Jury Issues Mixed Ruling in Regeneron v. Amgen Case

Case Background

This case arose under federal antitrust law, with additional claims based on unfair competition and tortious conduct.  The Plaintiff, Regeneron Pharmaceuticals, Inc., filed the complaint in the United States District Court for the District of Delaware.  The issue involves Regeneron's cholesterol-lowering medicine, Praluent (alirocumab), and its direct competitor, Repatha (evolocumab), which was manufactured and distributed by the Defendant, Amgen Inc.  Regeneron claimed that Amgen used exclusionary and anticompetitive practices to remove Praluent from the market in order to maintain and expand Amgen's monopoly position in the market for PCSK9 inhibitors critical drugs used to lower LDL-C or "bad cholesterol" in high-risk patients.

Events That Led to the Dispute:

Regeneron had introduced Praluent as the first FDA-approved PCSK9 inhibitor in 2015. Around the same time, Amgen had also launched Repatha, a similar but structurally distinct drug. Both had competed for the same high-risk cardiovascular patient population. Amgen had initially tried to eliminate Praluent through an aggressive patent litigation campaign, seeking a court injunction to bar its sale. When the courts had invalidated Amgen’s patents ruling that they had overreached by claiming millions of antibody compounds they had not invented Amgen had turned to commercial tactics. It had allegedly devised an anticompetitive bundling scheme that tied discounts on its high-revenue, unrelated drugs (like Otezla and Enbrel) to exclusive or near-exclusive formulary placement of Repatha over Praluent. Amgen’s strategy had threatened third-party payors with financial penalties if they included Praluent on their formularies, thereby locking Regeneron out of critical segments of the market.

Injuries Suffered

As a direct result of Amgen’s alleged conduct, Regeneron had suffered significant and multifaceted injuries. The exclusionary bundling had slashed Praluent's market share and had rendered its continued commercialization financially unviable. Sales had plummeted due to blocked access to major pharmacy benefit managers (PBMs) and Medicare Part D plans, which had excluded Praluent from their formularies or imposed restrictive prior authorization. Regeneron had been forced to eliminate its sales force for Praluent, cut future R&D investment, and curtail marketing expenditures. The cumulative effect had not only damaged the company financially but also diminished its competitiveness and harmed patients who had benefited from the unique safety and efficacy profile of Praluent.

Damages Faced

Regeneron had forecasted a net financial loss on Praluent in 2022 for the first time since the drug had launched, attributing the downturn entirely to the anticompetitive marketplace conditions allegedly engineered by Amgen. The bundling scheme had made it economically impossible for Regeneron to offer competitive rebates on Praluent without incurring unsustainable losses. Moreover, the artificial exclusion had limited prescriber access, reduced patient options, and chilled future innovation in the PCSK9 inhibitor space. Regeneron had claimed not only financial injury but also competitive and reputational harm, asserting that Amgen’s tactics had long-term consequences for drug market dynamics and patient welfare.

KEY ARGUMENTS AND PROCEEDINGS

LEGAL REPRESENTATION

Plaintiff(s):     Regeneron Pharmaceuticals, Inc.

• Counsel for Plaintiff(s): David E. Wilks| Scott B. Czerwonka|

• Expert for Plaintiff(s):  Divya Mathur | Robert H. Eckel | Fiona Scott Morton | Heather Bates

 Defendant(s): Amgen Inc.

• Counsel for Defendant(s): Ashley E. Johnson | Stephen Weissman | Eric J. Stock | Ben A. Sherwood | Melanie K. Sharp | James L. Higgins | Taylor E. Hallowell

Claims Asserted

Regeneron had proclaimed multiple claims against Amgen, in both federal and state antitrust statutes. It had alleged violations of Section 2 of the Sherman Act for monopolization and attempted monopolization, as well as anticompetitive tying and bundling practices. Regeneron had also asserted claims under Section 1 of the Sherman Act and Section 3 of the Clayton Act for unlawful exclusionary agreements. Additionally, the complaint had included claims of unfair competition and tortious interference under state law. Regeneron had requested injunctive relief to halt Amgen’s bundling practices, treble damages under the Clayton Act, attorneys’ fees, and a jury trial.

Defense

The Defendants denied all wrongdoing. They argued they had followed the law and met their obligations. They said the Plaintiff’s claims were exaggerated, unsupported by reliable evidence, or caused by other factors outside their control. Their attorneys told jurors that the Plaintiff failed to prove a direct connection between the Defendants’ actions and the alleged harm. They also claimed the Plaintiff’s own conduct, and in some instances third parties’ actions, played a major role in the losses. The defense stressed that the Plaintiff sought damages far beyond what was reasonable and that much of the case relied on speculation rather than solid proof.

Jury Verdict

On May 15, 2025, the jury returned its decision after deliberating on all claims. The panel answered each question on the verdict form, deciding which claims succeeded, which failed, and whether damages should be awarded. In some instances, the jury found the Defendants liable but awarded no money, concluding that the Plaintiff had not proven actual financial loss from that conduct. For other claims, the jury either found no liability or determined that damages were not justified. The final verdict reflected a mixed outcome, with the defense prevailing on significant portions of the case and limiting or eliminating potential damages on others.

Court documents are available upon request at jurimatic@exlitem.com