Friday, September 25, 2020

Time to Relegate IG Farbenindustrie to the Dustbin of History

 Eli Lilly Canada Inc v Mylan Pharmaceuticals ULC 2020 FC 816 St-Louis J

            2,371,684 / tadalafil / CIALIS ADCIRCA

Yesterday’s post discussed the issues raised by the anticipation analysis of this decision. This post discusses the issues related to selection patents.

To repeat the background from yesterday’s post, Lilly markets 2.5mg, 5mg, 10mg and 20mg strengths of tadalafil for the treatment of erectile dysfunction [11]. The defendants in this action are various generics that want to sell tadalfil in those dosage forms [13] The asserted claims of the 684 patent are to dosage forms of tadalafil for treating ED, namely doses from 1 to about 20 mg, as well as specific doses within that range, including 2.5, 5, 10 and 20 mg doses: [197-213].

The question in this case was whether the 684 patent is valid over the prior art 2,226,784 application, which claims tadalafil for the treatment of ED, and discloses unit doses of tadalafil from 0.2 to 400 mg. St-Louis J held on the facts, that starting from the knowledge that doses from .02 to 400 mg were useful, it would be routine for the skilled team to carry out the trials necessary to narrow that down to the range providing the best balance between efficacy, and safety and tolerability, and they would be motivated to do so [325-28]. The claimed invention was therefore obvious to try [323, 330].

While that much was straightforward, the decision has a long discussion of whether the 684 patent is a selection patent, ultimately concluding that it is not [116–136]. Everyone, including St-Louis J and both parties, seems to have been of the view that this was central to the assessment of validity: “the determination that a patent is not a selection patent has consequences, as the purported advantages relied upon by the patentee, if not in the claims, may not be considered in the assessment of novelty and inventiveness, as examined later on” [128]; the defendants argued that “the 684 Patent is necessarily anticipated and invalid unless it is a selection patent” [226], on the basis that “a dosage range out of a broader disclosure is anticipation, unless the patent qualifies as a selection” [229]. See also [136], [235], [238], [263], [306], [310], and throughout, distinguishing cases depending on whether or not they related to a selection patent (see eg [286–88]).

In my view, this wrong. In Lilly / olanzapine 2010 FCA 197, [4], [27], [33], the FCA emphatically affirmed that the conditions for a valid selection patent set out in IG Farbenindustrie (1930), 47 RPC 289 (Ch), and approved by the SCC in Sanofi at [9]-[11], do not constitute an independent basis upon which to attack the validity of a patent. The argument in this case seems to be that these conditions can nonetheless be an independent basis upon which to uphold the validity of a patent, though not to attack it, because the putative advantages can be considered if it is a selection patent, but not otherwise. This must be wrong.

In the first place, as the FCA pointed out in Lilly / olanzapine “the Act contains no reference to invalid selection” [29]. This point cuts the other way: validity is determined on the basis of the statutory conditions, not otherwise. It doesn’t matter whether selection patents are uniquely susceptible to attack, or uniquely immune from attack, because neither option has any basis in the Act.

Further, the distinction between attacking and upholding a patent on the basis of it being a selection is not tenable. St-Louis J relied on the IG Farbenindustrie conditions as setting out the requirements that must be met before an unexpected advantage can be considered [129]. She held that because those conditions were not satisfied, the unexpected properties could not be considered [136]. So, failing to satisfy the IG Farbenindustrie conditions is not in itself a ground for invalidity, but failing to possess these qualities may result in a patent being held invalid because the unexpected properties that might be invoked to save the patent if the conditions were satisfied, cannot be considered. To my mind, this is simply a roundabout way of invalidating the patent for failure to satisfy the IG Farbenindustrie requirements. Consequently, this analysis is contrary to the FCA holding in Lilly / olanzapine 2010 FCA 197. (I expect that St-Louis J’s analysis was influenced by the decision of de Montigny J in the NOC proceedings involving the same patent, 2015 FC 125, which has some of the same problems (see eg [147–48], even though he started off by emphasizing, correctly in my view, that “the jurisprudence has established that a selection patent is like all other patents and is governed by the same legal principles” [108].)

St-Louis J’s determination on the facts of whether the 684 patent was a selection patent also demonstrates problems with the whole approach. Her discussion is quite brief. “I note first that the 684 Patent, filed in 2000, makes no mention of the 784 Application, published in 1997" [131]. The difficulty with this observation is that it is not set out in IG Farbenindustrie, or anywhere else that I know of; it is certainly not based on the Act.

Next, and “[m]ore importantly”:

[132] in regards to Lilly’s argument that the substantial advantage of the 684 Patent lies in the better than sildenafil flushing side effect at 2 to 20mg, I conclude that there is nothing in the specification, or the claims themselves, to the effect that the advantage is peculiar to this particular dosage to the exclusion of any other unit dose, nor does it assert that a larger number of unselected doses do not possess the same advantage, which is an essential characteristic of a selection patent.

This evidently addresses the third IG Farbenindustrie requirements, which is that “The selection must be in respect of a quality of a special character peculiar to the selected group. . . . if research showed that a larger number of unselected compounds possessed the same advantage, the quality of the compound claimed in the selection patent would not be of a special character.”

An initial difficulty is that St-Louis J’s statement could be construed as saying that the fact that the patent does not state that the advantage was peculiar to the particular dose is in itself fatal, whether or not the advantage is in fact peculiar to the dose. If so, it is a novel requirement.

It is more likely that St-Louis J is simply saying that that the evidence did not establish that the third condition is satisfied. This suggestion is taken up at [133]. The difficulty here is that the third condition has no clear statutory basis. The FCA in Lilly / olanzapine stated at [32] that “the notion of selection permeates the entire analysis in relation to each of the grounds of alleged invalidity”: which statutory basis for invalidity is permeated by St-Louis J’s holding in [132]? Applying the third requirement without a statutory basis is particularly problematic, given that the EWCA in Dr Reddy’s [2009] EWCA Civ 1362 [39] has rejected it as being unsound in principle.

In Sanofi at [11] the SCC remarked that “Maugham J.'s analysis [in  IG Farbenindustrie] is consistently referred to and is well accepted.” This was no longer true: just a year after Sanofi was decided, the EWCA in Dr Reddy’s rejected reliance on the IG Farbenindustrie requirements, in part because they had no statutory basis [36]-[38], and in part because of substantive criticisms [39]. Jacob LJ stated that “the best thing to do is to regard them as part of legal history, not as part of the living law” [37]. In my view, we should do the same in Canada. The SCC in Sanofi did not require the use of the IG Farbenindustrie factors, but only said “it is a useful starting point for the analysis to be conducted in this case” [11]. In practice, the IG Farbenindustrie requirements have turned out not to be helpful at all; on the contrary, they have added confusion and complexity to the law, with a concomitant likelihood of error. Moreover, while the SCC endorsed the IG Farbenindustrie requirements, it did not actually apply them in its analysis on the facts; the SCC relied on IG Farbenindustrie only for the proposition that “A system of genus and selection patents is acceptable in principle” [19]. Otherwise the SCC relied entirely on universally applicable principles of anticipation and obviousness. I suggest that the the Federal Courts should take the same approach: a system of genus and selection patents is acceptable in principle, but whether any particular patent is valid depends on the standard principles of anticipation and obviousness, and not on whether the patent at issue can be characterized as a selection patent.

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