WASHINGTON — In his State of the Union address in January and again in New Hampshire in March, President Trump made a bold promise: “You’ll be seeing drug prices falling very substantially in the not-too-distant future,” he said, “and it’s going to be beautiful.”

Not if the pharmaceutical companies can stop it.

Big Pharma is pouring money into a lobbying campaign to thwart any serious efforts to rein in prescription drug prices ahead of a presidential speech this month where Mr. Trump plans to lay out his drug pricing proposals.

“There is apprehension across the industry,” said Bruce Artim, who retired recently after 11 years as the director of federal affairs at Eli Lilly and Company. “Pharma folks are nervous.”

Drugmakers spent $171.5 million lobbying the federal government last year — more than insurance, electronics, oil and gas or any other industry, according to data compiled by the Center for Responsive Politics, an independent group that tracks money in politics.