Today, it is back again to one of the topics regularly addressed on this blog, namely the statute of limitations for patent nullity actions in France (but not only!).
Matthieu Dhenne was kind enough to send me a brand new decision from the Paris Tribunal de grande instance (TGI) which, once more, sheds new light on this thorny issue.
The patent at stake is the French part of EP 1455756, to Merck Sharp & Dohme Corp. (MSD). The patent was granted on July 9, 2008. It was opposed by two generic drug manufacturers. At first instance, the patent was maintained in amended form, according to a decision dated December 3, 2010. The opponents appealed, and their appeals were dismissed by the Board of appeal in a decision dated July 17, 2014. The publication of the amended patent took place on September 23, 2015.
Soon thereafter, on December 2, 2015, Ethypharm filed a nullity action with the Paris TGI, requesting that the French part of the patent should be revoked.
Quite predictably, MSD argued that the nullity action was time-barred.
If one directly applied the recent case law of the Paris Cour d’appel (discussed here), this should be a winning argument. Indeed, the Cour d’appel has proposed that the five year-limitation period be computed from the date of grant of the patent. With this in mind, in this case, the limitation period would have ended on July 9, 2013.
But you and I know that things are not that straightforward, as the Paris TGI does not follow the case law of the upper court, and generally favors an in concreto determination of the starting point for the limitation period (see a recent example here).
Yet, in today’s ruling you will not find any protracted discussion of an in concreto starting point. Instead, the issue is disposed of in just one paragraph:
[…] It is only on [July, 7, 2014, i.e. the date of the Board of appeal’s decision] that the drafting of the patent which is sought to be revoked was stabilized and that Ethypharm was able to precisely know the content of the claims of said patent as well as all the facts making it possible for them to act, so that the action is not time-barred and is admissible.
I must say I have mixed feelings about this.
My initial reaction was, oh no, you must be kidding me, there is now yet another way of determining the starting point for the limitation period? This is not legal uncertainty anymore, this is legal chaos.
A few seconds later, I thought, well yes, it does make sense after all, you can’t possibly be expected to shoot at a moving target. When a patent is modified during opposition proceedings, any appeal filed at the EPO has a suspensive effect, and thus it is only once the appeal proceedings are terminated that the content of the patent is final.
A party must act within five years from the date at which they knew or should have known that the patent at stake is a possible impediment for their current or future business activities, or else be time-barred (this is more or less what I understand to be the TGI’s usual position). And how can a party know this before the patent is even its final form?
However, this ruling raises more questions than it provides answers.
What if an opposition is rejected by the opposition division and the patent thus maintained as granted instead of as amended? Should the reasoning be the same? What if an opposition is filed by a straw man (which is allowable at the EPO) and there is thus an unverifiable suspicion that the nullity claimant itself may be the true opponent, in an attempt to artificially extend the limitation period by several years?
In his message to me, Matthieu Dhenne also noted that the court’s reasoning could be applicable to other situations: limitation proceedings, but also a prior nullity suit brought forward by a third party. Taking this one step further, he observed that a patent right can in fact be modified at any time and is therefore theoretically never “stabilized” until it expires (sometimes, it can even be retroactively “stabilized” only after its expiry). He thus suggested that the full consequence of the court’s reasoning should be that the limitation period can only start running at the expiry of the patent, so that the well-identified drawbacks of this limitation period should in practice never occur.
Matthieu added that there would thus be a complete parallelism between the limitation period for infringement actions and nullity actions. Accordingly, invalid patents would not be able to unduly hinder free competition.
Definitely an interesting suggestion, but is it really what the TGI had in mind? I am quite sure we can expect more surprises in future decisions.
Apart from this, the decision is worth the read beyond the admissibility part.
First, it turns out that the nullity claim was held ill-founded on the merits and thus dismissed. As the patent in suit is a pharma patent, this is already quite remarkable. A majority of pharma patents which are litigated in this country are revoked one way or another.
