A Cost-Effectiveness Analysis for Treatments of Patients with Early Stage Huntington's Disease in the USA

Huntington's disease (HD) is a rare neurodegenerative condition caused by mutations in the huntingtin gene. Emerging therapies such as Tominersen and AMT-130 have potential to treat HD, highlighting the importance of evaluating their cost-effectiveness. This study evaluates the cost-effectiveness of Tominersen and AMT-130 versus standard of care (SoC) for early stage HD in the US.

A Markov model with four health states (early, middle, late, and death) was developed to estimate lifetime costs and benefits from a modified societal perspective, with death as an absorbing state. The model used 1-year cycle length with half-cycle correction, and an annual discount rate of 3% was used for all future costs and utilities. Health benefits were measured in quality-adjusted life years (QALYs). All costs were adjusted to 2024 US dollars. As per the incremental cost-effectiveness ratio (ICER) value assessment framework, a willingness-to-pay threshold (WTP) of $500,000/QALY gained was considered given that HD is a rare disease. Scenario analysis assessed the impact of adding value of hope to the base-case utility values. Deterministic and probabilistic sensitivity analyses were conducted to capture uncertainty across all model parameters.

Compared with SoC, Tominersen increased costs by $2.11 million and QALYs by 0.93, resulting in an ICER of $2.28 million per QALY gained, whereas AMT-130 increased costs by $1.49 million and QALYs by 5.23, resulting in an ICER of $285,703 per QALY gained in the base case. Probabilistic analysis showed AMT-130 had 80% probability of being cost-effective at $350,000/QALY gained.

From a modified US societal perspective, this analysis suggests that AMT-130 may be cost-effective relative to SoC, whereas Tominersen exceeds the WTP threshold of $500,000 per QALY gained. Further evidence on long-term effectiveness and durability is needed to inform policy and reimbursement decisions.