The Japanese Health Ministry is expected to approve a new Alzheimer’s drug, donanemab, following a recommendation from a ministry panel on Thursday. This approval would make donanemab the second drug available in Japan for treating the neurodegenerative disease.
Developed by the U.S. pharmaceutical company Eli Lilly, donanemab targets amyloid beta, an abnormal protein that builds up in the brains of Alzheimer’s patients. The drug is designed to slow the disease’s progression, particularly in patients with early-onset Alzheimer’s.
In preliminary trials, donanemab slowed cognitive decline by 35% compared to a placebo. The U.S. Food and Drug Administration approved the drug for production and sale in July.
Eli Lilly applied for approval in Japan last August. The health ministry’s panel approved donanemab with the condition that detailed information about patients receiving the drug would be collected. This data is needed to assess the drug’s safety and effectiveness.
In the U.S., donanemab costs $32,000 (¥4.8 million) for a year’s supply. The price in Japan has not yet been set.
Donanemab’s potential approval follows the recent approval of lecanemab, a drug developed by Japanese firm Eisai and U.S. company Biogen. Lecanemab was approved in September and became available in December.
Unlike lecanemab, which requires bi-weekly infusions, donanemab can be administered monthly. While lecanemab is used for 18 months, treatment with donanemab can end once amyloid beta levels are reduced.
The approval comes as dementia rates in Japan rise. A government report from earlier this year projects that by 2040, nearly 6 million people—about 15% of those over 65—will have dementia, up from 4.4 million in 2022. The report also estimates that 6.13 million people with mild symptoms, such as memory impairment, will be targeted by donanemab by 2040.
Traditionally, Alzheimer’s treatments focused on symptom relief rather than addressing the disease’s underlying causes. With new drugs like lecanemab and donanemab, patients now have options to start treatment earlier and slow disease progression.
Together with emerging technologies like blood tests for early Alzheimer’s detection, these drugs are expected to help manage the increasing number of dementia and neurodegenerative disease cases.
