Carefully observe effectiveness of new drug for Alzheimer’s disease

The Yomiuri Shimbun

12:15 JST, June 17, 2021

Will this lead to the establishment of a new treatment for Alzheimer’s disease, the most common form of dementia? In order to use this drug effectively in Japan, the results it produces must be carefully observed.

The U.S. Food and Drug Administration (FDA) has approved aducanumab, a drug for the early stages of Alzheimer’s disease, which was developed jointly by U.S. pharmaceutical company Biogen Inc. and Japanese firm Eisai Co. This is the first time in 18 years that a new drug for Alzheimer’s disease has been approved in the United States.

There are believed to be 50 million people with dementia worldwide, and Alzheimer’s disease accounts for 60% to 70% of this number. There have so far been drugs that temporarily improve symptoms, but no fundamental cure has been found.

Alzheimer’s disease involves the accumulation of abnormal proteins in the brain that gradually destroy neurons. Aducanumab is the world’s first drug to remove these proteins. It can be called an epoch-making drug, as it might prevent the disease from progressing for a long time.

However, the results of clinical trials to examine its effectiveness have left some issues to be resolved. Of the two trials, one cut decline in cognitive function by 20%, while the other failed to prove effective. The dosage is thought to have been insufficient.

Saying the benefits of the drug for people with Alzheimer’s disease outweigh the risks of the therapy, the FDA decided to approve aducanumab on condition that it be retested after sales are launched. Some people in the United States disapprove of this decision. Pharmaceutical companies need to thoroughly examine the effectiveness of the drug.

In Japan, there are about 2 million to 2.5 million people in the early stages of Alzheimer’s disease, and more than 1 million people are expected to be eligible for taking aducanumab. It was submitted for approval in Japan in December last year. Thorough screenings should be conducted based on developments in the United States.

Special diagnostic imaging equipment is needed to detect the abnormal proteins in the brain, and testing facilities for that purpose are limited. A method to identify the proteins through blood tests has been developed, and it is hoped the method will be put into practical use as soon as possible.

Aducanumab is expected to cost $56,000 (about ¥6.1 million) a year per patient in the United States. If it is covered by the health insurance system in Japan, there are concerns doing so will put pressure on the nation’s medical finances.

If the drug proves effective, nursing care costs and the burden on family members for nursing care can be reduced, even if medical costs increase. It is necessary to estimate how much nursing care costs can be reduced as a result of using aducanumab, as well as consider what a fair price for the new drug is and the requirements for patients to be covered by the health insurance system.

Other drugs are being developed for Alzheimer’s disease. The number of patients likely will continue to increase due to the aging population. It is also important to conduct further studies to eradicate or prevent this disease in the future.

— The original Japanese article appeared in The Yomiuri Shimbun on June 17, 2021.