(CNN) The skyrocketing prices of insulin are a nationwide issue and Colorado has become the first state to pass legislation that tackles the problem.

Colorado Gov. Jared Polis signed a bill into law Wednesday that places a $100 per month cap on insulin co-pays, regardless of how much insulin a patient uses. Insurance companies will pay anything more than the $100 co-pay, according to the new law.

The law also enlists the Colorado attorney general to investigate the rising prices of insulin in the state and to make recommendations back to the legislature.

"Today we will finally declare that the days of insulin price gouging are over in Colorado," Gov. Polis said before signing the bill on Wednesday.

The bill was sponsored by Democratic state Rep. Dylan Roberts, who lost his brother to Type 1 diabetes in August 2016.

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