'Fundamental Dementia Treatment' Leqembi, Imminent Arrival in Korea

Rekemvi (lecanemab), an antibody treatment for Alzheimer's dementia jointly developed by Biogen and Eisai, has been approved in South Korea. It has attracted attention as the first fundamental dementia treatment drug to land domestically that has been confirmed to slow the cognitive decline speed of dementia patients, unlike existing symptomatic therapies.

Biogen and Eisai's Alzheimer's dementia treatment 'Leqembi (generic name: lecanemab)' [Image source=AP Yonhap News]

The Ministry of Food and Drug Safety (Commissioner Oh Yu-kyung) announced on the 24th that it has approved Rekemvi, a new drug for Alzheimer's disease by Korea Eisai. Rekemvi is a medicine whose safety and efficacy have been confirmed for the treatment of patients with mild Alzheimer's disease or mild cognitive impairment (MCI), a pre-dementia stage.

In the Phase 3 clinical trial results, the Clinical Dementia Rating-Sum of Boxes (CDR-SB) score, which evaluates cognitive functions related to dementia scales such as memory, judgment, and home life, showed that cognitive decline was delayed by 27% compared to the placebo group over 18 months.

It has a mechanism that reduces the deposition of amyloid beta (Aβ) protein in the brain, considered one of the most likely causes of Alzheimer's dementia, thereby slowing the progression of dementia. However, its efficacy and safety have not been confirmed for patients who have already progressed to severe dementia.

Additionally, the Ministry of Food and Drug Safety warned that side effects such as amyloid-related imaging abnormalities (ARIA) may occur. Dementia treatments like Rekemvi that remove Aβ protein can cause issues such as cerebral microbleeds and brain edema during the process of removing proteins attached to blood vessels. The Ministry emphasized, "ARIA is generally asymptomatic but can cause headaches, confusion, dizziness, etc., and usually disappears over time. Rarely, serious and life-threatening cases such as seizures and epilepsy may occur, so regular imaging monitoring such as magnetic resonance imaging (MRI) according to approval requirements is necessary."

The Ministry of Food and Drug Safety has also collaborated with the Health Insurance Review and Assessment Service to facilitate Rekemvi's rapid market entry. This utilized the 'approval-reimbursement evaluation linkage' system, which allows an application for reimbursement decision to the Health Insurance Review and Assessment Service based on the Ministry's safety and efficacy review results before product approval. Through this, it is expected that the insurance price evaluation period will be shortened, enabling faster market access.