Eisai on Monday said it has won approval of its new Alzheimer’s disease treatment Leqembi in its home country of Japan, the second nation to clear the antibody drug after the U.S.
As in the U.S., Leqembi is approved in Japan to treat mild cognitive impairment and dementia due to Alzheimer’s. Recent testing showed the drug, which targets a protein called amyloid that’s thought to be a primary culprit in the disease, slowed patients’ cognitive and functional decline by about one-quarter compared to a placebo.
That evidence led the Food and Drug Administration, which in January had given Leqembi a conditional clearance, to grant the drug full approval in July, opening the door to wider use of the therapy.
Leqembi is also under regulatory review in the EU, the U.K. and half a dozen other countries. Eisai is partnered with Biogen on the drug, but leads development and regulatory submissions globally.
Under the approval granted by Japan’s Ministry of Health, Labour and Welfare, Eisai will conduct a post-marketing study of patients treated with Leqembi commercially, and work with physicians to ensure the drug’s most prominent side effect, known as ARIA, is appropriately managed.
One of Japan’s largest drugmakers, Eisai has long been invested in Alzheimer’s research, and was previously more closely partnered with Biogen on another Alzheimer’s drug called Aduhelm. Data supporting that treatment were controversial, and the drug’s launch never got off the ground, leading Biogen to abandon marketing it in the U.S.
Expectations are much higher for Leqembi, which analysts predict could eventually earn billions of dollars in annual sales.
Eisai is counting on the drug’s success, and recently restructured the organization and leadership of the division overseeing its Alzheimer’s business. Earlier this month it launched a new subsidiary, Theoria Technologies, to build a “dementia ecosystem” by developing risk prediction and patient monitoring tools.