Second, the decision tackles the very interesting issue of plausibility.
In the present case, Ethypharm argued that the patent was of the speculative kind, which resulted in insufficiency of disclosure and lack of inventive step.
Now may be a good time to have a look at claim 1:
A nanoparticulate composition comprising the compound 2-(R)-(1-(R)-(3,5-bis(trifluoromethyl)phenyl)ethoxy)-3-(S)-(4-fluoro)phenyl-4-(3-(5-oxo-1H,4H-1,2,4-triazolo)methylmorpholine, or a pharmaceutically acceptable salt thereof, the compound having adsorbed on the surface thereof at least one surface stabilizer in an amount sufficient to maintain an effective average particle size of less than about 1000 nm; where “effective average particle size of less than about 1000 nm” means that at least 95% of the particles, by weight, have a particle size of less than about 1000 nm.
This drug composition is useful in the treatment of nausea and vomiting, especially those induced by a chemotherapeutic treatment. The short name of the active compound is aprepitant. According to the patent, the technical problem at stake was to improve the bioavailability of aprepitant. This is stated in the patent but no experimental test results are present, which led Ethypharm to consider that there was no evidence in the patent that the technical problem was properly solved.
Ethypharm also tried to use some of MSD’s posterior testing against them, by claiming that they proved that there were features missing in the patent which were essential for successfully implementing the invention.
The court was not convinced that there were indeed such essential features missing. The court also noted that there was a reference in the patent in suit to a prior U.S. patent disclosing the so-called “Nanocrystal” method, for making nanoparticles with a surface modifier adsorbed thereon, having an average size of less than 400 nm. This Nanocrystal patent also taught that such nanoparticles improve the bioavailability of poorly water-soluble actives.
Thus, said the court, the improvement in bioavailability provided by the nanoparticle form of aprepitant was plausible.
In such a case, the court continued, evidence which is external to the patent can indeed be taken into consideration for demonstrating that the technical problem is solved. The court then reviewed a number of articles and reports and was satisfied that the technical effect of improving bioavailability was well achieved.
In summary, this is an important decision for the fine-tuning of the appraisal of a speculative patent-type objection.
To me, the take-away message is that a reference in a patent to a prior art document disclosing a technical effect provides some plausibility that the technical effect is indeed achieved.
The patent survived other attacks of insufficiency of disclosure, extension of subject-matter and lack of inventive step. Quite remarkably, the main claim was in particular found to be non-obvious over the “Nanocrystal ” European patent of the same family as the U.S. patent mentioned above, which was used for supporting the plausibility of the technical effect.
The court held that:
[The “Nanocrystal” prior art] does not disclose chemical structures or features of drugs intended to be used by this process. It only mentions that it can be implemented with a large variety of medicinal substances, the substance having to be poorly soluble, that is less than 10 mg/mL, so that the skilled person does not know which actives […] can be tested with a reasonable expectation of success. He was all the less incited to do so that in December 2001, i.e. almost ten years after the priority date of [the Nanocrystal patent], the nanonization process, which has a number of constraints (in particular the heat released during milling may change the structure of the active substance and reduction to a very small size may create a problem of chemical and physical stability), was used on only four active substances (danazol, steroid A, compound WIN 63,394 and naproxene) with a verified effect on bioavailability […].
I have the uneasy feeling that there may be a contradiction here between the sufficiency and inventive step prongs of the court’s reasoning.
If the teaching of the Nanocrystal patent cannot be applied in an obvious manner to aprepitant, and if there are many technical uncertainties, why is it then not necessary for the MSD patent to contain evidence in the form of experimental tests showing that the process can in fact be effectively applied to this particular drug?
CASE REFERENCE: Tribunal de grande instance de Paris, 3ème chambre 2ème section, January 26, 2018, Ethypharm SAS v. Merck Sharp & Dohme Corp., RG No. 16/01225.