WASHINGTON — A prescription drug compromise that would lower costs for Medicare recipients and save billions for Medicare and Medicaid cleared a key hurdle in the Senate on Thursday, but Republican resistance signaled trouble as the legislation faces floor consideration.

The Finance Committee voted 19-9 to advance the bill, but it passed because of unanimous support from the panel’s Democratic minority, while a majority of Republicans opposed it.

The bill would for the first time limit out-of-pocket medication costs faced by seniors to $3,100, starting in 2022. Currently there is no cap, and some Medicare recipients face copays rivaling a mortgage payment.

It would also require drug companies to pay rebates to Medicare if they raise prices faster than inflation. Those inflation rebates are a problem for some Republican senators, who see them as a pathway to government price controls.

The legislation reflects a compromise between Finance Chairman Chuck Grassley, R-Iowa, and the panel’s senior Democrat, Ron Wyden of Oregon. The powerful pharmaceutical lobby is opposed, and executives met Wednesday night with President Donald Trump to air their concerns. There were no signs Thursday that Trump’s position had shifted. “The White House applauds the Senate Finance Committee for passing this important piece of legislation,” said spokesman Judd Deere.

During its debate, the committee defeated an amendment by Sen. Pat Toomey, R-Pa., that would have stripped the inflation rebates from the bill.