Colorado has capped the price of co-pays for insulin, making it the first state to enact a law that combats the soaring costs for the medication that have doubled in the last seven years.

Democratic Gov. Jared Polis signed the bill into law earlier this week restricting the price for insured patients to co-pays of $100 a month, according to the Denver Post. The law goes into effect in January.

Insulin helps regulate blood sugar for diabetics and is often essential for survival. The Center for Disease Control estimates that more than 100 million Americans suffer from diabetes or pre-diabetes.

The skyrocketing cost of insulin has prompted lawmakers, including Congress, to call for price caps and pharmaceutical companies to find ways to drop the cost for patients.

Between 2012 and 2016, prices for insulin nearly doubled, according to a March report from the U.S. House of Representatives. Insulin can cost between $600 and $1,000 a month on average.

“Today, we will declare that the days of insulin price gouging are over in Colorado,” Polis told CBS Denver.

Colorado's new law also requires state Attorney General Phil Weiser to investigate why insulin prices skyrocketed in recent years and issue a report to the legislature.

The high price of insulin has led some diabetics to forgo the medication or ration doses, putting their lives at risk.

NPR reported last year that an uninsured Minnesota man died of diabetes complications because he couldn't afford $1,300 monthly cost of insulin.

Express Scripts, one of the largest pharmacy benefit management companies in the nation, vowed to cap insulin at $25 a month for patients, according to NPR.

Express Scripts covers millions of people who take insulin. Earlier this year, Ely Lilly said it would offer a generic version of the Humalog brand insulin at half the price.