A federal judge on Wednesday placed a temporary block on Colorado's first-in-the-nation effort to cap the price of Enbrel, Amgen Inc.'s biologic treatment for arthritis and plaque psoriasis. The injunction, issued by Chief Judge Daniel Domenico in the U.S. District Court in Denver, concluded that Amgen would likely suffer substantial and irreparable harm if the state imposed the price limit.
Domenico said in his ruling that the company could face damage to its ability to negotiate future contracts with wholesalers and distributors if forced to charge lower prices. He summarized the potential impact with a line emphasizing economic consequences: "as a matter of basic economic logic, Amgen is likely to be significantly harmed by a cap on the price of its product, even if the cap applies unevenly" within the supply chain.
The judge acknowledged Colorado's aim of improving patient affordability but wrote that the state could pursue other measures such as subsidies or negotiation strategies similar to those used by the federal government. He concluded that "capping the price of a patented drug" falls outside the state's permissible options, according to the opinion.
Background to the dispute dates to October, when the Colorado Prescription Drug Affordability Board set a cap on Enbrel at $600 for a 50-milligram weekly dose, which the board calculated at $31,200 annually. The cap was scheduled to take effect on January 1, 2027. By contrast, Enbrel's list price exceeds $100,000 per year. Amgen reported Enbrel sales of $2.23 billion in 2025, making the product one of the company's largest revenue generators.
Amgen argued in court filings that the state cap conflicted with federal patent law, violated the company's due process rights under the U.S. Constitution and risked undermining patient access to treatment. The company was given until July 5 to determine whether it would continue to supply Enbrel in Colorado should the injunction be lifted.
Colorado's Division of Insurance declined to comment on the matter, with spokeswoman Genna Morton saying the agency could not speak on pending litigation. Amgen and its attorneys did not immediately respond to requests for comment after the ruling.
The broader context noted in filings and the ruling is that the United States typically pays considerably more for branded medicines than other high-income countries, and policymakers at both the federal and state levels have been pursuing tools to restrain drug costs.
Domenico, who was appointed to the federal bench by President Donald Trump, has also been nominated by the president to serve on the 10th U.S. Circuit Court of Appeals, which covers Colorado.
Legal and market implications
The preliminary injunction preserves the status quo while litigation proceeds. The court's reasoning focuses on two core ideas identified in the order: (1) the likely economic harm to Amgen from a state-imposed cap on a patented product and (2) limits on a state's authority to impose that kind of pricing constraint when other policy avenues remain available. The litigation will determine whether the injunction becomes permanent or whether the state can proceed with its regulatory cap.
What remains unresolved
The ruling pauses implementation of Colorado's cap but does not finally decide the legal questions at issue. The state faces the choice of pursuing alternate affordability strategies or appealing the decision as the case moves forward.