Economic Evaluation of Lecanemab for Early Symptomatic Alzheimer's Disease in South Korea

Background/Objectives Alzheimer's disease (AD) exerts a considerable economic burden on South Korea's aging population. Lecanemab, an amyloid-targeting therapy, has demonstrated efficacy in mitigating cognitive decline in early-stage AD but remains non-reimbursed in South Korea due to concerns over its economic feasibility. This study aimed to examine the cost-effectiveness of lecanemab using nationwide claims data for cost estimation within the South Korean healthcare system. Considering the substantial societal burden of AD, we also evaluated the cost-effectiveness of lecanemab from a limited societal perspective. Methods A Markov state transition cohort model was developed to compare costs and outcomes of lecanemab combined with standard of care (SoC) versus SoC alone. The model simulated five stages of AD progression: mild cognitive impairment, mild AD, moderate AD, severe AD, and death. Transition probabilities between health states were derived from data provided by the National Alzheimer’s Coordinating Center. Formal medical costs and long-term care costs were obtained from the national claims database, while drug cost and other medical expenses were derived from previous studies. Additional cost components such as opportunity cost of caregiver time, out-of-pocket expenses, and time and travel costs for hospital visits were included in the limited societal perspective. Korean-specific utilities for patients and caregivers differentiated by states of AD progression and care settings were obtained from the published literature. Effectiveness was measured in quality-adjusted life years (QALYs) over a lifetime horizon. Scenario analyses were conducted by varying compositions of the cohort, age of onset, and drug pricing. Results The incremental cost-effectiveness ratio (ICER) of lecanemab combined with SoC was 198,171,820 Korean Won (KRW)/QALY from the healthcare payer perspective and 181,185,820 KRW/QALY from the limited societal perspective, which significantly exceeded South Korea’s willingness-to-pay (WTP) threshold of 30 million KRW/QALY. Sensitivity analyses revealed that the ICER was highly influenced by variations in treatment effect and discount rates. The result of scenario analyses suggested that targeting lecanemab to patients with mild AD or implementing price reductions could substantially improve its cost-effectiveness. Conclusions Lecanemab's high cost poses a challenge to its inclusion in the National Health Insurance formulary under South Korea’s current WTP thresholds. Strategic price adjustments and patient targeting are essential to enhance its economic viability. These findings provide valuable insights for policymakers and stakeholders in balancing treatment outcomes and resource allocation for AD management.