The Federal Trade Commission on Friday filed an administrative complaint against the three largest pharmacy benefit managers and their affiliated group purchasing organizations, alleging they have contributed to high insulin prices through anti-competitive practices.

The FTC claims CVS Health's Caremark, Cigna's ESI and United Health Group's OptumRx created a "perverse drug rebate system," resulting in higher insulin list prices. Despite lower list-price insulins becoming available, the PBMs excluded those options for patients and provided higher prices and highly rebated insulin products, the agency alleges.