Paris Court awards record damages of €28m over patent infringement in pemetrexed case

The provisional damages award by the Paris court against generic medicines manufacturer Fresenius Kabi is thought to be the highest of its kind ever ordered by any European court for patent infringement. The ruling is the latest in long-standing, multi-jurisdictional litigation between Eli Lilly and generic manufacturers in respect of Eli Lilly's patent rights for pemetrexed. Parallel proceedings have taken place in other European jurisdictions, including the UK, Germany, Italy, Belgium and The Netherlands.

The European patent in issue before the French court covers the use of the active ingredient pemetrexed disodium in combination with vitamin B12 or a pharmaceutical derivate thereof, for inhibiting tumour growth. This was formulated as a so-called Swiss type patent claim. Such claims relate to a new use of a previously known composition. Eli Lilly's branded product under the patent is called Alimta. It had sued Fresenius Kabi over its generic alternative, marketed as Pemetrexed Fresenius Kabi in France.

The claims of Eli Lilly's patent as initially filed referred to the use of antifolates, the class of compounds to which pemetrexed belong, but were limited during examination to pemetrexed. Following an objection from the examiner that Eli Lilly had added subject-matter it had not disclosed in the application as filed, Eli Lilly further limited the claims to pemetrexed disodium specifically.

At the crux of the dispute was the fact that the relevant claim in Eli Lilly's patent refers to the active ingredient pemetrexed disodium, and its product Alimta contains pemetrexed disodium. However, the Fresenius Kabi product is in a different salt form as it contains pemetrexed diacid. The generic manufacturer argued that this meant its product did not infringe Eli Lilly's patent. The French court disagreed, however, and found that the generic product did in fact infringe.

"Notwithstanding the extraordinary damages award, the court's reasoning on infringement was one of the most noteworthy aspects of this decision," said Jules Fabre, patent law expert at Pinsent Masons, the law firm behind Out-Law. 

In assessing the scope of the patent, and therefore whether Fresenius Kabi's product infringed, the court referred, as is common in such cases, to Article 69 of the European Patent Convention and the accompanying Protocol on Interpretation of Article 69. According to these provisions, whilst the claims of a European patent dictate the extent of protection, the description shall be used to interpret the claims.

In doing so, it concluded that the wording of the description of the patent was general enough to apply to more than one form of pemetrexed in combination with vitamin B12.

The court held that it is the combination of pemetrexed with vitamin B12 – used to significantly reduce side effects – which goes to the heart of the invention. It found that the form of the active ingredient – in this case the disodium salt – has no specific technical effect in the invention and would therefore be regarded as irrelevant by the skilled person.

In addition, the court rejected Fresenius Kabi's argument that by amending the claims during examination at the European Patent Office to refer to pemetrexed disodium specifically, Eli Lilly had waived protection in respect of products using other salts other that of pemetrexed.

The court, whilst recalling, in accordance with French case law, that the prosecution file history can be used as an additional source of interpretation, said that this is only an 'optional' tool, which is not binding on the court or the patentee. The court then made a distinction between amendments made to overcome a formal objection, such as an added matter issue as in the present case, and amendments made to circumvent a prior art document, such as an obviousness issue. It suggested that only the latter can be interpreted as a limitation of the scope of the patent.

The court therefore held that Fresenius Kabi's product literally infringed the patent.

Fabre said: "It is interesting, and perhaps surprising, to see that the court found literal infringement of Eli Lilly's patent. This is different to the courts in other jurisdictions in Europe where, although the courts still made an overall finding that Fresenius Kabi's product infringed the patent, infringement was found on the basis of the so-called doctrine of equivalents and not literally, given the narrow wording of the claims."

A permanent injunction was ordered against Fresenius Kabi, and provisional damages amounting to €28m – a new record for patent infringement – were awarded, pending final determination.

More specifically, the court awarded €8m to Eli Lilly, the patentee, for patent infringement, on the basis of a 25% royalty rate, and €20m to Lilly France, the distributor in France, for unfair competition, on the basis of lost profits.

The judgment is subject to an appeal.