Eli Lilly v Fresenius Kabi: a decision far from equivalent to what has been decided before

Little did the PatKat know, but she was
about to get a message from the Dutch
court saying that all may not be well in the
land of equivalence

The pemetrexed saga has, by now, obtained a hit-series-like status, with new decisions coming regularly and even more decisions yet to come.  IPKat friend, Alexander de Leeuw (Brinkhof) reports on the latest installment in the Netherlands.

Over to Alex:

"On 19 June 2019 the Dutch District Court of The Hague – the Court with exclusive jurisdiction over patent matters in the Netherlands – issued a decision in merits proceedings between Eli Lilly & Company and Fresenius Kabi regarding Fresenius’ pemetrexed product (a machine translation as published by Mattie de Koning of Simmons is found here). 

The product ‘Pemetrexed Fresenius Kabi’ is practically identical to Lilly’s pemetrexed product Alimta, apart from the fact that it contains the tromethamine salt instead of the disodium salt of pemetrexed. The question in many of the pemetrexed proceedings has been whether a pemetrexed product with a different salt falls within the scope of Lilly’s patent, which specifically claims disodium as the salt to be used in a combination therapy with vitamin B12 or a derivative thereof.

Other than in almost all preceding decisions, the Dutch Court ruled that there is no infringement of Lilly’s patent because tromethamine cannot be considered equivalent to disodium. A copy of the Dutch decision can be found here.

Recap

There have been many proceedings regarding Lilly’s patent for pemetrexed (EP 1 313 508 B1). In short, the patent claims the use of “pemetrexed disodium” in combination with vitamin B12 (claim 1) and a folic binding protein binding agent (claim 2). Generic companies developed pemetrexed products in which a different pemetrexed salt is used, such as dipotassium, diacid, and tromethamine, assuming that this would not be covered by the claims of the patent. What followed was an extensive international debate about scope of protection and the doctrine of equivalence.

A short recap (covering only the tip of the iceberg): In the UK these proceedings went all the way up to the Supreme Court, ruling that Lilly’s patent also covers other salts than pemetrexed disodium. In Germany the case went up to the Bundesgerichtshof (German Supreme Court), which ruled that the lower courts applied the doctrine of equivalence incorrectly by limiting Lilly’s patent to pemetrexed disodium. Similarly, in Switzerland the Bundesgericht (Swiss Supreme Court) ruled that other salts are covered by Lilly’s patent. In the Netherlands, both the District Court of the Hague and Court of Appeal of the Hague ruled in PI proceedings that Lilly’s patent covers other salts than pemetrexed disodium. Decisions were also rendered in Denmark, Austria, Finland, Sweden, Italy and Spain.

The pemetrexed decisions have been reported here.  This Guest Kat is happy to now add a report to the list about the recent Dutch take on the pemetrexed saga.

Why the Court comes to a more limited scope of protection

A discussion of the scope of protection naturally starts with Article 69 EPC and the Protocol on the Interpretation of Article 69 EPC. Reasonable protection must be afforded to the patentee and at the same time a reasonable degree of legal certainty must be provided to third parties. It follows from Article 2 of the Protocol that due account shall be taken of any element which is equivalent to an element specified in the claims. So far the general introduction.

It was not in dispute in these proceedings that the literal wording of the claim leads to an extremely limited scope of protection (only covering pemetrexed disodium), and that the inventive concept behind the claim leads to an extremely broad scope of protection (not limited to pemetrexed disodium).  The inventive concept was considered not to be based on the choice of the salt but on therapeutic use of a combination of pemetrexed and vitamin B12 and, optionally, folic acid. As the benefits of the invention – reduced toxicity without negatively affecting efficacy – are not specific to pemetrexed disodium and could equally be achieved with a different pemetrexed salt, the skilled person would realize that the literal wording of the claim forms a limitation to the inventive concept. The question in these proceedings is how to find a reasonable scope of protection.

Factors that be taken into account

The Court first reiterates that the nature of the case should be considered when assessing scope of protection, including the technical advancement provided by the patented invention. Furthermore, a relevant factor is whether a specific scope of protection was deliberately chosen (this choice can be based on technical reasons, but this is not required, as will be explained below). If there was no such deliberate choice, a broad scope of protection is justifiable. However, if there is lack of clarity regarding the scope of the claim, this must be interpreted in the disadvantage of the patentee.

It is established Dutch case law that the prosecution file may be taken into account in the determination of the scope of protection. This can be done restrictively if this is to the advantage of the patentee, and can be done more liberally to the advantage of third parties.

Fair protection for Lilly’s patent

According to the Court, the overall disclosure of Lilly’s patent does not give any reason to believe that the inventive concept is limited specifically to pemetrexed disodium. On the other hand, the patent also does not encompass a clear indication that other salts are intended to be covered, other than is the case for vitamin B12 and the folium binding protein binding agent for which several different options are mentioned.

What, then, is fair and reasonable?
The Court has decided that Lilly’s patent is limited in scope specifically to pemetrexed disodium based on the following (jointly) decisive factors.

