The Federal Trade Commission has brought an administrative complaint against three of the country's largest pharmacy benefit managers (PBMs), accusing them of engaging in practices that artificially inflated the list price of insulin drugs.

The FTC said CVS Caremark, Cigna’s Express Scripts, and UnitedHealth’s OptumRx profit at the expense of patients forced to pay more for insulin.

Months earlier, the agency released a report alleging the companies drove up the costs of some medications, including insulin.