Lina Khan, Chair of the Federal Trade Commission (FTC), testifies before the House Appropriations Subcommittee at the Rayburn House Office Building on May 15, 2024 in Washington, DC.

The Federal Trade Commission on Friday sued three large U.S. health companies that negotiate insulin prices, arguing the drug middlemen use practices that boost their profits while "artificially" inflating costs for patients.

The suit targets the three biggest so-called pharmacy benefit managers, UnitedHealth Group's Optum Rx, CVS Health's Caremark and Cigna's Express Scripts. All are owned by or connected to health insurers and collectively administer about 80% of the nation's prescriptions, according to the FTC.

The FTC's lawsuit also includes each PBM's affiliated group purchasing organization, which brokers drug purchases for hospitals and other health-care providers. The agency said it could recommend suing drugmakers Eli Lilly , Sanofi and Novo Nordisk in the future as well over their role in driving up list prices for their insulin products.

A UnitedHealth spokesperson said the suit "demonstrates a profound misunderstanding of how drug pricing works, noting that Optum RX has "aggressively and successfully" negotiated with drug manufacturers.

A CVS spokesperson said Caremark is "proud of the work" it has done to make insulin more affordable for Americans, adding that "to suggest anything else, as the FTC did today, is simply wrong."

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