2,379,329 / spinosad / TRIFEXIS
Bédard J’s Lilly / TRIFEXIS decision applies what is now the FCA’s established interpretation of the product specificity requirement in s 4(2) of the NOC Regulations to hold that the 329 patenet cannot be listed on Patent Register against TRIFEXIS, notwithstanding that a generic version of TRIFEXIS would necessarily infringe. As Bédard J pointed out, she was bound to come to this conclusion by the FCA decisions in Purdue / TARGIN 2011 FCA 132 (blogged here) and Gilead / COMPLERA 2012 FCA 254 (blogged here), which held that all the active ingredients in the product must be specifically mentioned by name in the claims. While there is no new law here, the decision illustrates the extreme nature of the product specificity requirement. Bédard J held expressly that a generic version of TRIFEXIS would infringe, and the description specifically mentioned the ingredient that was missing from the claims; but as Bédard J pointed out, neither of these points is a principled basis for distinguishing the prior FCA decisions. This further emphasizes that in order to ensure that a patent will be listable against the commercial product, it is not enough that the commercial product would clearly infringe, or even that the patent specifically describes all the ingredients of that product. The claims must specifically name the all of exact compounds found in the NOC. Bédard J aptly referred to this as a requirement of a “perfect match” . References to a class of compounds, that would enable fewer, shorter, and clearer claims, do not suffice to allow listing, no matter whether they are fully adequate for infringement; all the members of the class must be listed in the claims themselves in order to ensure that a patent can be listed against the ultimate commercial product. This is a purely formal requirement, since all of the specific compounds could in principle be named in the claim itself, without changing the meaning of the claim, though it would make the claims bloated and difficult to interpret. This product specificity requirement also has the perverse effect of making it relatively easy to list an “evergreening” patent, in which a very specific change is made to an existing formulation, while making it almost impossible to list a true breakthrough patent, where the precise formulation of the ultimate commercial product is unknown at the time of filing.
TRIFEXIS is authorized as an oral dosage form of a drug that contains two active medicinal ingredients: spinosad and milbemycin oxime. The 329 patent claims an oral “formulation” of spinosad. The patent description defines “oral formulation” as follows (Bédard J’s emphasis, ):
The formulations of this invention may further include, in combination with the spinosyn component, one or more other compounds that have activity against the specific ectoparasite or endoparasite to be controlled, such as, for example, synthetic pyrethroids, natural pyrethins, organophosphates, organochlorines, carbamates, foramidines, […].milbemycins, […]
The term “oral formulation” means that the spinosyn component or components, either alone or in combination with one or more of the other types of compounds listed supra, formulated into a product or formulation suitable for administering to the animal by mouth.
Consequently, Bédard J construed the relevant claims of the 329 patent to be directed “not only to a formulation including spinosad as the only active ingredient, but also to formulations that include other active ingredients such as, but not restricted to, milbemycin oxime” . Thus she in effect held that a generic version of TRIFEXIS would necessarily infringe the 329 patent.
However, this was not enough. While it is permitted for a patentee to create their own dictionary in the specification for the purposes of claim construction in the context of infringement, this is not permitted for the purposes of the product specificity requirement. The product specificity requirement of s 4(2)(b), requires “a claim for the formulation that contains the medicinal ingredient.” Notwithstanding that the claim of the 329 patent literal “contains” a claim to spinosad, “the medicinal ingredient” has been construed by the FCA as meaning all of the specific ingredients. It is “insufficient for a patent to meet the product specificity requirement by referring to a class of compound rather than to a specific medicinal ingredient” . Rather, as Bédard J put it, there must be “a perfect match” between what is claimed and what has been authorized . Note that the Minister’s position is that the exact text appearing in the NOC must appear in the claim. There are various types of milbemycins, and the Minister’s position was that it would not have been enough to refer to “milbemycin” in the claim; it would be necessary to refer to “milbemycin oxime” . It is not entirely clear whether Bédard J accepted this position. She held that “Referring to the general family of milbemycins in the definition of oral formulation is not specific enough to conclude that the claims match the formulation contained in Trifexis” . It is not entirely clear to me whether what was inadequate was the reference to the general family, or the fact that the reference was only in the specification, or both. That is, would the product specificity requirement have been satisfied if the claims, and not just the disclosure, had referred to milbemycins, but without reference to milbemycin oxime in particular? It is, however, clear that the Minister’s position is that a reference to milbemycin oxime in the claim itself is necessary, and this does seem to follow from the stringent nature of the product specificity requirement.
It must be emphasized that the specificity requirement is purely formal. By defining “oral formulation” in the disclosure, the claims were made more compact, but without changing the meaning of the claim at all, the definition might have been included in the claim by specifically listing synthetic pyrethroids, natural pyrethins, organophosphates, organochlorines, carbamates, foramidines, avermectins, milbemycins, insect growth regulators, nitromethylenes, pyridines and pyrazoles as compounds which would also be included in the formulation. Of course, according to the Minister this would not suffice. It would be necessary to specifically list the various types of milbemycin, namely (according to Wikipedia) milbemectin, milbemycin oxime, moxidectin, and nemadectin; and all the specific types of all the other possible components, such as organophosphates, would have to be similarly extensively listed in the claim itself. None of this would change the substantive meaning of the claim; it would be purely a formal change – and a formal change very much for the worse, as it would bloat the claim, making it much harder to understand.
I must say that I really cannot understand what purpose is served by this purely formal requirement. It is a dramatic departure from the general principle of purposive construction that is otherwise universally used in Anglo-Canadian law for the interpretation of patents and contracts, not to mention statutes. It has a perverse effect of making it relatively easy to list an “evergreening” patent, in which a very specific change is made to an existing formulation, while making it almost impossible to list a true breakthrough patent, where because the precise formulation of the ultimate commercial product will rarely be known at the time of the pioneer patent. Perhaps the answer is that no purpose is served, as the holding of the FCA in Gilead / COMPLERA 2012 FCA 254 (blogged here), was based on a textual analysis. In any event, Bédard J did not address any of these problems of principle, for the very good reason that these problems are inherent in the holdings of the FCA in Purdue / TARGIN and Gilead / COMPLERA, and she is bound by those decisions .