FDA approved an Alzheimer’s treatment, but 1 million Americans can’t get it

Seventy‑nine percent of voters — including 78 percent of independents — support expanded access to Alzheimer’s detection and treatment, according to a survey released in May. Yet eighty‑nine percent say Medicare and private‑insurer restrictions block patients from receiving the drugs that physicians want to slow the disease. About one million Americans qualify for FDA‑approved therapies that can slow Alzheimer’s progression, but fewer than 15,000 have actually received them. The FDA approved lecanemab in 2023 and donanemab in 2024. These agents are the first treatments that alter the disease course by clearing toxic proteins that accumulate in the brain, slowing progression by roughly 30 percent and allowing patients to remain independent longer. Two obstacles stem from a Medicare coverage rule written in April 2022. First, the rule requires doctors who wish to prescribe the drugs to enroll in a national data registry and submit patient information to a federal portal twice over two years — a bureaucratic hurdle most community physicians have not cleared. Consequently, access is limited to a handful of large academic medical centers. Second, the rule was crafted when the only accepted methods for confirming Alzheimer’s were an invasive spinal tap or a PET scan, a specialized imaging study not widely available across the country. Although cheaper, less invasive blood‑based biomarker tests now exist, the regulation has not been updated to reflect them. The 2022 rule no longer matches current science. In 2024 the leading diagnostic criteria were formally revised to incorporate blood‑based biomarker tests as stand‑alone tools for diagnosing Alzheimer’s disease. In May 2025 the FDA cleared the first blood test for Alzheimer’s diagnosis — a simple draw that is far less invasive and far less costly than a spinal tap or imaging. In July 2025 the Alzheimer’s Association issued its initial practice guideline on the use of these tests. In October 2025 the FDA cleared a second blood test designed specifically for primary‑care settings. Because the Medicare rule still mandates the outdated methods, a blood test capable of identifying Alzheimer’s in virtually any setting cannot be used to unlock coverage for treatment. Physicians who order the test, follow contemporary guidelines, and attempt to prescribe an FDA‑approved therapy will not be reimbursed. No new legislation is required to fix the problem. The Department of Health and Human Services can direct the Center for Medicare and Medicaid Services to revise the coverage rule; the entire process would take about 90 days, given that the scientific foundation — updated criteria, FDA‑approved blood tests, and professional guidelines — is already in place. A bipartisan legislative effort, the Alzheimer’s Screening and Prevention Act, would allow Medicare to cover blood‑based tests for early detection and help close the diagnostic delay. The bill enjoys strong support in both chambers of Congress, but its passage should not delay the immediate administrative fix to the coverage gap. The FDA has fulfilled its role, as has the medical community. What remains is a Medicare rule written for a circumstances that no longer exists. The evidence and the authority to act are in hand; one million Americans are waiting.