The Court of Milan rules on infringement by equivalence and the relevance of the patent’s file history
By order dated 20 September 2018 (docket no. 45209/2017), ruling on the appeal of the first instance preliminary decision, the Court of Milan ascertained – within the limits of interim proceedings – the infringement by equivalence of Eli Lilly’s patent EP 1313508, concerning an anti-cancer drug named Alimta, which contains pemetrexed disodium. The Court overturned the first instance decision, rejecting the request of its competitor – the Fresenius Kabi Company – for a declaration of non-infringement of the patent at issue.
Specifically, Eli Lilly claimed the infringement of its product by Fresenius’ equivalent drug, although the latter was composed of pemetrexed in the form of diacid instead of disodium. Eli Lilly based its claim on the doctrine of infringement by equivalence, according to which it is possible to extend the scope of a patent beyond the exact wording of the claims, including non-integral implementations of the invention in which all the key elements of the patent are retained.
According to the first instance judge, the different forms of the two compounds prevented Fresenius’ drug, although performing the same function, from being a counterfeit of Eli Lilly’s drug. On the contrary, according to the order at issue, the form of the active substance of pemetrexed is a non-essential element of the patented invention, since the latter does not concern the specific form of pemetrexed, but the reduction of the toxic effects thereof obtained by associating pemetrexed with vitamin B12. The anti-toxic effect is therefore obtained regardless of the pharmaceutical form of the pemetrexed.
In this context, in order to determine whether or not there was infringement by equivalence, the Court applied the so-called “triple test” and ascertained that: i) Eli Lilly’s and Fresenius’ drugs perform the same function (in fact they are both anti-cancer antifolates); ii) they have the same modus operandi (because the active substance of the two compounds is the same (the pemetrexed); iii) they achieve the same result (the reduction of the toxic effects of the drug thanks to its combination with vitamin B12).
The decision also focused on the relevance of the patent’s file history for the purpose of determining its scope of protection. According to the judge of first instance, the limitation of the patent to pemetrexed in the form of disodium, during the relevant prosecution, prevented Eli Lilly from claiming – by invoking the aforesaid principle of equivalence – a wider scope of protection before the court, extending to other pharmaceutical forms of the same active substance. The panel of judges handling the preliminary appeal instead recalled that the scope of protection of a patent must be reconstructed with main reference to the claims, while the examination of its file history – which is “secondary and ancillary” – could be useful to circumscribe the scope of the patent only in the event that its object has been limited to overcome objections concerning its novelty or inventive step. However, in the case at issue, it was clear that Eli Lilly had limited the object of the patent to pemetrexed disodium only to obviate the formal objections of the EPO examiner. Thus, the aforesaid amendments could not prevent the extension of the scope of protection to equivalent forms of pemetrexed.
The Court of Milan therefore ascertained the infringement by equivalence of Eli Lilly’s product and consequently inhibited the production and marketing of the counterfeit product, ordering it to be recalled from the market.