President Trump criticized drug companies in a Twitter post. (Jim Watson/AFP/Getty Images)

President Trump on Monday said Pfizer and other pharmaceutical companies “should be ashamed” of themselves for raising drug prices and vowed a government response, just two months after saying he had put forward a plan to “derail the gravy train.”

Trump’s comments, which came in a Twitter post, appeared to be in response to a Financial Times report that showed that Pfizer had raised prices on roughly 100 drugs. Trump had promised to lower drug prices as part of his 2016 campaign, and he threatened to use the government’s clout to negotiate lower prices. But he opted against taking this step earlier this year, opting instead to release multiple ideas in a 44-page document that his advisers argued could eventually lower prices if implemented.

No concrete steps were taken, but Trump predicted that the industry would respond anyway and that there would be “voluntary, massive drops in prices” within two weeks. Such a reduction never took place, and companies instead decided to raise prices on a number of drugs. This prompted Trump’s response.

Wells Fargo Securities issued a report this month that found that Pfizer raised prices on 41 drug products on July 1 and lowered prices on five products. Across the industry, Wells Fargo found, companies rose drug prices on 63 products and lowered prices on 64 products in June.

This was the second time in recent weeks that Trump has vowed retaliation against a large, publicly traded company that he accused of doing something that ran counter to his agenda. He also attacked Harley-Davidson after it announced that it would move some operations outside the United States, threatening to hit the firm with severe taxes.

Dean Mastrojohn, a Pfizer spokesman, said the company’s “price list remains unchanged for the majority of our medicines.” He said the company was “modifying prices” for roughly 10 percent of its 400 medicines and vaccines, and that “list prices do not reflect what most patients or insurance companies pay.”

Much of Trump’s economic agenda has called for sweeping tax cuts and deregulation that he says will help businesses in ways that create benefits for consumers. But there are signs that a number of companies that enjoyed the benefits of these policies without fully passing along all the savings to their customers and employees. For example, a number of Democrats in Congress have complained that large companies have used big savings from last year’s tax cuts to buy back stock in a way that benefits shareholders, rather than use the money to boost wages or cut prices.

Trump appears to have long harbored a distrust of the pharmaceutical industry, but so far he has done little to crack down on these companies since taking office. Nine days before he was sworn in last year, he said he wanted to pursue the creation of a bidding process for drugs in a way to push prices down.

“Pharma has a lot of lobbies, a lot of lobbyists and a lot of power. And there’s very little bidding on drugs,” Trump said during an event at Trump Tower in New York. “We’re the largest buyer of drugs in the world, and yet we don’t bid properly.”

At the time, many U.S. companies were worried about what might happen if Trump decided to lead a charge against their industry, and stocks for pharmaceutical companies fell that day. But on Monday, even after Trump singled out Pfizer by name and vowed a response, the company’s investors appeared to mostly shrug it off.