A bipartisan group of U.S. Senators is urging the Federal Trade Commission to investigate possible illegal collusion by saline solution manufacturers. The U.S. has had a shortage of saline solution since 2013, and the Senators noted that the three companies that provide all of the saline solution in the U.S. — Baxter International, Hospira, and B.Braun—have failed to end the shortage, but have raised prices by 200 to 300%.

“Price increases often help clear shortages, but in this case the shortage is still ongoing after nearly two years, raising questions about the incentives of the saline suppliers to solve this problem and about possible coordination among them.”

Debora Spak, a spokeswoman for Baxter, told Modern Healthcare that the average selling price of Baxter’s commonly prescribed one-liter sterile saline solution in the U.S. has increased annually at a modest level, in the single to low double digits – nothing like the amounts cited by the senators.

The Senators wrote a letter to FTC Chairwoman Edith Ramirez, and urged and requested an investigation. The Senators include Richard Blumenthal (D-Conn.), Mike Lee (R-Utah), Amy Klobuchar (D-Minn.) and Orrin G. Hatch (R-Utah). Senators Lee and Klobuchar are the Chairman and Ranking Member, respectively, of the Judiciary Subcommittee on Antitrust, Competition Policy and Consumer Rights, and Senator Hatch is the former Chairman of the full Judiciary Committee.

“The saline suppliers’ ability to extract several-hundred-percent price increases and to lock their customers into long term contracts is likely reducing their incentive to alleviate this troubling shortage, which, in turn, further exacerbates the shortage and results in consumer harm,” the Senators wrote.