On 12 March 2026, Juve Patent reported that Sanofi/Regeneron and Amgen “have apparently settled” their dispute over PCSK9 inhibitors Praluent® (arilocumab) and Repatha® (evolocumab). No announcements have been made by the companies and there are no details available regarding the terms of any settlement.
The dispute dates from at least 2014, when Amgen commenced US litigation against Sanofi/Regeneron, alleging that Praluent® infringed genus claims of Amgen’s patents relating to Repatha®. In January 2017, the US District Court in Delaware granted Amgen’s request for a permanent injunction prohibiting Sanofi/Regeneron from infringing two of Amgen’s Repatha® patents. However, in May 2023, the US Supreme Court published its decision affirming a ruling of the Federal Circuit Court that the genus claims of Amgen’s Repatha® patents were invalid for lack of enablement.
Since 2014, there have been numerous battles between Sanofi, Regeneron and Amgen in relation to the PCSK9 inhibitors in courts and patent offices around the world. For example:
- In 2019, the Düsseldorf Regional Court found that Praluent® infringed Amgen’s EP2215124, relating to Repatha®, and granted an injunction preventing Sanofi from manufacturing, selling or marketing the drug in Germany. This decision was later overturned as a result of restriction of the claims of the relevant patent by the European Patent Office;
- Sanofi/Regeneron filed a patent revocation action on the date of the UPC’s commencement, 1 June 2023, with Amgen filing an infringement action on the same day. On 16 July 2024, the Munich Central Division of the UPC declared Amgen’s evolocumab patent EP3666797 invalid, based on lack of inventive step;
- in Australia, following long-running oppositions in the Australian patent office decided in favour of Amgen, on 23 April 2025, the Federal Court confirmed that five of Amgen’s evolocumab-related patent applications were valid and should proceed to grant;
- in May 2025, a jury of the US District Court for the District of Delaware found that Amgen had breached antitrust and tort laws by using cross-therapeutic bundling rebates, involving its anti-inflammatory drugs Enbrel® (etanercept) and Otezla® (apremilast), to convince pharmacy benefit managers (PBMs) to choose Repatha® (evolocumab) as their exclusive PCKS9 product, instead of Regeneron’s Praluent® (alirocumab). The jury awarded Regeneron US$135.6 million in compensatory damages and $271.2 million in punitive damages.
The settlement is expected to result in the withdrawal by Sanofi, Regeneron and Amgen of various oppositions to patent applications in the European Patent Office and any appeals and proceedings which remain pending in relation to Repatha® and Praluent®.