An empty bottle of Insulin lispro by French multinational pharmaceutical company Sanofi is photographed as an arranged illustration in London on February 21, 2019.

Sanofi said Wednesday it will sell monthly supplies of insulin for a fixed price of $99 for patients paying with cash in the U.S. as the pharmaceutical giant faces intense pressure from the Trump administration and Congress to lower the cost of its nearly 100-year-old, life-saving medication.

The move is a pre-emptive one as the French drugmaker is set to testify before the House Energy and Commerce Committee on the rising prices of insulin later in the day. Executives from insulin producers Eli Lilly and Novo Nordisk are also set to testify in the hearing titled, "Priced out of a lifesaving drug: Getting answers on the rising cost of insulin."

Sanofi said people can buy up to 10 products — whether vials, pens or a mix of both — for $99. This includes all of Sanofi's insulin brands. Sanofi first introduced the program ""Insulins Valyou Savings" last year, though it was more expensive. One 10 milliliter vial of insulin cost $99 and a box of pens cost $149, meaning that people who needed multiple items could end up paying hundreds of dollars. Patients can participate in the program regardless of their income level.

The drugmaker says this isn't an attempt to woo lawmakers. The company said it decided to expand the program after hearing stories of people rationing their insulin because they couldn't afford it; some even died as a result.

"It is unacceptable to Sanofi that some people living with diabetes are struggling to pay for their insulin, so we have moved to act creatively and aggressively to help address affordability and access needs," said Michelle Carnahan, the head of North America primary care at Sanofi.

The Centers for Disease Control and Prevention estimates more than 30 million Americans have diabetes. The annual cost of insulin for people with Type 1 diabetes in the U.S. nearly doubled from 2012 to 2016 to $5,700 from $2,900.

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Drugmakers argue these prices are simply the price that's advertised, not what consumers actually pay. But people without insurance may be forced to pay upfront, sometimes leaving them with a mountain of debt.

Drug companies blame pharmacy benefit managers, sometimes called "middlemen," for the sticker shock some patients see. They argue that PBMs should pass the rebates negotiated with manufactures along to patients. PBMs deny rebates are to blame for high drug prices. CVS Health and other pharmacy middlemen told a Senate committee on Tuesday that drugmakers, in their pursuit of profits, are to blame for high drug prices.

The Trump administration earlier this year proposed a rule to end the industry-wide system of rebates, a change that Sanofi and other pharmaceutical companies welcomed.

Sanofi isn't the first company to announce reducing prices. In March, Eli Lilly announced plans to sell a half-price version of its blockbuster insulin medication Humalog, and also disclosed for the first time what it charges wholesalers versus what many patients typically pay.