(097) Cost-Effectiveness of Lecanemab (Leqembi) for Individuals With Early-Stage Alzheimer’s Disease

Background: Little is known regarding the cost-effectiveness of lecanemab (Leqembi), a monoclonal antibody approved for treatment of mild cognitive impairment or mild dementia due to Alzheimer’s Disease (AD).

Objectives: To quantify the cost-effectiveness of lecanemab and how this varies based on the accuracy of AD testing and individuals’ APOE ε4 status.

Methods: Our study cohort comprised of patients with characteristics largely mirroring the CLARITY AD trial. Seven alternative test-treat-target strategies defined by combinations of testing approaches (Positron Emission Testing [PET], Cerebrospinal Fluid [CSF] or plasma assays), treatment choices (Standard-of-care [SoC] alone or lecanemab in addition to SoC), and targeting strategies (targeting APOE ε4 non-carriers or heterozygous patients or not) were compared. We developed a hybrid decision tree-Markov cohort model using a cycle length of 6 months and a lifetime horizon with five health states with five states: (1) mild cognitive impairment (Clinical Dementia Rating-Sum of Boxes [CDR-SB] 0-4.5); (2) mild dementia (CDR-SB 4.6-9.5); (3) moderate dementia (CDR-SB 9.6-16); (4) severe dementia (CDR-SB >16); and (5) death. Effectiveness was measured by quality adjusted life years (QALYs) and costs from third-party and societal perspectives estimated in 2022 US dollars over a lifetime horizon. We calculated the Incremental Cost Effectiveness Ratio (ICER) as the difference between the overall costs of any two strategies divided by the difference between the total QALYs gained. A strategy was considered cost-effective if its ICER was below the willingness-to-pay threshold (WTP) of $100,000 per QALY.

Results: Among the seven test-treat-target strategies, SoC alone is the optimal strategy from a cost-effectiveness perspective. Neither targeted lecanemab treatment nor treatment unrestricted by APOE ε4 genotype is cost-effective versus standard of care alone, regardless of the test used to diagnose patients with early-stage Alzheimer’s disease. However, CSF assay followed by targeted treatment becomes cost-effective if lecanemab is priced below $5,100 per year. These results are robust to accuracy of diagnostic testing as well as rates of lecanemab discontinuation and adverse events.

Conclusions: Neither targeted lecanemab treatment nor treatment unrestricted by APOE ε4 genotype is cost-effective versus standard of care alone for patients with mild cognitive impairment or mild dementia due to AD. Lecanemab would be cost effective in some settings if priced below $5,100 per year.