1. The skilled person will question the fact that no other pemetrexed variants are mentioned, given that it is “(childishly) easy” to manufacture other forms of pemetrexed. It was foreseeable at the priority date that there were other pharmaceutically suitable salts of pemetrexed and that these could be found routinely by the skilled person.

2. During examination that claim was limited from “antifolate” to “pemetrexed”. After this amendment some miscommunication took place between Lilly and the examiner. According to Lilly, the examiner indicated that the original application only provided basis for pemetrexed disodium, and limited the patent accordingly. However, according to the Court this is not what the examiner meant in his correspondence, and the skilled person would appreciate this. The Court emphasises that Lilly did not seek to clarify the situation with the examiner or contest the (misunderstood) allegation that the application did not have support for pemetrexed without the limitation to a specific salt.

3. Following the discussion with the examiner, Lilly simply limited the claim to pemetrexed disodium. Lilly also amended the description, making pemetrexed disodium the only embodiment instead of a preferred example. In the words of the Court, “Lilly did not attempt to include a sentence in the description such as: ‘as the skilled person will understand the invention can also be practised with other [ph]armaceutically acceptable salts’.” Lilly also accepted without any objection that the examiner limited other parts of the description to pemetrexed disodium. The icing on the cake was the following on file declaration by a representative of Lilly: “The Applicant seeks to draw a distinction between subject matter which is relevant to the invention which is indicated as being that to which “the present invention generally relates” and “the subject matter provided by the invention”.”

4. Lilly is a “pharmaceutical superpower” to which a considerable amount of expertise and experience with regard to filing patent applications can be attributed. A significant factor is that Lilly was not under time pressure during prosecution. Months have passed between the examiner’s communications and Lilly’s replies. Also, Lilly can still enjoy years of protection for (different salts of) pemetrexed based on EP 667 and a SPC still in force. To top things off, the Court refers to a third Lilly patent (EP 612) in which a very broad definition of pemetrexed is given, suggesting that Lilly is familiar with how to claim pharmaceutical compositions comprising pemetrexed.

5. The Court assumes that there was basis in the original PCT-application for more than pemetrexed disodium, and explicitly states that it did not assess the situation in which one would assume that there was no such basis, as this was not argued by either Lilly or Fresenius. However, the Court also states (“superfluously”) that even if this would have been the case the Court’s conclusion would remain the same. Other forms of pemetrexed equivalent to pemetrexed disodium were within reach of the skilled person at the priority date. If the PCT-application did not provide basis for those equivalents, it was Lilly who chose not to include them in the application. Even after being questioned about this at the hearing, Lilly did not state that the PCT-application contained a mistake or omission and that this was clear to third parties.

Hence, third parties confronted with the patent should be able to safely assume that Lilly deliberately limited the patent to pemetrexed disodium. The fact that there was no technical reason for Lilly to limit the patent to pemetrexed disodium does not change this conclusion. It would have been possible – and even obvious – for Lilly to have tried to obtain broader protection, and it did not. The underlying reasons for this decision are irrelevant. Now allowing a broader scope of protection would violate reasonable certainty for third parties, “which the factual judge must take into account as the countercheck”. Hence, there is also no room for the protection of equivalents that go beyond the use of pemetrexed disodium.

The three flavours of equivalence

The decision ends with a reference to the UK Patents Court decision of Mr Justice Arnold in Actavis v. Eli Lilly, in which it was held that “patentees resort to arguments about equivalents in three main classes of cases”:

- “The first is where, with the benefit of hindsight, it can be seen that the patent was unfortunately drafted, whether because of poor instructions from the inventor or poor drafting by his patent attorney or a combination of these things. Improver might perhaps be regarded as an example of this.”

- “The second class is where technology has moved on since the priority or filing date of the patent. Kirin-Amgen might perhaps be regarded as an example of this.”

- The third class is where the patentee now regrets a decision taken during the course of prosecution of the patent application, whether by himself or by the examiner, and is trying to avoid the consequences of that decision. As will appear, in my view the present case is a clear example of this.

Back in 2014, Mr Justice Arnold concluded that the pemetrexed patent fell under the third category, and the Dutch District Court of The Hague now agrees.

The Court reiterates that the doctrine of equivalence is not intended to bring subject matter within the scope of protection that was originally excluded on the basis of added matter objections. However, the Court adds, regardless of whether there was support in the original application or not, the doctrine of equivalence is in any event not intended to repair choices made during prosecution that the patentee in hindsight regrets, at the expense of legal certainty for third parties.

In summary

The District Court of The Hague shows no fear in diverging from a considerable body of foreign and domestic case law regarding the scope of protection of the pemetrexed patent. The Court provides detailed insight into its reasoning, which seems thorough and comprehensive.

Regardless of whether the Court’s reasoning in this decision is right or wrong – if there even exists such distinction when discussing scope of protection and equivalence – this Guest Kat welcomes the decision as a refreshing view on how to deal with issues of scope of protection and equivalence.

It remains to be seen, of course, how this will play out at the Court of Appeal of The Hague, assuming an appeal will be filed by Lilly."