The bipartisan request to the Federal Trade Commission by Senate Judiciary Chairman Charles Grassley and Ranking Member Patrick Leahy comes just a few weeks before the committee is slated to convene a hearing to scrutinize a pending $465 million settlement that Mylan has said will resolve claims it underpaid rebates to state and federal Medicaid programs.

“Due to the dramatic increase of the price of drugs across the board, the FTC should be vigilant in its scrutiny of this market,” the lawmakers wrote.

In a statement emailed to Reuters, a Mylan spokeswoman defended the company’s ‘EpiPen4Schools’ program, saying it has no purchase requirement for schools to participate and that it offers schools four free EpiPens per calendar year also without purchase restrictions.

Previously, schools that wished to purchase additional EpiPens could do so in some cases with a discount and a “limited purchase restriction,” but no such restriction remains in place today, she added.

A spokeswoman for the FTC declined to comment on the letter.

Mylan has come under fire in recent months by lawmakers for hiking the price of EpiPen to more than $600 for a package of two in less than a decade.

Last month, it said it had reached a $465 million settlement with the Justice Department to resolve claims it misclassified the EpiPen as a generic drug instead of a branded one, thereby underpaying rebates for Medicaid.

The Justice Department has yet to publicly acknowledge the settlement, which will be discussed at the Nov. 30 hearing.

Also on Monday, three members of the Senate Judiciary Committee asked the company when it plans to reimburse the Department of Defense for any overcharging on EpiPen.

Separately, the West Virginia Attorney General’s Office is investigating Mylan over antitrust concerns and the rebates, while the New York Attorney General is scrutinizing Mylan’s contracts with schools for the EpiPen for possible violations of state antitrust laws.