Beware, drafters!

This may well be the fourth post almost in a row on a pharma case. Although pharma patent litigation is typically not hyperactive in France, each single case usually generates many interesting questions.

Today is no exception, not only from the litigation perspective but also from the viewpoint of a patent drafter. There are in fact at least two aspects in the decision of the Paris Tribunal de grande instance (TGI) which can be taken as significant warnings for patent attorneys.

The patent in suit is EP 0984957, owned by Swedish company AstraZeneca AB, and it looks quite simple and straightforward.

Claim 1 of the patent simply reads: “the magnesium salt of S-omeprazole trihydrate“.

S-omeprazole, also known as esomeprazole, is a blockbuster drug used in the treatment of gastric ailments. The patent is directed to a specific form of the drug.

Claims 2-4 further specify the form of the drug. Claims 5-8 relate to a process for the preparation of the drug. Claim 9 relates to a pharmaceutical composition comprising the drug of claim 1 and another one. Finally, claim 10 is a Swiss-type claim mentioning the treatment of a gastric acid-related condition.

In July 2011, AstraZeneca initiated infringement proceedings against Ethypharm based on this patent in view of the exploitation by this French company of generic esomeprazole.

Ethypharm of course filed a counterclaim for nullity in due time. But things did not go smoothly, and the lawsuit seemed to drag on forever.

First, an expertise was ordered so as to sort out the documents seized during an infringement seizure. Second, the parties discussed and initially agreed to the designation of another expert, as far as I understand in order to weigh on whether there was an infringement or not. Third, this expert was finally not designated, as AstraZeneca admitted that the generic esomeprazole on the market no longer infringed the patent (while maintaining that there had been infringement in the past). Fourth, AstraZeneca was compelled to file the experimental evidence based on which the above admission was made.

In summary, the judge in charge of case management certainly had her work cut out for her. And this leads us to the judgment issued by the TGI on June 23, 2017.

The first aspect of the decision that deserves a discussion is claim interpretation.

The patent proprietor stated that claim 1 covered any magnesium salt of S-omeprazole trihydrate. But, according to the defendant, claim 1 only protects a specific form of magnesium salt of S-omeprazole trihydrate.

The court went for the latter interpretation.

The court referred to article 69 EPC and the protocol on the interpretation, and remarked that “the judge must not make any interpretation if the claim is self-sufficient and should not denature the claim on the pretext of claim interpretation“.

One may wonder if the court did not do just that, i.e. interpret a claim based on the description, although the claim seemed quite self-sufficient.

At least from an EPO perspective, I have little doubt that a claim simply entitled “the magnesium salt of S-omeprazole trihydrate” would be seen as covering any magnesium salt of S-omeprazole trihydrate based on its plain wording.

But this is not the option that the court used. Instead, the court had a close look at the description of the patent and noted inter alia the following:

Since the wording of claim 1 does not comprise any determiner, one should refer to the description and drawings to interpret it, with respect to the skilled person […]. 

It is also specified that omeprazole and its salts as well as the R and S enantiomers of omeprazole and their salts are known from the art […] and that the magnesium salt of the S enantiomer of omeprazole exists in different forms. 

As mentioned in the description, the field of the invention does not relate to a “novel form of S-omeprazole” as suggested by the title of the patent, since this molecule was already identified, but a “novel form  of trihydrate of the magnesium salt of the S-omeprazole” […], which implies that it is a trihydrate form other than known from the art, with specific features such as “substantially pure” […], devoid of magnesium salts of R-omeprazole […] and devoid of other forms of magnesium salts of S-omeprazole (including the dihydrate form used for the preparation of the composition). 

This product is said to be “highly crystalline” […] since it has a larger crystallinity than any other form of magnesium salt of S-omeprazole, including trihydrate forms […]. 

This compound is characterized by an X-ray powder diffractogram [XRD] which shows main peak positions and intensities […], or by spectroscopy […]. 

Crystalline forms at their best

In support of its proposed interpretation, AstraZeneca filed an affidavit by a doctor Byrn, as well as a judgment by the New Jersey district court on a corresponding U.S. patent, per which the magnesium salt of esomeprazole trihydrate was novel at the time the invention was made and the patent was to be interpreted in a broad manner.

By the court was not convinced and noted that

the prior art previously disclosed a non-pure form a magnesium salt of S-omeprazole trihydrate, as can be derived from the laboratory tests performed on molecules recited in previous patents […]. [And] it can be deduced from the aforementioned elements in the description (notably the very title of the patent and the wording of the claims, the use of determiners in the text of the description such as “A” or “This” […] to mention the product […]) that the invention does not relate to any trihydrate of magnesium salt of S-omeprazole as suggested by AstraZeneca, but to a specific trihydrate having defined features (substantially pure, crystalline, with specific peaks) […]. 

The court repeatedly stated in the judgment that some magnesium salts of esomeprazole trihydrate were known from the art. But it does not seem to me to clearly stem from the patent itself. It is possible that the recreation of prior art esomeprazole could show that this particular salt form was already present, but isn’t this rather an issue of novelty of the claim?

