(Bloomberg) -- President-elect Donald Trump promised to drive down the cost ofmedicines, defying investors who saw a boon in his electionlast month and injecting himself again into a contentious economicdebate.

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“I’m going to bring down drug prices,” Trump said,according to a transcript of an interview posted on Time magazine’swebsite as it named him its Man of the Year. “I don’t like what’shappened with drug prices.”

Over the past 18 months, companies including EpiPen allergy shot maker Mylan NV and ValeantPharmaceuticals International Inc. have borne the brunt of publicoutrage over costs. Last week, the chief executives ofRegeneron Pharmaceuticals Inc. and Pfizer Inc. sparred over thereasons their industry’s reputation has suffered, including therole that prices have played.

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Trump has joined that critical chorus.

His comments published Wednesday were his latest swipe atAmerican industries he views as out of line.

He has singled out Carrier Corp. and Ford Motor Co. in effortsto keep jobs in the U.S., and on Tuesday called out Boeing Co. forthe cost of replacing the Air Force One presidential aircraft.

Investors believed the election of Trump, a 70-year-oldRepublican, would be a blessing for free-market health care.

His Nov. 8 victory was greeted with a surge in pharmaceuticalstocks, but the Nasdaq Biotechnology Index was down as much as4.6 percent Wednesday in New York, the biggest intraday loss sinceJune 24 and the lowest since the election.

Holly Campbell, a spokeswoman for PhRMA, the drug industry’sWashington-based trade group, said that the focus should be onreducing out-of-pocket costs for patients and increasing access,but resolution should be brought by the industry.

"Government mandates and interventions are not the solution forpatients," she said in a statement. "We look forward to workingwith the administration next year on solutions that will enhancethe competitive private market and ensure we continue to deliverinnovative treatments and cures to patients."

Drug-company executives and industry observers have already saidthat Trump may scrutinize their prices as a populist issue.

Allergan Plc Chief Executive Officer Brent Saunders said at aconference last week that Trump might be more “vicious” thandefeated Democratic presidential candidate Hillary Clinton.

Saunders, who has argued that industry should police itself,worried that drug companies had a “false sense of relief.”

“If our industry can self-regulate on pricing, we can all focuson investing in innovative medicines and cures and move the pricingdiscussion to the back burner. I think everyone, especially thepatient, is better off if that happens,” he said in a statementWednesday.

Profitable pills

The U.S. doesn’t directly regulate medicine prices, unlike muchof the rest of the globe. Setting the cost is a murky process: Listprices are set by drugmakers, rebates are privately negotiated withintermediaries and the out-of-pocket cost customers pay at thepharmacy varies is based on whether or not they have insurance, andhow good it is.

Trump, whose transition team didn’t immediately return ane-mail seeking comment, didn’t make drug costs a major focus duringthe campaign. He has supported allowing consumers to re-importdrugs from abroad, and mentioned having the Medicare health programfor the elderly negotiate prices directly with pharmaceuticalmanufacturers.

Both ideas have long been opposed by the industry and manyRepublicans -- including Representative Tom Price, the Georgiacongressman whom he has tapped to lead the Department of Health andHuman Services.

Yet drug costs could also be an area of common ground inWashington. An October pre-election survey by the Kaiser FamilyFoundation found that the burden was the top health-care issue forthe next president. Senator John McCain, an Arizona Republican, hasproposed requiring drugmakers to report any price increase of morethan 10 percent. Representative Elijah Cummings, a Democrat fromMaryland, has led his party’s charge against high drug prices.

Trump said this year that renegotiating Medicare prices wouldsave $300 billion a year as the government is the biggest purchaserof prescription drugs. That hypothetical figure, however,would represent the bulk of the $324.6 billion that the U.S. spenton prescription drugs last year, according to the Centers forMedicare and Medicaid Services.

Also, negotiating prices for high-cost drugs alone wouldn’tlimit costs, according to an analysis from the Congressional BudgetOffice. The government would also need the ability to refuse tocover certain drugs.

Quintiles IMS Holdings Inc. estimates the U.S. will spend $461.7billion on pharmaceuticals this year, and figures that’ll increaseat an annual rate of 6 percent to 9 percent through 2021.

Holding back

Drug CEOs say they don’t gouge consumers. Merck & Co. CEOKen Frazier said in an interview last week that his company hasbeen restrained in raising the costs of its medicines. Saunders hasalready sought to distinguish his company from its peers with apricing pledge that limits increases. Lars Rebien Sorensenof Novo Nordisk A/S said recently his company will capincreases.

Sorensen, whose Swiss company is the world’s largest insulinmaker, said innovation comes at a “price and a premium.”

“I’d be worried if policies implemented under the newadministration lose sight of this fact in an attempt to restructurethe U.S. health system,” he said. “Then you could kill the goosethat laid the golden eggs in the process, without really knowing ituntil it’s dead.”

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