Product specificity requires “perfect matching”

In Eli Lilly Canada Inc. v. Canada (Attorney General) , Justice Bédard of the Federal Court ruled that the Minister of Health’s  decision to refuse to list Canadian Patent No. 2,737,329, on the patent register against Eli Lilly’s  veterinary  product TRIFEXIS, was reasonable, despite the fact the Minister erred in the construction of the patent. In so finding, the Court dismissed Eli Lilly’s application for judicial review of the decision of the Minister that denied listing the ‘329 patent because it did not meet the product specificity requirement set out in under paragraph 4(2)(b) of the Patented Medicines (Notice of Compliance) Regulations . The decision highlights the stringent nature of the product specificity requirement.

TRIFEXIS, an oral dosage veterinary drug, contains two medicinal ingredients: spinosyn and milbemycin oxide. Eli Lilly sought to list the ‘329 Patent on the register on the basis that the patent claimed a formulation containing both the medicinal ingredients listed in TRIFEXIS.

329 Patent

The relevant portion of the 329 Patent’s independent claims are as follows:

A single-dose oral formulation for controlling an ectoparasite infestation on a dog or cat comprising an ectoparasiticidal amount of spinosad, or a physiologically acceptable N-demethyl derivative or salt thereof, and a physiologically acceptable carrier in a dosage form…

Each of the independent claims specifically references the ingredient spinosad. The independent claims also reference the term “oral formulation” that is defined in the disclosure portion of the patent as:

 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, […] [emphasis added]

Minister’s Decision

The Minister initially refused to list the patent on the basis that the ‘329 Patent did not contain a claim specifically referencing both spinosad and milbemycin oxide as required under the Regulations; and in the alternative, that the disclosure did not explicitly mention milbemycin oxide but only referenced the family of compounds it belonged to, Milbemycins.

In so finding, the Minister rejected Eli Lilly’s submission that not only did each claim specifically reference spinosad, but each claim also referenced milbemycin oxide indirectly as each claim referenced “oral formulations”, a term defined in the patent disclosure. Therefore, rejecting Eli Lilly’s assertion that an in-direct reference is sufficient to meet the product specificity requirement.

Court’s Findings

Applying a standard of correctness, the Court held that the Minister erred in interpreting the patent in a manner that was too restrictive. The Court found that even though the Minister’s decision was focused too much on the requirements under the Regulations, the Minister’s reasoning made it clear that she understood the patent as not claiming a formulation containing both spinosyn and milbemycin oxide. Such an interpretation was found to be too narrow a construction of the 329 Patent.

Justice Bédard construed the claims in 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, milbemycine oxime.  Despite this finding, Justice Bédard ruled that the finding that the Minister erred was not conclusive of the eligibility of a patent to be listed under the Regulations.

Matching is Essential to Meet the Product Specificity Requirements

Justice Bédard ruled that the referring to the general family of milbemycins in the definition was not specific enough to conclude that the ‘329 Patent claims match the formulation contained in Trifexis. In arriving at this decision, the Court felt bound by the jurisprudence including most recently the Federal Court of Appeal’s ruling in Gilead Sciences Canada Inc. v Canada (Ministry of Health). In Gilead, the Court of Appeal endorsed Justice Mosley’s reasoning pertaining to the product specificity requirement, including the finding that it was insufficient for a patent to meet the product specificity requirement by referring to a class of compound rather than to a specific medicinal ingredient.

Justice Bédard, commenting that product specificity requires “perfect matching”, noted at para. 73 that:

“The jurisprudence has been consistent that the current version of subsection 4(2) of the Regulations, as amended in 2006, has introduced a product specificity requirement and that there must be a perfect match between what is claimed and what has been authorized. In the case of a claim for a formulation, all of the medicinal ingredients included in the drug product as authorized must be included in the patent claims.”

The Court rejected Eli Lilly’s argument that Gilead enhanced the product specificity requirement. Interestingly, the Court did not address, in its findings of ineligibility, Eli Lilly’s argument that the FCA in Gilead had not considered the product specificity requirements under the Regulations in light of Canada’s obligations under TRIPS and NAFTA.

In the end, even though the Court’s ruling in Eli Lilly does not add anything new to the law or principles of product specificity under the Regulations, it does further entrench the requirement that the there must be exact matching between the patent claims and the approved product before a patent is listed on the patent register.

A copy of the Justice Bédard’s reasons may be found here.