WASHINGTON – Newly empowered House Democrats launched Monday an investigation of the rising prices of popular drugs to treat diabetes, arthritis, cholesterol and other ailments, a prelude to public hearings starting later this month that could lead to legislation to cut medicine costs.

The House Committee on Oversight and Reform sent letters to 12 drug companies to try to determine why prices have risen “so dramatically,” how drug companies are using their profits, and what can be done to reduce costs for patients.

“There hasn’t been a time when drug companies have gotten this much pushback from both side of the political spectrum on their pricing practices,” said Larry Levitt, senior vice president for health reform at the nonpartisan Kaiser Family Foundation.

Reducing the cost of medicine is one of the few goals that both Democrats and President Donald Trump have named a top priority.

The administration has been acting on its own but is limited in what it can do and how quickly it can do it without legislation.

Republican Sen. Chuck Grassley, the new chairman of the Senate Finance Committee, has said he will try to find solutions.

“It’s one of the top concerns I hear from Iowans,” Grassley recently wrote.

But the initiative is stronger on the Democratic side, said Rachel Sachs, an expert on drug pricing legislation at Washington University in St. Louis.

“The Democrats have advanced an affirmative agenda on what to do on drug pricing,” said Sachs, an associate professor of law. “Different Democrats have different ideas about how to advance each of those goals, but they are all on board with those goals. Republicans have not really advanced an agenda in the same way.”

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Rep. Elijah Cummings, the Maryland Democrat who heads the House oversight committee, joined other Democrats last week in outlining a strategy that includes tying drug prices to their cost in other countries – a proposal similar to, but more far reaching, than a Trump administration plan. Democrats are also renewing past efforts to enable medicines to be imported from other countries and to allow the government to negotiate for lower prices for Medicare drugs.

About one in four people taking prescription drugs have trouble paying for them, according to the Kaiser Family Foundation's Health Tracking Poll. The poll has also found that about half the public thinks passing legislation to bring down the cost of medicine should be the government’s top priority.

The hearings on the horizon could galvanize the public further.

In the past, lawmakers have called to the stand the maker of the EpiPen and the head of a company that raised the price of an old drug used to treat AIDS patients by 5,000 percent.

Cummings promised Monday to conduct “one of the most wide-ranging investigations in decades” into the drug industry’s pricing practices.

“There’s been a lot of focus on how the new Democratic majority in the House could investigate the Trump administration,” Levitt said, “but this is a good reminder that they can investigate industries, too.”

Investigators are focusing on drugs that are among the costliest to Medicare, among the costliest per beneficiary, or had the largest price increases over a five-year period.

Of the 19 drugs the committee is asking about, the most – five – are used to treat diabetes.

That includes Humalog KwikPen U-100, a lightweight pen filled with a rapid-acting form of insulin made by Eli Lilly and Co. where Health and Human Services Secretary Alex Azar was a top executive.

Prices for diabetic treatments have continued to rise even though the products are rooted in old technology, Sachs said.

Legislation proposed by Sen. Elizabeth Warren, D-Mass., and others would require the government to make generic versions of medicines, including insulin.

Lilly and other insulin makers have said that even when list prices for their medicines go up, the amount they’re being paid can go down.

That’s because insurance companies and pharmacy benefit managers are demanding rebates, although the patient may not see the discount.

Asked about Cummings’ request for information, a Lilly spokesman said the company appreciates Congress’ interest in the topic. But drugmakers are only one piece of the puzzle.

“A comprehensive policy solution for people with chronic diseases requires commitment from everyone in the health care system,” said spokesman Gregory Kueterman. "To that end, we look forward answering questions from the committee."