A bill to cap the cost of insulin and authorize the state to find out why the drug costs so much is headed to Colorado Gov. Jared Polis to become law.

The House accepted changes to House Bill 1216 Tuesday and re-passed the bill on a 50-15 vote.

The Senate amended and passed the legislation 22-12 on Saturday.

With the governor’s signature, the cost of a month’s supply of insulin for an individual can cost that person no more than $100.

The bill also instructs the state Department of Law to investigate insulin pricing then report those findings to the governor, the commissioner of insurance, and the judiciary committees of the state House and Senate.

House Democrats said about 420,000 Coloradans have the illness, and 20,000 new diabetics are diagnosed each year.

Without a generic competitor, the prices of the four most popular types of insulin have each tripled over the last decade, with the average price at about $450 per month, as prices continue to climb.

Members of Congress, including Rep. Diana DeGette, D-Denver, are pressing drug companies to explain the hikes and lower the prices, with varying responses.