# Net health benefit of mavacamten for the treatment of Chinese patients with obstructive hypertrophic cardiomyopathy: a model-based economic evaluation

## TL;DR

This study shows that mavacamten improves survival and quality of life for Chinese patients with obstructive heart disease compared to standard treatments.

## Contribution

The study evaluates the health benefits of mavacamten in Chinese patients with obstructive hypertrophic cardiomyopathy using a model-based economic evaluation.

## Key findings

- Mavacamten ± BB/CCBs showed better health outcomes with 15.76 life-years versus 14.40 with BB/CCB monotherapy.
- Quality-adjusted life-years (QALYs) were higher with mavacamten (13.69 vs. 11.38).
- Mavacamten provides clinically meaningful improvements in survival and quality of life for obstructive HCM patients.

## Abstract

Obstructive hypertrophic cardiomyopathy (HCM) is a cardiovascular disorder characterized by significant symptom burden. This study aims to evaluate the net clinical benefit of mavacamten (a first-in-class cardiac myosin inhibitor) ± beta-blockers/calcium channel blockers (BB/CCBs) compared to BB/CCB monotherapy for Chinese patients with obstructive HCM.

A five-state Markov model (NYHA classes I–IV and death) was developed from a Chinese healthcare system perspective. Patients were initialised in NYHA II or III states, mirroring the baseline distribution in the EXPLORER-CN trial (NCT05174416). State transitions were simulated using cycle-specific probabilities derived from trial data and validated extrapolation assumptions. All-cause mortality risks incorporated disease-specific and extra surgical mortality rates. Treatment sequencing rules reflected escalation pathways (e.g., non-response, adverse events, or eligibility for septural reduction therapy [SRT]), informed by Chinese clinical practice. Health utilities were mapped algorithmically from EXPLORER-CN patient-level EQ-5D responses.

Over a lifetime horizon, mavacamten ± BB/CCBs demonstrated superior health outcomes versus BB/CCB monotherapy, with incremental gains in life-years (15.76 vs. 14.40) and quality-adjusted life-years (QALYs: 13.69 vs. 11.38).

Mavacamten provides substantial health benefits for Chinese obstructive HCM patients, including clinically meaningful improvements in survival and quality-of-life metrics relative to standard care.