My son needs insulin to survive. Plans to lower drug costs are welcome, but not enough.

Novo Nordisk and Sanofi announced last week that they will lower prices on some of their insulin products by up to 78% effective January 2024. That follows Eli Lilly’s recent announcement that it will lower some of its insulin prices by 70% later this year.

My son – who was diagnosed with Type 1 diabetes, an autoimmune disease that destroys the body’s ability to make insulin – obtains his insulin from Novo Nordisk, and so this news brings significant financial relief for my family.

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While decisions like this are welcomed by families like mine, without a federal bill that caps insulin prices for everyone, there is no guarantee that companies will continue to choose people over profits.

Insulin prices rose 600% over 2 decades

More than 8 million people in the United States rely on insulin to survive, including individuals with Type 2 diabetes whose bodies are unable to use insulin properly. While the newly passed Inflation Reduction Act caps monthly insulin costs for Medicare patients at $35 a month, it does not cover the broader patient population under private health insurance.

Insulin prices in the United States rose astronomically, more than 600%, in the past 20 years, far outpacing the rate of inflation and costing up to 10 times more than the average price in other countries. The price of insulin can cost about $300 a vial, and individuals with Type 1 diabetes can use three to six vials a month.

President Joe Biden has called for action to lower insulin prices and asked pharmaceutical companies such as Eli Lilly (based in the United States) and Novo Nordisk (based in Denmark) to voluntarily lower prices on their own. On Thursday, Sanofi, based in France, joined the others in deciding to reduce its prices.

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However, even with private insurance, high-deductible plans require patients to pay for 100% of the costs until their deductible is met. It creates an economic hardship for lower- and middle-class insulin users, let alone those without insurance.

Without insulin, diabetics can develop eye disease, kidney disease and diabetic ketoacidosis, which if left untreated will result in death. Some individuals have resorted to insulin rationing in an effort to manage the exorbitant costs and lost their lives as a result.

Diabetes will still lead to high medical costs

Although purchasing insulin from Eli Lilly, Novo Nordisk or Sanofi in the future might seem an easy solution to lowering patients' costs, it's not that simple. Insurance companies and pharmacy benefit managers dictate which products are covered under particular health plans. And the price of insulin is only a fraction of the cost associated with managing diabetes.

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Individuals with Type 1 diabetes also require additional monthly medical supplies if they use an insulin pump. The overall cost for individuals, even with private health insurance, is on average almost $10,000 a year.

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People with diabetes should not have to choose between paying for their insulin and other necessities. Without a federal bill, there is no guarantee companies won't raise prices in the future, particularly if lawmakers and public opinion fail to keep the pressure up.

Legally capping the price of insulin would bring a welcome financial relief to millions of Americans and save lives.

Kimberly M. Baker is an associate professor of biology at the University of Indianapolis and a molecular geneticist by training. She is a Public Voices Fellow with The OpEd Project. 

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This article originally appeared on USA TODAY: Insulin price drop is good news. But people with diabetes need more.