Cost-Effectiveness of Mavacamten for the Treatment of Patients with Symptomatic Obstructive Hypertrophic Cardiomyopathy in the Netherlands

OBJECTIVES: There are currently no reimbursed disease targeting therapies in the Netherlands for symptomatic (New York Heart Association [NYHA] class II/III) obstructive hypertrophic cardiomyopathy (HCM). The objective is to assess the cost-effectiveness (CE) of mavacamten within the above indication in line with Zorginstituut Nederland (ZIN) health economic guidelines.

METHODS: The cost-effectiveness of mavacamten + standard of care (SoC) defined as beta-blockers/non-dihydropyridine calcium channel blockers, was compared with SoC using a five state (NYHA I-IV and death) Markov model adopting a societal perspective over a lifetime horizon. Patient population reflected baseline EXPLORER-HCM patients (mean starting age: 59 years). Progression through and patterns of treatment were informed by clinical trials, supplemented by literature. Treatment acquisition costs were derived from 2022 Z-index and NZa diagnosis-related group codes for pharmacological and surgical interventions, respectively. Indirect costs, encompassing caregiver, travel, and productivity costs, were based on tariffs, prior cardiovascular reimbursement submissions and local clinical expertise. Utilities were derived from EXPLORER-HCM based EQ-5D-5L data applying Dutch tariffs. Aligned with ZIN guidelines, discounting rates for costs and effects were 4% and 1.5%, respectively. Outcomes included incremental costs, quality-adjusted life years (QALYs), life years (LYs), and cost-effectiveness/utility ratios. Robustness of model results was tested with deterministic and probabilistic analyses and scenario analyses.

RESULTS: In a model aligned with ZIN health economic guidelines, addition of mavacamten (+SoC) vs SoC achieved +2.84 and +2.73 discounted incremental QALYs and LYs, respectively. Incremental, discounted costs were +€42,020 over a lifetime, driven by mavacamten treatment acquisition costs, offset by savings in healthcare resource utilisation and indirect costs. Mavacamten + SoC was cost-effective at a threshold of €20,000/QALY, derived using the proportional shortfall method, vs SoC at €14,819/QALY.

CONCLUSIONS: Treatment with mavacamten is a cost-effective strategy for managing adult symptomatic obstructive HCM and is an efficient use of healthcare resource in the Netherlands.