Add businessman Steve Forbes to the long list of people criticizing House Democratic proposals for lowering drug prices — a prominent part of the party's agenda that was eventually altered amid intraparty backlash.

"On way to vote, @SpeakerPelosi makes her #socialist prescription drug bill even worse to appease her caucus progressives," Forbes tweeted, referring to House Speaker Nancy Pelosi, D-Calif.

"This bill would keep lifesaving drugs from the market, destroy an American industry & ignore real reasons for high health care costs."

It came amid news that Pelosi altered her original proposal in response to progressive members' concerns.

PELOSI CEDES TO PROGRESSIVE CAUCUS DEMANDS IN DRUG PRICING BILL AFTER AOC, OTHERS THREATENED TO DELAY VOTE

Forbes' criticism echoes the White House's, which argues that Pelosi's price controls would block 100 drugs from reaching the market. Pelosi's plan would presumably have a wide-reaching impact in that it would make negotiated drug prices available to everyone — not just those with Medicare.

Democrats' legislation would focus on allowing Medicare to negotiate lower prices for the most expensive drugs. The Congressional Budget Office estimated that Pelosi's plan would save the agency $345 billion over a decade.

PELOSI, PROGRESSIVE CAUCUS CLASH OVER DRUG PRICING LEGISLATION

That could change with the bill's latest iteration, which would increase the number of drugs that can be negotiated under the bill, extending protections against drug price hikes.

While the bill likely won't gain traction in the GOP-led Senate, it could serve as an opportunity for Democrats to advance a drug pricing plan as the administration advocated its own.

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The alterations were brokered by the Congressional Progressive Caucus and will likely feed Republicans' narrative that Pelosi's party is increasingly run by its more progressive elements.

Fox News' Brie Stimson contributed to this report.