WASHINGTON — Rep. Tom Price told the Senate Health Committee on Wednesday that he would protect vulnerable Americans if he is confirmed as President-elect Donald Trump's Health and Human Services secretary.

But the six-term congressman from Georgia did not detail how he would fulfill that pledge, including how he would replace the Affordable Care Act and how he would preserve coverage for the more than 100-million Americans who rely on Medicare, Medicaid and the health care law, commonly called Obamacare. Price has worked for years to roll back all three.

During a testy four-hour hearing on Capitol Hill — which also featured several heated exchanges about his ethics — Price also repeatedly dodged questions from Democrats seeking assurance that he would preserve basic protections.

Among other things, Obamacare bans lifetime limits on coverage and mandates that plans allow parents to keep their children on their insurance until they are 26.

“My constituents are coming up to me with tears in their eyes wondering what the future holds for their health care,” Sen. Patty Murray, D-Wash., the senior Democrat on the heath committee, told Price.

Price, whom Trump has said is helping develop the new administration's proposed Obamacare replacement, repeatedly assured lawmakers that Americans would be able to get the health insurance they want.

“It's absolutely imperative that individuals that have health coverage be able to keep health coverage and move hopefully to greater choices and opportunities for them,” Price told the committee.

At one point, he even said he hopes the Obamacare replacement will cover more people than the current law.

Obamacare has helped more than 20 million previously uninsured Americans gain coverage in the last three years. Repealing it would immediately result in 18 million people losing coverage, according to a new analysis from the nonpartisan Congressional Budget Office.

Price has been among the law's most ardent critics and has pushed budget plans that would cut trillions of dollars from Medicare and Medicaid.

Like Trump, Price offered no indication how it will be possible to cover more people, preserve consumer protections and make health insurance cheaper all at the same time.

However, Price refused to say Wednesday whether he would back efforts to expand the government's authority to negotiate lower prices from drug makers, despite Trump's recent calls to do so.

Trump once made the cost of pharmaceuticals a central part of his campaign health care pitch. And at his first news conference last week, the president-elect said drug makers were “getting away with murder.”

“We're the largest buyer of drugs in the world, and yet we don't bid properly,” Trump said.

Republicans have long opposed allowing Medicare to use its market power to negotiate lower prices for seniors.

And the pharmaceutical industry, which also opposes price negotiation, has protected its interests by lavishing political contributions on members of Congress. Price himself has received tens of thousands of dollars from drug makers and has also invested heavily in industry stocks, records show.

Those ties also featured prominently in Wednesday's hearing, as Democrats pounded Price for repeatedly trading stocks in companies that were affected by his work in Congress.

As the hearing grew increasingly tense, several lawmakers reiterated calls for an independent investigation of Price for pushing legislation that increased the value of several stocks after he bought them.

“This whole administration is starting to look like a bit of a get-rich-quick scheme,” Sen. Chris Murphy, D-Conn., told Price, linking his stock trading to Trump's refusal to divest his business holdings.

Last year, Price bought up to $15,000 worth of stock in medical device maker Zimmer Biomet just a week before introducing legislation that would have delayed a new regulation that threatened the company's bottom line, according to reporting by CNN.

noam.levey@latimes.com