Thursday, April 12, 2012


I will be grading exams from now until I take an end of term vacation starting next week, so I will not be able to read any cases for the rest of the month. I'll be blogging again around May 4th or 5th 9th or 10th, starting with the cases that I missed in the interim.

Thursday, April 5, 2012

A Shift in Approach to the Promise of the Patent?

Mylan Pharmaceuticals ULC v. Pfizer Canada Inc. / donepezil (NOC) 2012 FCA 103 Mainville JA: Sharlow, Gauthier JJA aff’g 2011 FC 547 Hughes J (ARICEPT, Pat No 1,338,808)

I wrote Tuesday’s post on this decision in a bit of a hurry, as I heading to Ottawa for the Symposium on Utility Requirements: Converging and Diverging Approaches, and there are a couple of points that deserve more attention than I gave them. (The Syposium was a great success – the papers and presentations are available here.)

As I noted in Tuesday’s post, the FCA distinguished its decision in Pfizer / latanoprost 2011 FCA 236. That decision was very problematic because of its unprincipled approach to the construction of the promise of the patent. This point may deserve more emphasis than I gave it. There are a couple of paragraphs from Pfizer / donepezil worth quoting in full:

[56] The patent in Latanoprost claimed a “therapeutic composition for topical treatment of glaucoma or ocular hypertension, containing a prostaglandin…in an amount sufficient to reduce intraocular pressure without causing substantial ocular irritation…”: Latanoprost at para. 8 [emphasis added]. In this unique circumstance, where the patent appeared to be premised on avoiding the disadvantage associated with side effects, this Court construed the patent considered in Latanoprost as promising the avoidance of side effects. In contrast, claim 18 of the ‘808 Patent simply refers to a “ therapeutical composition for treating senile dementia…” without any further promise relating to side effects or toxicity. There is no relation between the ‘808 Patent and the patent reviewed in Latanoprost . The ‘808 Patent is rather akin to the patent reviewed by the Supreme Court of Canada in Wellcome.

To my mind, this is not a particularly convincing distinction, as it was an express object of the ‘808 patent, at issue in Pfizer / donepezilto develop a drug “which has a persistent activity and a high safety” (disclosure p2, quoted 2011 FC 547 [232]. This and the “unique circumstance” language, suggests that the FCA in Pfizer / donepezil was not so much distinguishing Pfizer / latanoprost, as indicating it was wrongly decided, without saying so directly. Also, as Tony Creber pointed out to me when we spoke about this decision at yesterday’s symposium, it is interesting that the FCA is focusing on the language of the claim, since construction of the promise has typically focused on the description. While this passage certainly does not say that the description should be ignored in construing the promise, even a heightened role for the claim would mark a major shift in this doctrine. (Indeed, an exclusive focus on the claims might mark the end of the doctrine in many contexts; for example, no promise could be extracted from a claim to a compound per se. But we are still far from that point.)

Both of these points are reinforced by the next paragraph:

[57] Though some references are made in the ‘808 Patent to potential toxicity and efficacy benefits of donepezil, and to its potential advantages over prior art compounds, the application judge, on the basis of the expert evidence before him, rightly concluded that these references are not to be construed as promises. He noted that the use of the specification of a patent in order to construe its promise “is not to serve as an invitation to a zealous lawyer to read a patent specification in such a way as to persuade a Court, one way or the other, as to what the promise is”: Reasons at para. 213. As recently aptly noted by Zinn J. of the Federal Court, “the jurisprudence does not permit an unescorted and unchaperoned romp through the disclosure”: Janssen-Ortho Inc. v. Canada (Health) , 2010 FC 42, 82 C.P.R. (4th) 336 at paras. 119-120. The disclosure in the specification is to be understood from the viewpoint of a skilled person in the art or science to which the invention pertains, without resort to technicalities but rather for the purpose of seeking a construction of the claims which is reasonable and fair for both the patentee and the public: Consolboard Inc. v. MacMillan Bloedel (Sask.) Ltd. , [1981] 1 S.C.R. 504 at pp. 520-21.

