The company said it would cap the monthly out-of-pocket cost of the diabetes products at $35.

The drugmaker Eli Lilly and Company said on Wednesday that it would significantly reduce the prices of several of its lifesaving insulin products that are used by diabetes patients and whose prices Lilly has repeatedly increased in the past.

Lilly also said it would cap at $35 a month what patients pay out of their own pockets for the company’s insulin.

The move marks at least a partial retreat for a company that has been a primary contributor to soaring prices for an injection that millions of Americans rely on to keep their blood sugar levels in check. It comes at a time of mounting political pressure on drug companies to rein in what lawmakers and other critics view as the industry’s pattern of abusive profiteering.

Over nearly three decades, for example, Lilly has raised the price on its most widely used insulin product, Humalog, by more than 1,000 percent.

The high costs for insulin made by Lilly and other drug companies — out-of-pocket payments for people on certain high-deductible insurance plans can exceed $1,000 a month, though many patients pay far less — have led many patients to ration their medicines or, in some cases, to stop taking them altogether.

In his State of the Union address last month, President Biden blasted drug companies for increasing the prices for insulin. “Big Pharma has been unfairly charging people hundreds of dollars, $400 to $500 a month, making record profits,” he said.

On Wednesday, Mr. Biden hailed Lilly’s move as “a big deal, and it’s time for other manufacturers to follow.”

Lilly’s moves, however, are limited. The lower list prices, which will take effect over the course of this year, apply only to the company’s older insulin products. And a large percentage of diabetes patients who need insulin take products made by two other major drug manufacturers, Sanofi and Novo Nordisk.

Stacie Dusetzina, a professor of health policy at Vanderbilt University School of Medicine, said Lilly’s changes would be helpful for diabetes patients who are uninsured or underinsured. But she noted that insurers already pay less than the sticker price for the insulin products because of a variety of discounts and rebates.

Still, she said, “I don’t think that these prices are quite as impressive as they look when you first see them.”

“It doesn’t necessarily mean that Lilly is taking a big financial hit to do this,” she added.

Lilly’s announcement “does not mean that the situation is fixed or everything is solved,” said Elizabeth Pfiester, who has diabetes and is the executive director of T1International, a group that has been pushing for a federal ceiling on insulin list prices.

More than 30 million Americans have diabetes, and more than seven million of them rely on insulin. Without insulin, patients can die or face serious health consequences including amputation and kidney failure.

Lilly’s price cuts follow years of mounting pressure not just from officials in Washington and state capitals but also from a well-organized community of patients who have called for insulin to be more affordable.

Lilly’s move to limit out-of-pocket costs expands on a change that went in to effect at the start of this year for patients on Medicare. Under last year’s Inflation Reduction Act, Congress imposed a $35 a month ceiling on insulin co-payments for Medicare patients.

Lilly said that it planned in the last three months of this year to reduce the list price of its most commonly used insulin, Humalog, by 70 percent.

A vial of Humalog — patients often go through several vials per month — has a list price of $275; Lilly plans to reduce that to $66. That will still be more than triple the list price when Humalog was introduced in 1996. (Lilly said it will also sharply reduce the list price of its generic version of Humalog, as well as another of its insulin products, Humulin.)

In April, Lilly plans to introduce a similar version of rival Sanofi’s insulin product Lantus. It said that would offer it at a 78 percent discount to Lantus’s list price.

Lilly said that one of its newer versions of Humalog, a prefilled insulin pen that has a list price of $530, would not be discounted. And the company said it would not cut the price of its long-acting insulin product, Basaglar, which was first approved in 2015.

Ms. Pfiester said her group is continuing to push for a federal price cap on insulin. Lilly’s announcement, she said, “is good news for some, but we need regulation to make sure that the companies can’t change their mind again and decide to raise the price.”

Insulin costs an estimated $10 per vial to manufacture.

When Frederick Banting helped invent the drug a century ago, he refused to put his name on the first patent application because he felt it would be at odds with the Hippocratic oath he had taken as a physician. The two scientists whose names were on that patent application, James Collip and Charles Best, transferred the patent to the University of Toronto for $1, in the hopes of making it as widely available and affordable as possible.

That has not happened. In recent years, the leading insulin manufacturers, including Lilly, have replaced older products with newer, costlier versions and steadily increased their prices.