Costly prescription drugs can keep people from necessary treatment and from managing their health effectively. In addition to several strategies adopted by federal and state officials, competition amongst drug products — including expanded access to generic drugs that cost consumers up to 85% less than brand-name drugs — can help lower prescription drug costs and increase access to medications. But brand-name drug manufacturers employ various tactics, including improper patent listing and legal challenges, to extend exclusivity periods that prevent generic products from entering the market. This Expert Column discusses the Federal Trade Commission’s (FTC) ongoing efforts to address these abuses, as well as the latest developments in litigation over improper patent listings that delay access to generic drugs.
Background
When a pharmaceutical manufacturer creates a unique drug, the manufacturer receives exclusive patent rights to make, use, and sell the drug for a limited time. These exclusive rights ideally incentivize drug companies to invest in the development of new medications by allowing them to operate without competition for a specified period. Because of the lack of competition, brand-name drugs tend to be expensive and often unaffordable for many consumers.
To help balance innovation and affordability, the Drug Price Competition and Patent Term Restoration Act of 1984 — commonly known as the Hatch-Waxman Act — provides brand-name manufacturers with limited exclusivity periods, while facilitating the approval process for generic drugs following such exclusivity periods. Brand-name drug manufacturers that want to market a new drug must submit a New Drug Application (NDA), including the results of extensive clinical trials to assess the drug’s safety and efficacy, to the Food and Drug Administration (FDA). A drug’s exclusivity depends on its type. New drugs, once approved, are granted at least a five-year exclusivity period during which no other brand-name or generic drug using the same active ingredient can be marketed, with longer or shorter exclusivity periods for certain types of drugs.
To help bring generic drugs to market more quickly, the Hatch-Waxman Act created an expedited pathway that allows generic drug manufacturers to rely on the clinical trial data from the underlying brand-name drug when applying for approval via an Abbreviated New Drug Application (ANDA). Generic drug manufacturers can submit an ANDA before any brand-name patents have expired by showing that the related patent listing is either invalid or unenforceable.
The FDA lists approved drugs and their patents, as well as their generic equivalents, in the so-called Orange Book, a publication titled “Approved Drug Products with Therapeutic Equivalence Evaluations.” If a patent for a specific drug is listed in the Orange Book, the FDA cannot approve any related ANDA for 30 months. Given this exclusivity protection, some brand-name drug manufacturers have used the Orange Book publication process to block generic competition by listing improper or invalid patents. Doing so is possible because the FDA does not assess patent listings for technical validity; in most cases, the patent’s validity is never called into question until it is the subject of a lawsuit.
Questions about patent validity typically arise when a brand-name drug manufacturer sues a generic drug manufacturer for patent infringement. In most cases, brand-name manufacturers allege that the generic drugs unlawfully use or contain ingredients covered by their patents. Generic drug manufacturers counter that the brand-name manufacturers’ patents listed in the Orange Book are invalid and therefore cannot be infringed.
FTC Action on Delayed Access to Generic Drugs
Recognizing the anticompetitive nature of these delay tactics, the FTC has long asserted that such patent abuses could violate the Sherman Act — a law that prohibits monopolies and unfair trade restrictions. In the early 2000s, the FTC studied the prevalence of delay tactics by brand-name drug manufacturers and identified several instances in which companies had listed additional patents to extend the 30-month exclusivity period for new ANDAs. In some of these instances, courts found the additional listed patents to be improper.
More recently, the FTC scrutinized Orange Book-related practices and other tactics that delay the entry of generic competition. In 2023, the FTC issued a policy statement condemning the use of improper listings and said it intended to scrutinize improper listings as unfair or deceptive acts. This was followed by the FTC’s challenge to more than 100 patents held by 10 companies, alleging they were improperly or inaccurately listed in the Orange Book. In 2024, this list was expanded to include more than 300 improper or inaccurate Orange Book listings.
