To estimate the cost-effectiveness of lecanemab versus standard of care (SoC) in patients with mild cognitive impairment (MCI) or mild dementia due to Alzheimer’s disease (AD), with confirmed beta-amyloid (Aβ) pathology, from a Canadian societal perspective.

The efficacy and safety of lecanemab have previously been evaluated in the Phase 3 randomized clinical trial, Clarity AD (NCT03887455). Despite this, the cost-effectiveness of lecanemab compared with the current SoC remains uncertain.

A Markov cohort model was developed, with health states determined by Clinical Dementia Rating-Sum of Boxes (CDR-SB) scores. Transitions between health states during month 0-18 were estimated from Clarity AD. Beyond month 18, results previously reported from analysis of National Alzheimer's Coordinating Center data were used, with relative efficacy for lecanemab in the form of the hazard ratio for time-to-worsening of CDR-SB, taken from Clarity AD Core Study. The model assumes a constant rate of discontinuation, and all patients would discontinue lecanemab after developing moderate AD, or upon institutionalization. The model included the effects of lost productivity and impact on carer health-related quality of life. Unit costs were taken from publicly available sources, and utility values for each health state were taken from published literature. A lifetime time horizon was adopted. Costs and benefits were both discounted at 1.5%.

Treatment with lecanemab was associated with an incremental cost of CAD 77,710 and a quality-adjusted life year (QALY) gain of 1.24. The incremental cost-effectiveness ratio (ICER) for lecanemab vs SoC was therefore estimated to be CAD 62,751 per QALY gained. The probability that lecanemab was cost-effective at a threshold of CAD 100,000 was estimated to be 88.5%.

Lecanemab represents a cost-effective option for the treatment for early AD from the Canadian societal perspective. The results of this analysis can be used to inform clinical and economic decision making.