This paragraph does not expressly change the law, but it is a clear signal that the FCA – or at least this particular panel – is aware of the problems of unpredictability caused by the ad hoc nature of the false promise doctrine. It could also be taken as a message to the Federal Court to be less aggressive in the using the doctrine to impose a heightened utility requirement on patentees.

It is too soon to be sure, but it may be that Pfizer / latanoprost marked the high water mark in the aggressive application of the false promise doctrine, and that Pfizer / donepezil will turn out to be a turning point. I wonder if the extreme nature of the FCA decision in Pfizer / latanoprost may have been a blessing in disguise for pharma patentees, as it may have alerted the FCA as a whole to the problems created by the false promise doctrine.

Tuesday, April 3, 2012

Pfizer / Latanoprost Distinguished on Interpreting the Promise of the Patent

Mylan Pharmaceuticals ULC v. Pfizer Canada Inc. / donepezil (NOC) 2012 FCA 103 Mainville JA: Sharlow, Gauthier JJA aff’g 2011 FC 547 Hughes J (ARICEPT, Pat No 1,338,808)

The FCA has affirmed the decision of Hughes J finding that Pfizer’s patent for ARICEPT (donepezil) is not invalid for lack of sound prediction. While the FCA decision does not change the law significantly, there are some interesting hints regarding the false promise doctrine. In particular, the FCA distinguished its own very problematic decision in Pfizer / latanoprost 2011 FCA 236.

A central issue in the case was the interpretation of the promise of the patent, which Hughes J had interpreted as promising a new class of compound, including donepezil, which is effective for the treatment of Alzheimer’s [FC 232]. Mylan, before Hughes J and on appeal, had argued that the patent promised that donepezil would have better toxicity and efficacy than prior art compounds [FCA 49]. The question was crucial because of the interplay with the requirement established in Lilly / raloxifene 2009 FCA 97 [15], that when utility is based on sound prediction, as it was in this case [FC 35], the factual basis for that prediction must be found in the patent itself [FC 226]. A more demanding promise would be less likely to be established by the evidence disclosed in the patent.

Hughes J accepted Pfizer’s interpretation of the promise, and held that a sound prediction of the promised utility had been established. Once Hughes J had determined the promise of the patent, the case turned mostly on the facts, and, as I noted in my post on Hughes J’s decision, and the most interesting aspect of Hughes J’s decision was his approach to the construction of the patent. The question is whether the promise of the patent is a question of fact, in the sense of that the promise is to be determined by expert evidence as to what the posita would understand the promise to be, or rather a question of mixed question of fact and law, in which legal arguments and principles are needed to supplement the expert evidence. As I noted in my earlier post, “Hughes J comes down firmly in the latter camp,” and in this decision the FCA has affirmed that Hughes J reached his conclusion as to the promise of the patent “by applying the correct test.” [FCA 52, approving FC 212-18]. Note that the FCA has reaffirmed that “[t]he promise of a patent is a question of law reviewable on appeal on a standard of correctness,” but the court went on to point out that “generally, the construction of the promise is an exercise that requires the assistance of expert evidence, as the promise should be properly defined, within the context of the patent as a whole, through the eyes of a person skilled in the art or science to which the invention” [FCA 48]. I suggest that given this caveat, it is more accurate to describe it as a mixed question of fact and law, though nothing turns on the label.

Perhaps of more interest, the FCA distinguished its decision in Pfizer / latanoprost 2011 FCA 236 as turning on its “unique circumstance” [56]. At one level this says nothing more than that the promise of a patent turns on its own particular facts; and indeed, perhaps nothing more should be read into this. But it could also be an indication that the FCA intends to pull back from the very aggressive interpretation of the promise of the patent that it indulged in Pfizer / latanoprost.

On an entirely distinct point, Mylan had also argued that Hughes J had erred in not considering certain errors in the specification. The FCA affirmed Hughes J, noting that “[t]he minor bona fide data reporting errors do not materially change the results reported in the patent, nor do they affect the inference which a person skilled in the art or science to which the invention pertains would reasonably draw from these reported results” [46].