Less than 20% of people who showed interest in taking new medications for Alzheimer¡¯s disease went on to receive one, mainly because they were not medically eligible or they decided against it for fear of side effects, a new study by Japanese researchers has found.
While Japan¡¯s universal health care covers lecanemab and donanemab, medical requirements and concerns for costs and side effects on the part of patients and their families mean many end up not receiving the medications, the researchers said.
In Japan, where these drugs cost about ?3 million per patient annually, the high-cost medical benefit program also keeps the out-of-pocket expenses down, though the caps for such expenses are scheduled to go up in stages starting in August.
A research team at the Tokyo Metropolitan Institute for Geriatrics and Gerontology (TMIG) analyzed individuals who visited its clinic, established specifically for the so-called disease-modifying therapy, between December 2023 and April 2025.
Lecanemab and donanemab, two such drugs introduced in Japan in 2023 and 2024, respectively, aim to slow the progression of the neurodegenerative disease by removing a protein called amyloid-beta from the brain, whose buildup is believed to contribute to the death of brain cells.
Of the 456 patients interested in receiving the anti-amyloid therapy, 247 were excluded at the first screening, largely because their disease conditions were too advanced to be eligible for the therapy. In the end, 87 people, or 19%, proceeded to receive the therapy.
Apart from those who did not meet the eligibility requirements, 93 people decided not to proceed after the informed consent phase. Concerns about the drugs¡¯ side effects topped the reasons cited, followed by the burden of visiting the clinic regularly and the cost of treatment.
The infusion drugs have been linked to some serious side effects like brain bleeding and swelling.
Those over the age of 75, those with very early symptoms, and male patients were particularly likely to avoid the treatment.
¡°Taking into account not only biological factors but also patients¡¯ own choices about whether to pursue treatment, I don¡¯t feel that having about 20% of those who visit the clinic go on to receive treatment is particularly low,¡± said Ryoko Ihara, a researcher at TMIG who led the study.
¡°That said, we are still not reaching enough people at the very early stage, who are best suited for anti-amyloid beta antibody therapies.¡±
was published last month in the journal Alzheimer¡¯s & Dementia: Diagnosis, Assessment & Disease Monitoring.
?
?
With your current subscription plan you can comment on stories. However, before writing your first comment, please create a display name in the Profile section of your subscriber account page.