Context: French pharma giant Sanofi and its rival Amgen have been embroiled in patent infringement litigation over their respective cholesterol-lowering drugs, Praluent and Repatha, for over 10 years (Amgen first sued Sanofi and Regeneron in the U.S. in 2014). In another recent prong of the dispute, Sanofi sued Amgen in the Unified Patent Court’s (UPC) Dusseldorf Local Division (LD) over the alleged infringement of EP3536712 (“Methods for reducing lipoprotein(a) levels by administering an inhibitor of proprotein convertase subtilisin kexin-9 (pcsk9)”). In parallel opposition proceedings in the European Patent Office, which issued a preliminary opinion on August 12, 2024, the patent-in-suit was upheld. An oral hearing was held on February 25, 2025.
What’s new: In a decision handed down today, the Dusseldorf Local Division dismissed Sanofi’s infringement claim, ruling that the claimant did not sufficiently prove that doctors prescribe Amgen’s drug Repatha for non-label use (May 13, 2025 UPC decision (PDF)). The LD also dismissed Amgen’s counterclaim for revocation.
Direct impact and wider ramifications: This ruling marks the first time the UPC has issued a decision on how to deal with second medical use. While the list is not exhaustive, it does contain key considerations that the UPC may make when ruling over second medical use patent infringement cases. As Sanofi’s patent has been upheld, it will likely file an appeal, which is, after all, only an LD decision. A potential appellate decision on these key second medical use questions will be vital for the development of the UPC’s case law.
In an initial preliminary objection, Amgen had argued that the UPC does not have international jurisdiction to decide on the alleged infringement of the patent-in-suit in Germany in light of parallel national infringement proceedings brought by Sanofi and currently pending in the national District Court in Düsseldorf. This was withdrawn, however, during the oral hearing in February.
In its decision today, the Dusseldorf LD found not only that the UPC did have jurisdiction, but that all the parties involved had the right to sue over the patent in question.
The court also dismissed Amgen’s claims that Sanofi’s patent was invalid, outlining two key scenarios in which the therapeutic use of a second medical use patent is valid as it potentially involves an inventive step:
- a new indication, e.g. a disease not yet treated by the claimed substance, or
- an indication for a new group of patients.
The LD also concluded that Sanofi had not done enough to convince it that there was significant activity from doctors prescribing Amgen’s drug Repatha for non-label use:
“The Court finds that the evidence does not prove a likelihood that physicians will prescribe the contested embodiment for use in reducing Lp(a) levels. Even the Claimant´s expert only refers to an “expectation” that a concomitant (with LDL-C level) elevated Lp(a) level is often also taken into consideration. This is contradicted by the Defendants` experts.”
Because there is no existing case law in the UPC over the infringement of second medical use claims, the LD listed several relevant facts that it included in its analysis and will do moving forward (but won’t necessarily limit itself to):
- the extent or significance of the allegedly infringing use;
- the relevant market, including what is customary on that market;
- the market share of the claimed use compared to other uses;
- what actions the alleged infringer has taken to influence the respective market:
- either “positively”, de facto encouraging the patented use; or
- “negatively” by taking measures to prevent the product from being used for patented use.
The court also noted that for a finding of infringement of a second medical use claim, there must be either a prescription (for the infringer’s product) to treat hypercholesterolemia or circumstances showing that such a use may be expected to occur. The alleged infringer should also know this, or have “reasonably” known, the LD has ruled.
Panel and counsel
Panel: Presiding Judge Ronny Thomas, Judge Dr Bérénice Thom (and here, judge-rapporteur), Judge András Kupecz, and Technically Qualified Judge Xavier Dorland-Galliot.
Counsel for Sanofi Biotechnology and Regeneron Pharmaceuticals: Hoffmann Eitle’s Dr Niels Hölder, Mike Gruber, and Dr Michael Pfeifer, as well as Carpmaels & Ransford LLP’s Daniel Wise and Agathe Michel-de Cazotte.
Counsel for Amgen: Bardehle Pagenberg’s Johannes Heselberger and Nadine Westermeyer.