Sanofi and Regeneron have lost their infringement case against Amgen in the Unified Patent Court’s first ruling on a second medical use claim, though their patent was upheld as valid. The court found no evidence that Amgen’s cholesterol drug Repatha was being prescribed off-label for the patented use, nor that Amgen knew — or should have known — about such prescriptions. The judgment sets an early precedent that to prove infringement, rights holders must show not just potential, but actual or likely off-label use and the alleged infringer’s awareness of it.
The Unified Patent Court this week handed down its first judgment on the infringement of a second medical use pharmaceutical patent claim, offering long-awaited guidance on how such claims — made to protect the use of a known substance for treating a new medical condition — will be handled under the new UPC system.Sanofi Biotechnology and Regeneron Pharmaceuticals’ complaint against Amgen Inc. and its European subsidiaries was dismissed by the Düsseldorf Local Division this week (see here), marking a precedent for how the UPC approaches disputes over off-label use. Amgen’s counterclaim for revocation was also dismissed.
The decision shows that to succeed in a second medical use claim, an innovator must show that the alleged infringer’s product is not only capable of being used according to the patent, but is in fact being prescribed that way, or is likely to be, and that the manufacturer knows or should know that this is happening.
“For a finding of infringement of a second medical use claim, the alleged infringer must offer or place the medical product on the market in such way that it leads — or may lead — to the claimed therapeutic use of which the alleged infringer knows or reasonably should have known that it does,” according to the ruling, led by presiding judge Ronny Thomas.
“The requirements of such behavior cannot be defined in an abstract manner, but require an analysis of all relevant facts and circumstances of the patent claim in question.”
The parties may decide to appeal the court’s decision. This means that the Court of Appeal may still rework the UPC’s approach to second-medical-use patents.
The case concerns Regeneron’s EP 3,536,712, which relates to therapeutic treatments for diseases associated with elevated lipoprotein levels, such as coronary artery disease.
Sanofi and Regeneron accused Amgen’s cholesterol-lowering drug Repatha of infringing the second-medical-use claim and sought injunctive relief, disclosure, recall of infringing products, and damages across five EU member states.
Amgen denied infringement and filed a counterclaim seeking full revocation of the patent, challenging its validity and inventive step. Sanofi and Regeneron also submitted auxiliary requests to maintain amended claims in case the patent was partially invalidated.
The UPC ultimately rejected Amgen’s invalidity counterclaim, finding the patent valid. The judges concluded that the core invention — identifying specific antibodies that block a protein linked to cholesterol levels — was sufficiently disclosed and enabled for skilled scientists to reproduce without undue burden.
The court found no infringement. Repatha’s Summary of Product Characteristics, or SmPC, did not induce physicians to prescribe the drug off-label for reducing Lp(a) — the therapeutic use claimed in the patent.
Sanofi and Regeneron also failed to show that such prescriptions were occurring, were likely to occur, or that Amgen knew — or should have known — about such use, the court found.
“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,” the ruling said. “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.”
Legal experts say the judgment brings valuable clarity, but also highlights lingering uncertainty around remedies in second medical use cases.
One key question left open is how damages should be calculated if infringement is eventually found. If based on the innovator’s lost sales, damages could far exceed the generic manufacturer’s profits, especially in cases involving sharp price drops after market entry.
For innovator companies, the ruling implies the need to gather concrete evidence of off-label prescription and the competitor’s knowledge to support second medical use claims. Only potential for such use is not enough.
For generics and biosimilars, the decision offers reassurance that compliant marketing alone won’t automatically trigger infringement, but attention to product labeling and promotional materials will be important.
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