By Rebecca Robbins @ NYTimes.com, Jan. 28, 2023

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 U.S. 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 the most lucrative franchise in pharmaceutical history.

Next week, the curtain is expected to come down on a monopoly that has generated $114 billion in revenue for AbbVie just since the end of 2016. The knockoff drug that regulators authorized more than six years ago, Amgen’s Amjevita, will come to market in the United States, and as many as nine more Humira competitors will follow this year from pharmaceutical giants including Pfizer. Prices are likely to tumble.

The reason that it has taken so long to get to this point is a case study in how drug companies artificially prop up prices on their best-selling drugs.

AbbVie orchestrated the delay by building a formidable wall of intellectual property protection and suing would-be competitors before settling with them to delay their product launches until this year.

The strategy has been a gold mine for AbbVie, at the expense of patients and taxpayers.[....]