FTC’s leadership on improper listings has continued under the Trump administration. In May 2025, the FTC issued an additional round of warning letters to challenge more than 200 patents and urged brand-name drug manufacturers to delist any improper patents or certify that they meet the requirements for Orange Book listing. During this round of action, the FTC sent warning letters to seven entities with patent listings across 17 different brand-name products. The FTC, alongside the Department of Justice, also held a series of listening sessions to discuss ways to make prescription drugs more affordable by promoting competition; these sessions included several panels dedicated to addressing anticompetitive concerns from improper Orange Book listings. These listening sessions will inform a formal report on anticompetitive practices in the pharmaceutical market.
Collectively, the FTC’s actions have led to the delisting of patents that could encourage generic competition. For instance, the actions taken by the FTC under the Biden administration led to the delisting of patents across 22 different brand-name products.
Recent Developments in Orange Book Litigation
Courts have also upheld the FTC’s challenges to improperly listed patents, and the FTC has filed briefs in other litigation over such listings. In 2024, the FTC filed an amicus brief before the Court of Appeals for the Federal Circuit in a lawsuit filed by Teva Pharmaceuticals, a brand-name drug manufacturer, against Amneal Pharmaceuticals, a generic manufacturer, for infringement of one of Teva’s patents for an asthma inhaler. Teva’s patent does not involve the inhaler’s active ingredient but rather the mechanical device through which the active ingredient is administered. Amneal counterclaimed, arguing that Teva’s patent listing was improper. (The FTC also filed an amicus brief before the district court and previously challenged the relevant Teva patents through the FDA’s Orange Book dispute process.)
The district court ruled for Amneal, ordering Teva to delist its patent. The Federal Circuit affirmed, reasoning that a patent does not properly claim a drug without at least claiming the drug’s active ingredient. Echoing the FTC’s amicus brief, the Federal Circuit emphasized that devices that simply contain an active ingredient do not qualify as drugs and therefore do not meet the requirements for listing in the Orange Book. The Federal Circuit also denied Teva’s request for rehearing. Although Teva was expected to appeal the decision to the Supreme Court, it did not.
The Federal Circuit’s decision in Teva v. Amneal is one of the few cases in which a federal appellate court has addressed the issue of improper Orange Book listings. But more district court decisions and appeals are on the horizon. In 2021, Jazz Pharmaceuticals, a brand-name manufacturer, alleged that Avadel Pharmaceutical filed an NDA that would infringe on Jazz’s patent for Xywav, a medication to treat idiopathic hypersomnia that can cost nearly $200,000 per year. Jazz’s patent claims a method of distribution for the drug, not anything inherently novel about the drug or its use. There, too, the FTC filed an amicus brief calling for Jazz’s patent to be delisted. The FTC reiterated that the Hatch-Waxman Act limits patent listings to claims for a drug or method of using a drug — and does not extend to patents on a distribution method. As the FTC emphasized, allowing patents to be listed for logistical processes would open the door to countless instances of leveraging the Orange Book to block generic competition. After multiple decisions by the district court and the Federal Circuit, both parties agreed to dismiss the case.
In yet another Orange Book case, the FTC filed an amicus brief ina 2023 lawsuit by Mylan, a generic drug manufacturer, alleging that Sanofi, a brand-name drug manufacturer, improperly shielded its insulin medications from competition, including by improperly listing patents for two injectable forms of insulin in the Orange Book. Mylan seeks the delisting of Sanofi’s patents, arguing that many are invalid. This litigation is still ongoing. These and other lawsuits on improper patent listings could soon reach the Federal Circuit and, potentially, the Supreme Court.
What’s Next?
The FTC has the authority to address improper patent listings that delay access to generic drugs — from issuing direct challenges to sending warning letters to filing amicus briefs. The FTC has continued to take action to address improper Orange Book listings and pave the way for more generic competition, which may consequently help shore up efforts to lower prescription drug costs for patients. At the same time, litigation over improper patent listings is expected to continue and will eventually result in additional appellate decisions — with significant consequences for patent abuses that keep affordable medicines out of the hands of those who need them.
DISCLAIMER: The views and opinions expressed in this piece are those of the author and do not reflect the views of the O’Neill Institute.