Also, it is extremely striking that the court placed so much emphasis on how the description was drafted.

Here is the thing, I think. Paragraph [0009] of the patent for instance starts with: “the magnesium salt of S-omeprazole trihydrate obtained according to the present invention is substantially free from magnesium salts of R-omeprazole“. Then paragraph [0010] starts with: “the compound of the invention is characterized by the positions and intensities of the major peaks […]“.

If my understanding is correct, it could have made a world of a difference if these paragraphs had mentioned that the compound “according to some embodiments” is substantially free from other salts, or that the compound of the invention “may be” characterized by certain positions and intensities of peaks.

Therefore, beware drafters! Even if you get what you consider a broad claim granted, it may be interpreted by a court in a much narrower manner if the description gives the impression that the invention has a number of other essential features.

Surprising? Well, with Munich eyes, certainly. But not really if you are familiar with French case law.

Today’s decision is for instance very reminiscent of the approach recently taken in the rosuvastatin case. Even electronics cases are handled in a similar manner, as illustrated here.

The TGI’s comment on dependent claims 2-4 is enlightening in this respect. Claim 2 mentions that the compound is highly crystalline. Claim 3 mentions that it is stable. Claim 4 mentions that it has a certain XRD pattern. A common way of looking at this would be to state that claim 1 is broader than claims 2-4 and thus is precisely not limited to the specific XRD pattern, or to a highly crystalline form, etc. But the court reached the exact opposite conclusion and noted that

these claims define the specific features of the compound mentioned in claim 1.

Now, one may criticize the court’s rewriting of straightforward claim 1 and the challenge this presents to legal certainty. 

But there may nevertheless be a possible justification for this bold approach.

As the patent only discloses one very specific crystalline form of trihydrate, it could be argued that the protection should be limited to this specific form and should not extend to other forms of trihydrate which were not actually made available to the public by the patent. Maybe this is what the judges had in mind.

After this section on claim interpretation, the judgment contains a section on sufficiency of disclosure and novelty.

Both grounds of nullity were discarded by the court. In fact, the objection of lack of novelty was put forward only in case the patentee’s broad interpretation prevailed – and this was not the case.

And then comes the other important point in the judgment, namely inventive step.

At this point, the patent was revoked, based on a very brief justification.

The court generally made reference to the problem and solution approach. The dihydrate form of the compound was the closest prior art. According to the patent, the new form is more stable and easier to characterize and synthesize.

But the court refused to take this statement of a technical problem into account:

Yet, beside the disclosure of the molecule on a new form (trihydrate) and the presentation of preparation and identification methods of this product, whereas the pharmaceutical industry wants to find further forms of an active, even if the properties to be expected from the new molecular forms are not known, the patent does not define any problem. It just mentions that the product is more stable, easier to synthesize and handle and identify, without however supporting this statement in the patent itself, by studies and researches and results. Thus, the patent does not mention a problem to be solved let alone demonstrate the resolution of this technical problem. 

Moreover, it is acknowledged that in front of the EPO or in litigation the patentee may refer to posterior tests, but these must consolidate results already contained in the patent […]. 

Therefore, claim 1 is invalid for lack of inventive step as it does not solve a technical problem.

To summarize: the patent does mention a technical problem solved by the invention. But in the absence of any experimental evidence in the patent that this problem is indeed solved, the problem is not taken into account. Post-published evidence is considered to the extent that it can merely supplement data already contained in the patent, but not replace it entirely.

So far so good, and the approach taken by the court seems consistent with EPO case law. See in this respect the catchword of oft-quoted T 1329/04:

The definition of an invention as being a contribution to the art, i.e. as solving a technical problem and not merely putting forward one, requires that it is at least made plausible by the disclosure in the application that its teaching solves indeed the problem it purports to solve. Therefore, even if supplementary post-published evidence may in the proper circumstances also be taken into consideration, it may not serve as the sole basis to establish that the application solves indeed the problem it purports to solve.

However, directly jumping to the conclusion that the claims lack inventive step, as the court did, is something a Board of appeal would probably not do.

Instead, they would likely reformulate the technical problem in a less ambitious manner, e.g. in this case as providing an alternative form of esomeprazole, and would then investigate whether it was obvious for the skilled person to achieve the claimed invention with this unambitious technical problem in mind.

Let’s assume for instance that it was technically difficult to make the trihydrate form. In this case, a Board could arrive at a finding of inventive step. In France, the absence of an ambitious technical problem is in itself indicative of a lack of inventive step.

This confirms that French courts are more severe in the appraisal of inventive step.

At any rate, here comes the second advice for drafters is: beware of the plausibility of the technical effects of the invention!

My understanding is that it is kind of a hot topic at the EPO these days. Well, it is an even more serious matter in this country.

And this does not just apply to “therapeutic” effects.

In this case, the alleged technical effect was not related to the treatment of an illness but rather to physical characteristics of the drug (stability, ease of handling…).

So, we are all doubly warned, I guess.


CASE REFERENCE: Tribunal de grande instance de Paris, 3ème chambre 3ème section, June 23, 2017, AstraZeneca AB v. Ethypharm, RG No. 11/11460.

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