Responding to tough talk by presidential candidates about price gouging by drug companies, pharmaceutical executives have told investors that they are working actively to influence the political debate. And in a move that reveals how much leeway drug firms actually have over pricing decisions, some are even saying that they have minimized price hikes in recent months to avoid attracting attention.

Democratic contenders Bernie Sanders and Hillary Clinton have both called for the government to do much more to bring down the price of medications. And last week, Republican candidate Donald Trump came out in support of allowing Medicare to negotiate for cheaper drug prices, a move that places him even to the left of some leaders in the Democratic Party.

On Thursday, former pharmaceutical executive Martin Shkreli is scheduled to join other executives in testifying before a congressional panel about why they hiked prices on lifesaving drugs by as much as 5,000 percent.

The political environment has Wall Street worried. “We heard Bernie and Hillary last night go after drug pricing again and I think that’s also something we are going to hear from the Republicans,” warned Jami Rubin, the Goldman Sachs health care group analyst, on an earnings conference call last week for Johnson & Johnson.

Eli Lilly executive Jan Lundberg assured investors on his company’s most recent earnings call that to combat the rhetoric around drug prices, the industry maintains “an active dialogue with each of the candidates” and will “work across party lines” to influence policy.

Merck chief executive Ken Frazier, speaking at the J.P. Morgan Health Care Conference in San Francisco last month, pledged to do more as chairman of the Pharmaceutical Research and Manufacturers of America (PhRMA), the industry’s lobbying group. “With respect to the political dynamic,” Frazier said, “I think the most important thing, and I try to do this in my role as head of PhRMA, is I think the industry needs to communicate better with the outside world.”

At the same conference, Biogen chief executive George Scangos, who also serves as co-chairman of PhRMA, said his firm increased prices on three drugs recently, but at a “somewhat lower number” to avoid placing “a target on our foreheads.” He added that “it’s still possible to take price increases” but that he thinks “it’s wise to be a little prudent.”