Sleeping Easy Again - Cephalon v Orchid [2011] EWHC 1591

Emerging, blinking, from the dark confines of the pile of examination scripts that he has called his home for the past few weeks (which in the best cases have been a joy to behold and in the worst a veritable papier-mâché bunker of Babel), this Kat has spent a rather pleasant afternoon easing himself back into the real world again by digesting the latest judgment from Mr Justice Floyd: Cephalon v Orchid & Mylan [2011] EWHC 1591 (Pat).

Cephalon and its subsidiaries owned the rights in three patents: EP(UK) Nos. 0 731 698 (“698”), 0 966 962 (“962”) and 1 088 549 (“549”), all of which contained very similar disclosure and shared a priority date of 6 October 1994. The patents related to the drug modafinil, used to treat sleep disorders such as narcolepsy. Orchid were the manufacturer of generic modafinil which the second defendant (“Mylan”) intended to market in the UK. Cephalon opposed this marketing and so brought an action for infringement. The matter came before Mr Justice Floyd, who handed down his judgment today.

By way of background, modafinil was discovered by Lafon in France in 1976. During the course of clinical trials conducted in the United States some years later, Cephalon noticed that the formulation used by them displayed increased side effects as compared with equivalent doses tested in European clinical trials. They eventually concluded that this was down to the size of the particles making up the input active pharmaceutical ingredient (the “API”) used in the US trials. Essentially, the ease of modafinil’s dissolution within the body was increased by reducing this particle size. Accordingly, a smaller dose of the drug could be used to achieve the same results (and generate the same side effects).

Cephalon therefore applied for the three patents that form the basis of this action: '698 claimed the pharmaceutical compositions themselves; '962, drafted in the so-called “Swiss” form, related to the use of the substance “in altering the somnolent state of a mammal”, which is how this Kat would encourage everyone to refer to things that affect their sleep patterns from now on; and '549 referred to a manufacturing process for the medicament.

Following identification of the skilled addressee and discussion of their common general knowledge, the Judge turned to the issue of construction.

As Floyd J explained:

[36] “The principal issue which divided the parties on the issue of construction is whether the claims were referring to the particle size within the composition (Cephalon’s contention) or whether they were referring to the particle size in the active ingredient used to make the composition (Mylan’s contention).”

Taking the patents one by one, Floyd J noted that the skilled person would approach the ‘698 patent “with the teaching of the patent and the background knowledge … firmly in mind.” Accordingly:

[41] “…[H]e would have seen that the patentee had described his experiments by reference to measurements on the bulk API and that, throughout the specification, the patentee uses measurement on bulk API to explain the observation of different clinical effects observed in clinical trials on tablets of modafinil. This background and context would give rise to a very strong presumption that the patentee was using the language of the claim to mean the particle size of the input API, even though this was not what he had expressly said.”

He continued, noting that:

[44] “The background common general knowledge also points strongly in favour of the conclusion that the patentee must have meant particle size to be measured on the bulk API. Particle size is never measured in the dosage form, and the skilled person would not know how to do so. The skilled person would be pre-disposed to understanding the language of the claims to mean particle size as measured in the bulk API.”

However, he also explained that this conclusion was to be placed against the “considerations of language and purpose” that had been urged by counsel for Cephalon:

[46] “…So far as the language of the claim is concerned, it is true that construed literally, and acontextually, it means the particle size within the dosage form. In relation to purpose, if alerted to the case where the particle size in the dosage form is significantly different from the input API, it is also true that the skilled person would say that the particle size in the composition was what mattered, as that is what the patient will swallow.”

Mr Justice Floyd was not, however, of the opinion that the skilled person would find themselves drawn to this literal construction:

[46] “…The patent is intended to be a practical document addressed to technical people in industry. I have no doubt that to such an addressee the term “composition comprising … modafinil particles, wherein at least about 95%” would be understood as referring to the input API. The matters on which Mylan rely would lead him to reject the alternative meanings as impractical. He would see nothing illogical, or contrary to the purpose of the invention, in the use of the API measurement as a measure of how to achieve the beneficial effects of the patent. So purpose and meaning are aligned: only literalism stands in the way.”

The same was true for ‘962: it was the size of the particle in the API that was important.

Finally, the Judge addressed claim 1 of the '549 patent (at [49]). This was, he said, “not a happy example of claim drafting, particularly given the simplicity of the subject matter”, but nevertheless concluded that “the skilled person would understand that … it is the bulk API which he had to measure, and not that in the formulation.”

The death knell for the infringement action was therefore rung, it being common ground that if Mylan’s construction was the correct one then it was operating outside of the scope of the claims.

All was not at an end however, as Mylan, following the lead of irked alleged infringers everywhere, had counterclaimed for invalidity of the patents that had threatened it. They based their attack primarily on obviousness, but also sought to deploy an insufficiency argument as a squeeze on construction should the need have arisen.

Mylan’s assault on the inventive step of Cephalon’s patents essentially revolved around the question of whether it was obvious to use modafinil particles with reduced particle size (i.e. 95% cumulative particle size <200 μm/median particle size <50-60 μm) to make a modafinil formulation. The Judge considered that in light of the common general knowledge and an entry in a publication called “Drugs of the Future” (identifying modafinil, a method for its manufacture, its dosage range and containing summaries of some clinical trials in human volunteers), it was. He explained that:

[82] “…[Even taking] into account the environment or “milieu” in which the notional formulation project is supposed to be taking place (see e.g. Dyson v Hoover [2001] EWCA Civ 1440; [2002] RPC 22 at [88])…, the evidence did not establish that there was any established mindset that anything which met the target dissolution rate would be good enough. In fact the position was to the contrary…. I have no difficulty in accepting that ethical pharmaceutical companies would be motivated to achieve the best formulation which the application of common general knowledge could provide. Indeed the technical mindset was, in stark contrast to that in Dyson, that improvements in bioavailability could be made by reducing particle size, and that the target dissolution rates did not represent any sort of limit.”

Accordingly, the patents were declared to be invalid.

For the sake of completeness, the Judge also addressed the arguments made in relation to sufficiency, noting that whereas the ‘698 patent survived the attack, the process patent, ‘549, was not so fortunate:

[92] “…On Cephalon’s construction, these claims cover a class of processes in which the particles in the API are outside the claim but the particles in the composition are within it. On this basis the specification of the patent is clearly insufficient. The skilled person would have no way of telling, in the case of this class of processes, whether he was using the invention or not.”

The use claims of ‘962, the Judge noted, would have also failed for the same reason had he not already declared the patent to be obvious.