise of the patent. As is normal in disputes over the promise of the patent, the patentee argued for a relatively modest patent, and the generic argued for a more demanding promise. In this case, Manson J adopted the promise proposed by the expert for Apotex, which required, inter alia, that the compounds were therapeutically useful [97]. The patentee did not dispute that there was no sound prediction of therapeutic utility for dasatinib at the claim date [99], and so the finding of lack of sound prediction followed directly from the construction of the promise of the patent. The main point of general interest is that Manson J distinguished Apotex Imatinib 2013 FC 141 (blogged here), on the followin basis (my emphasis):

[95] In the ‘932 Patent, the language used in the specification is not equivocal in the same manner as the Apotex Imatinib patent (i.e., “can be used”). There are numerous instances in the Utility section where the inventors have stated that the compounds “are” useful for treatment of disease.

In other words, in describing the uses of the invention, the word “are” can sink your patent, while the words “can be used” may save it, notwithstanding that the information communicated to the public is substantively the same. This type of “meticulous verbal analysis,” of the type disparaged in Catnic [1982] RPC 183, 243 (HL) is now entrenched in our law, unless and until the SCC addresses the promise doctrine in its forthcoming NEXIUM decision.

Turning to the 898 patent, the only claims at issue were to the oral use of dasatinib for treating imatinib-resistant CML (Claims 1 and 3, respectively) [126]. While both parties agreed that it was not obvious at the relevant date that dasatinib would be an effective oral treatment for these purposes[173], Manson J agreed with Apotex that it would have been obvious to try [186], [202]. This holding turned on the factual finding that the work needed to arrive at the invention was routine, in light of the relevant prior art.

Two points made in passing are of some interest. First, there was a dispute as to whether two patent applications that would have been publically available before the relevant date for assessing obviousness [151], were part of the prior art. In ruling that they were, Manson J stated that “The Federal Court of Appeal has held that prior art relevant for the purposes of assessing obviousness is limited to that which the POSITA “would locate conducting a reasonably diligent search” (E Mishan & Sons Inc v Supertek Canada Inc, 2015 FCA 163)” [154]. I’m not sure that is quite right; it is more accurate to say, as Locke J said in Pollard Banknote 2016 FC 883, [193], that the FCA “declined an opportunity to revisit the question,” whether it was so limited: see here. With that said, it didn’t make any difference in this case, because the immediate question was whether Apotex was limited to prior art found by its experts, or could also consider prior art found by the respondent. Manson J’s real holding was that “while it may be best practice when asking experts to opine on prior art or the common general knowledge to have them perform the necessary searches, the NOC process can constrain a respondent, who must ensure that all facts that they will rely upon at trial are part of the NOA; therefore, a respondent is likely to have curated the prior art before hiring experts” [154].

Secondly, Manson J also held, rightly, in my view that “[t]he fact that there are multiple obvious routes towards an invention does not necessarily render any or all of them all non-obvious,” noting that “[t]his is particularly true given the methods through which scientists screen compounds for potential therapeutic activity” [196].