TOKYO: Hopes are high in Japan that the new Alzheimer’s disease drug developed jointly by Eisai Co. and US biopharmaceutical company Biogen Inc. will ease burdens on patients and their families.

Dementia is a serious social problem in Japan, where the population is aging rapidly, as it involves physically demanding caregiving by family members and high treatment costs.

The new remedy, aducanumab, is expected to ease such burdens, while there are concerns that it may drive up the country’s medical costs.

The number of people with dementia in Japan is seen rising from 4.62 million in 2012 to 7.3 million in 2025. Some experts estimate that two in three of them will have Alzheimer’s disease.

According to Eisai and others, the disease cost Japanese society over 12 trillion yen in 2018, more than half of which was related to caregiving by family members.

Aducanumab gained U.S. regulatory approval Monday, becoming the world’s first approved drug that directly works on substance believed to cause Alzheimer’s disease.

In Japan, an application for health ministry approval of the drug was filed in December last year. Patients and their families have high expectations.

Aducanumab would help “greatly reduce the costs related to family care,” Eisai CEO Haruo Naito said.

The drug’s contribution to profits will also be significant at Eisai and Biogen.

The number of patients suited for treatment with the drug is estimated at one million to 2 million in the United States and one million in Japan.

Based on U.S. prices, annual costs per patient are put at 56,000 dollars, or some 6.1 million yen. If 100,000 patients receive the treatment, annual sales will exceed 600 billion yen.

Usually, pharmaceutical products are considered a blockbuster if annual sales exceed 100 billion yen. Some speculate that aducanumab will generate annual sales of up to around 1 trillion yen.

Following the U.S. approval, Eisai drew hefty purchases on the Tokyo Stock Exchange on Tuesday, going limit-up to 9,251 yen per share, a new high for the year.

JIJI Press