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Prohibition application against gliclazide modified release tablets dismissed

On February 16, 2015, Mr. Justice Roy released his public Judgment and Reasons in a prohibition application involving Servier, Apotex and a generic version of 60 mg gliclazide modified release tablets.

The patent at issue, Canadian Patent No 2, 629,670, is directed to a breakable or divisible modified release tablet of gliclazide, a hypoglycemic agent that helps maintain sugar levels in the blood of diabetic patients.  According to the 670 Patent, portions of the divisible tablet will have a similar or identical dissolution profile as the whole tablet. The claimed formulation has three components: gliclazide, a cellulose derivative and a binder.

Non-infringement  – dissolution profile

One issue between the parties was whether the dissolution profile was to be measured in vitro or in vivo.  In accepting Apotex in vitro construction, Justice Roy relied on the following passage from the disclosure:

In the context of the invention, the expression “identical dissolution profile” is intended to mean dissolution kinetics having variation coefficients with no statistical difference between them. The identical in vitro dissolution kinetics according to the invention give identical plasma kinetics.

In rejecting Servier’s in vivo construction, Justice Roy held that it would improperly require “in vivo” to be read into the into the first sentence of the passage above. Servier never justified how there would be two types of dissolution kinetics in the same definition.

Non-infringement – binder

The purpose of the binder in the 670 Patent was to agglutinate particles that cannot be agglutinated under pressure alone. Servier’s theory of infringement argued that the same excipient could be both the cellulose derivative and the binder. Justice Roy rejected this construction, holding that the patent forcefully suggests that the binder and the cellulose derivative will be different excipients. Based on this construction, Servier had failed to discharge its burden of demonstrating Apotex’s allegation of non-infringement was not justified.

Obviousness

Prior to the claim date it was known that modified release formulations could be scored to allowing breaking while maintaining a desired release rate.  The prior art also discussed methods of overcoming the problems associated with divisibility in modified release tablets.  Justice Roy held that it was plain and more or less self-evident that if the matrix was adjusted and the proper scoring was selected, the resulting gliclazide tablet would have the desired dissolution profile. Specifically, there was no evidence to suggest that gliclazide was not a suitable candidate to be incorporated into a divisible tablet:

 [189] Given the routine nature of the experimentation required to reach the claimed invention, the skilled person, wanting to combine the prior art regarding tablet divisibility and dissolution profiles with a gliclazide formulation, would have pursued that experimentation and made the necessary adjustments – either to the matrix formulation, the scoring of the tablet, or both – to reach it.

Once Apotex had put the issue in play, it fell to Servier to satisfy the Court that it was not obvious to try the claimed invention. Justice Roy did not accept Servier’s evidence on the inventors actual course of conduct.  At the relevant time, Servier was pursuing many goals.  Time spent to obtain goals other than the invention presented in the 670 Patent was not relevant to whether the claimed invention was obvious to try.

No demonstrated utility

Justice Roy, following the Court of Appeal in Apotex Latanoprost, held that where a patent claims utility on the basis of a result obtained prior to the Canadian filing date, the disclosure must make reference to a study demonstrating that the patent does what it promises to do. Since the bioequivalence studies performed by Servier prior to Canadian filing date are not referred to or alluded to in the 670 Patent, they were not relevant for establishing demonstrated utility. Further, while the 670 Patent did disclose results of an in vitro dissolution test on a single formulation, none of the asserted claims were limited to that specific formulation and  Justice Roy concluded that this was not sufficient to demonstrate or soundly predict utility across the entire spectrum of the claimed invention.

No soundly predicted utility

Where a prediction is made sound by testing, those tests must be disclosed in the patent.  Justice Roy concluded that the dissolution results of a single formulation reported in the 670 Patent did not provide an adequate factual basis for sound prediction across the claimed monopoly or with respect to in vivo dissolution profiles.  Justice Roy held that there was not sound and articulated line of reasoning bridgeingteh gap between the factual basis and the predicted utility. Justice Roy indicated that he was left with the impression that the 670 Patent “played a game of hide-and-seek”.  Without proper disclosure, it cannot be said that the public is receiving their proper share in return for the patent and monopoly.

A copy of Justice Roy’s Judgment and Reasons may be found here.