WASHINGTON — U.S. Sen. Tim Kaine joined Sen. Patty Murray to send letters to executives at three insulin manufactures in the U.S., demanding information about its rising prices.

The letter was sent to Eli Lilly, Novo Nordisk, and Sanofi.

A new study claimed that the price of insulin for a person with Type 1 Diabetes nearly doubled in the span of five years. It found the annual cost for the typical patient went from $2,864 in 2012 to $5,705 in 2016. That's an increase of 99.2 percent. 

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The Senators wrote:

“According to the World Health Organization, insulin is an essential medicine, meaning that access to this drug at a price that individuals and communities can afford is a basic requirement of a functioning health care system. Unfortunately, rapidly increasing insulin prices mean that for many patients, access to this essential medicine is threatened. Patients have had to resort to desperate measures when confronted with increased insulin prices or high cost-sharing for their prescriptions. Some patients have turned to GoFundMe pages to request help paying for insulin, and one in four diabetic patients report rationing the medication because of the cost, with potentially devastating consequences. It is clear these steep price increases are resulting in patients lacking access to the life-saving medications they need."

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The letter was also signed by Senators Bernie Sanders (D-VT), Bob Casey (D-PA), Tammy Baldwin (D-WI), Chris Murphy (D-CT), Elizabeth Warren (D-MA), Maggie Hassan (D-NH), Tina Smith (D-MN), Doug Jones (D-AL), and Jacky Rosen (D-NV).

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