The Humira Patent Thicket, the Noerr-Pennington Doctrine, and Antitrust's Patent Problem

Since its approval by the U.S. Food and Drug Administration (FDA) in 2002, the drug Humira® (adalimumab) has been one of the best-selling drugs in the U.S. and around the world. In 2021 alone, Humira generated $20.7 billion in revenue for its manufacturer, AbbVie, Inc. Humira is also very expensive, costing patients approximately $78 000 per year, a price which AbbVie has continued to increase year after year. This is particularly unaffordable as Humira is used to treat many chronic conditions – including rheumatoid arthritis, Crohn’s disease, and ulcerative colitis – which require patients to take Humira for extended periods of time.<br><br>Humira remains a high-priced drug today even though its core patent (patent ‘382) expired in 2016. Typically, expiration of the core patent on a biologic will allow entry of biosimilars into the market, which will result in a substantial price reduction, but this has not yet happened with Humira.<br><br>The explanation for this lack of competitive entry is that AbbVie was granted many additional (late-stage) patents on Humira, including patents on methods for manufacturing, its formulation, and potential future formulations. AbbVie applied for approximately 247 patents, of which 132 were granted, creating a “patent thicket” protecting Humira from competition until 2037 (when the last patent will expire). Notably, 90 percent of these patent filings were after Humira was already on the market, and almost half were filed in 2014 or later, in advance of the expiration of its core patent ‘382.<br><br>With this extensive patent protection, it became virtually impossible for biosimilar companies to gain approval to enter the market without potentially infringing one or more of the Humira patents. Instead of prolonging expensive litigation claiming that Humira’s patents were not infringed by the biosimilar application, virtually all the biosimilar companies settled with AbbVie prior to market entry. These settlements permit the biosimilars to enter the U.S. market early in 2023 – prior to the expiration of the last patent in 2037 – but require payment of royalties to AbbVie for a period after market entry. Some settlements also allow biosimilar companies to enter the European market, the earliest in October 2018.