WASHINGTON, (Reuters) – Senators Maria Cantwell and Chuck Grassley introduced a bill Tuesday giving the U.S. Federal Trade Commission greater power to control pharmacy benefit managers who administer prescription plans. Cantwell’s office stated that this would be a major change.

Legislators from both sides are concerned about the high costs of medical bills, as well as rising prices for older medications like insulin.

Senator Cantwell said in a statement that “the rising costs of prescription drugs have a devastating impact on the pockets of American consumers.” “PBMs are the middlemen in the prescription drug supply chain and it’s time for Congress to give the FTC the ability to shine a brighter light on any deceptive and abusive practices.”

Senator Grassley claimed that many of his constituents were unhappy about high drug prices.

In a statement, he stated that Congress must direct the Federal Trade Commission’s pursuit of these deceptive and arbitrary practices.

It would prohibit unfair pricing practices and mandate reports to FTC concerning spread pricing. This is where the PBM pays one price for a pharmacy but charges the individual’s health insurance at a higher rate.

Cantwell’s office reports that nearly 80% is controlled by three PBMs.

The senator was told by an aide that they were talking about UnitedHealth Group Inc. (NYSE:) Optum, CVS Health Corp. (NYSE::) CVS Caremark. Cigna Corp Express Scripts (NASDAQ) (NYSE:). PBMs negotiate price with manufacturers and maintain a database of drugs included in health insurance plans.

Cantwell’s Office cited a report from the Congressional Budget Office that found eliminating spread pricing could save Medicaid (federal insurance for the poor) approximately $900 million over ten years.