How a drug company made $114 billion by gaming the US patent system

The incident has become a case study in how drug companies artificially prop up prices of their best-selling drugs

In 2016, a blockbuster drug called Humira was poised to become a lot less valuable.

The key patent on the best-selling anti-inflammatory medication, used to treat conditions like arthritis, was expiring at the end of the year. Regulators had blessed a rival version of the drug, and more copycats were close behind. The onset of competition seemed likely to push down the medication’s $50,000-a-year list price.

Instead, the opposite happened.

Through its savvy but legal exploitation of the US patent system, Humira’s manufacturer, AbbVie, blocked competitors from entering the market. For the next six years, the drug’s price kept rising. Today, Humira is