The INSULIN Act of 2026 contains two provisions aimed at understanding and improving insulin access and affordability. Section 4 requires the Government Accountability Office to study uninsured Americans who use insulin within two years, examining where they live, why they lack insurance, their demographic characteristics, and income levels by gathering data from advocacy groups, doctors, and healthcare providers. Section 6 establishes a new "competitive biosimilar" designation that allows the FDA to fast-track review of biosimilar insulin applications when the market has fewer than three competing alternatives and at least three years have passed since all patent protections expired, with the FDA required to decide within 60 days whether to grant this expedited status. Together, these provisions seek to address insulin access gaps and encourage more insulin options in the marketplace.