WASHINGTON (Reuters) - - The U.S. House of Representatives on Thursday approved legislation aimed at driving down the prices that seniors pay for prescription drugs, but the bill’s future is clouded by President Donald Trump’s threat of a veto and lack of support in the Senate.

The Democrat-led chamber voted 230 to 192, largely along party lines, to approve the measure that would allow the Medicare insurance program for seniors to negotiate prices for dozens of prescription drugs, including insulin. The lower drug prices would also be available to private insurance companies.

“I’ve seen grown men cry on the campaign trail because they cannot meet the prescription drug cost, whether they have a spouse that is ill or a child with a pre-existing conditions,” Speaker of the House Nancy Pelosi told reporters ahead of the vote. “This will make all the difference in the world.”

The bill would cap prices for the country’s most expensive drugs using an international index and impose hefty fines for manufacturers that do not negotiate.

The pricing system would save the government $456 billion over 10 years, according to estimates from the non-partisan Congressional Budget Office, much of which would go toward extending Medicare coverage for vision, hearing and dental care.

The bill also would prevent price-gouging on new drugs for those with private health insurance.

The Republican White House, though, said on Tuesday Trump would veto the bill should it pass the Senate because it “would likely undermine access to lifesaving medicines,” risked violating the U.S. Constitution, and reduced “the incentive to bring innovative therapeutics to market.”

But the Republican-led Senate is not expected to take up the bill, given that it is considering its own bipartisan drug-pricing legislation.

Democrats promised to curb prescription drug prices during last year’s congressional election campaign, when they won the majority in the House of Representatives. Trump has also promised to lower prices but has been struggling to deliver on that before the November 2020 election.

Many of Trump’s fellow Republicans are not keen on letting the government negotiate over prices, saying it amounts to price fixing. Elements of Pelosi’s plan are also opposed by the pharmaceutical industry.

Meanwhile, the progressive, liberal wing of Pelosi’s party had criticized the initial version of the bill for not going far enough. But earlier this week Democrats agreed to increase the minimum number of drugs to be negotiated each year to 50 from 35.