Background
Colorado enacted a groundbreaking pharmaceutical pricing law through its Prescription Drug Affordability Review Board (PDAB), which is authorized to cap the prices that drug manufacturers can charge for certain high-cost medications. In one of its first exercises of that authority, the PDAB selected Enbrel (etanercept), a biologic used to treat rheumatoid arthritis and other autoimmune conditions, as a target for price regulation. Enbrel’s current list price exceeds $100,000 per year; Colorado’s proposed cap would limit its price to approximately $31,200 per year for a 50mg weekly dose — a reduction of roughly 70% — effective January 1, 2027.
Amgen Inc., which holds patents on Enbrel and markets it in the United States, sued Colorado in federal court arguing that the price cap law is preempted by federal patent law, violates due process, and threatens the viability of ongoing drug development and distribution agreements. Amgen moved for a preliminary injunction to block the price cap from taking effect while the case proceeds to a final merits decision.
The Court’s Holding
Chief Judge Daniel Domenico granted Amgen’s motion for a preliminary injunction. The court found that Amgen satisfied all four preliminary injunction factors: likelihood of success on the merits, irreparable harm, balance of equities, and public interest.
On likelihood of success, Judge Domenico’s analysis turned on the relationship between federal patent rights and state price regulation. The court’s reasoning centered on a core proposition: federal patent law grants the patent holder the exclusive right to exclude others from making, using, selling, or offering for sale the patented invention — and that exclusive right necessarily includes the right to set the price of the patented product. A state law that caps the price at which a patented drug can be sold directly conflicts with this federal grant by eliminating the patent holder’s ability to extract the market value that the exclusivity right is designed to provide. In the court’s formulation, while Colorado may pursue drug affordability goals through subsidies, price negotiations, or other means, “capping the price of a patented drug is not an option.”
On irreparable harm, the court found that even if the immediate financial impact of a 70% price reduction were somehow quantifiable, the harm to Amgen’s contractual relationships with wholesalers and distributors — built around the existing price structure — could not be fully remedied by money damages after the fact. The balance of equities favored Amgen because Colorado’s price cap law, even if eventually upheld, would not take effect until January 2027, so delaying its implementation while the legal questions are resolved causes the state only minimal harm. The public interest similarly supported the injunction: forcing a major biologic off the market or into supply disruptions pending litigation would harm patients who depend on Enbrel.
Key Takeaways
- Federal patent law preempts state drug price cap statutes, at least at the preliminary injunction stage — a first-of-its-kind judicial holding that directly constrains the growing state movement to regulate prescription drug prices through affordability review boards.
- The patent holder’s right to set price is treated as part of the federal “patent bargain” — in exchange for public disclosure, the inventor gets a time-limited monopoly that includes control over pricing, and states cannot override that federal grant.
- At least twelve states have enacted similar PDAB-style drug pricing review laws; this ruling puts all of them on notice that their price-capping authority may be preempted when the targeted drug is under patent protection.
- The ruling is a preliminary injunction, not a final merits decision — the preemption question will be fully briefed and decided later. But the court’s language (“capping the price of a patented drug is not an option”) signals a strong view on the merits.
Why It Matters
The intersection of pharmaceutical patent law and state drug affordability regulation is one of the most consequential IP policy questions of the decade. States frustrated by the failure of federal legislation to address drug pricing have turned to their own PDAB mechanisms, and Enbrel — a drug that generated over $4 billion in U.S. revenue before biosimilar competition eroded its market — was a natural target for Colorado’s inaugural exercise of price-cap authority.
Judge Domenico’s ruling, if affirmed on full briefing and on any eventual appeal, would significantly constrain state authority to regulate prices for on-patent biologics and small-molecule drugs. The logic of the preemption argument extends beyond Enbrel to any drug protected by an active patent — potentially immunizing the most expensive drugs (those still under patent, before generic or biosimilar competition) from exactly the state-level price controls that reformers most want to apply to them. The case will be closely watched by pharmaceutical companies, state health agencies, and Congress as a bellwether for the scope of federal patent preemption in the drug pricing space.