Mavacamten in Adult Patients With Obstructive Hypertrophic Cardiomyopathy (MAVA-HCM)

Mavacamten for Improving Cardiac Function and Clinical Outcomes in Adult Patients With Obstructive Hypertrophic Cardiomyopathy: A Retrospective Cohort Study

This retrospective cohort study aims to evaluate the clinical efficacy and safety of mavacamten in adult patients with obstructive hypertrophic cardiomyopathy (oHCM). A total of 222 patients were included and categorized based on treatments received in routine clinical practice into a mavacamten group and a standard therapy group.

The primary outcome is the change in resting left ventricular outflow tract (LVOT) gradient at Week 30. Secondary outcomes include changes in Valsalva LVOT gradient, New York Heart Association (NYHA) functional class, cardiac biomarkers, and echocardiographic parameters. Safety outcomes include adverse events and left ventricular systolic dysfunction.

This study provides real-world evidence on the effectiveness and safety of mavacamten in Chinese patients with oHCM.

Study Overview

• Status: Completed
• Conditions: Obstructive Hypertrophic Cardiomyopathy (oHCM); Hypertrophic Cardiomyopathy (HCM)
• Intervention / Treatment: Drug: mavacamten

Detailed Description

Hypertrophic cardiomyopathy (HCM) is a genetic cardiac disorder characterized by left ventricular hypertrophy, with approximately two-thirds of patients presenting with obstructive physiology. Obstructive hypertrophic cardiomyopathy (oHCM) is associated with significant morbidity due to left ventricular outflow tract (LVOT) obstruction.

Mavacamten, a first-in-class cardiac myosin inhibitor, directly targets the underlying pathophysiology of oHCM by reducing excessive myosin-actin cross-bridge formation. Although previous randomized clinical trials, such as EXPLORER-CN, have demonstrated its efficacy, real-world data in Chinese populations remain limited.

This study is a retrospective cohort study conducted at Fuwai Central China Cardiovascular Hospital. Patients were not assigned to interventions. Instead, they were categorized based on treatments received in routine clinical practice. Eligible adult patients with oHCM who initiated mavacamten therapy were included in the treatment group, while patients receiving standard pharmacological therapy served as the control group.

Clinical data were collected from January 2024 to May 2025, with final database lock completed in June 2025. Baseline characteristics, echocardiographic parameters, and laboratory biomarkers were obtained from medical records.

The primary endpoint was the change in resting LVOT peak gradient at Week 30 compared with baseline. Secondary endpoints included changes in Valsalva LVOT gradient, NYHA functional class improvement, NT-proBNP, high-sensitivity cardiac troponin I (hs-cTnI), left ventricular ejection fraction (LVEF), and tricuspid annular plane systolic excursion (TAPSE). Safety endpoints included adverse events, serious adverse events, treatment discontinuation, and reduction of LVEF below 50%.

This study aims to provide real-world evidence regarding the clinical effectiveness and safety of mavacamten in adult patients with oHCM in China.

• Study Type: Observational
• Enrollment (Actual): 222

Contacts and Locations

Study Locations

• China
  • Henan
    • Zhengzhou, Henan, China, 450000
      • Fuwai Central China Cardiovascular Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Adult patients diagnosed with obstructive hypertrophic cardiomyopathy who received treatment at Fuwai Central China Cardiovascular Hospital between January 2024 and May 2025 in routine clinical practice.

Description

Inclusion Criteria:

• Age ≥18 years
• Diagnosis of hypertrophic cardiomyopathy
• NYHA functional class II-III
• First-time treatment with mavacamten

Exclusion Criteria:

• Known hypersensitivity to mavacamten or its components
• Left ventricular ejection fraction (LVEF) <55%
• Septal reduction therapy within 6 months prior to enrollment
• Presence of other conditions requiring long-term anticoagulation
• Pregnancy or breastfeeding
• Any condition deemed unsuitable by the investigator

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Mavacamten Group; Adult patients with obstructive hypertrophic cardiomyopathy (oHCM) who received mavacamten as part of routine clinical practice. Patients were not assigned to interventions but were categorized based on treatment received.	Drug: mavacamten; Mavacamten was administered as part of routine clinical care for patients with obstructive hypertrophic cardiomyopathy. This observational study did not assign interventions; instead, patients were categorized based on treatments received in real-world clinical practice. The initial dose was 2.5 mg once daily, with dose adjustments based on left ventricular ejection fraction and LVOT gradient as clinically indicated.; Other Names: Camzyos; Mai Fan Tuo
Standard Therapy Group; Adult patients with obstructive hypertrophic cardiomyopathy (oHCM) who received standard pharmacological therapy, including beta-blockers or non-dihydropyridine calcium channel blockers, in routine clinical practice.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Resting Left Ventricular Outflow Tract (LVOT) Peak Gradient at Week 30	Change from baseline in resting left ventricular outflow tract (LVOT) peak gradient measured by Doppler echocardiography (unit: mmHg). Higher values indicate greater obstruction.	Baseline to Week 30

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Valsalva-Induced Left Ventricular Outflow Tract (LVOT) Peak Gradient at Week 30	Change from baseline in LVOT peak gradient induced by the Valsalva maneuver measured by Doppler echocardiography (unit: mmHg). Higher values indicate greater obstruction.	Baseline to Week 30
Proportion of Participants with Improvement in New York Heart Association (NYHA) Functional Classification at Week 30	Proportion of participants achieving at least one class improvement in New York Heart Association (NYHA) functional classification compared with baseline. NYHA class ranges from I to IV, where higher classes indicate worse functional status.	Baseline to Week 30
Change in N-terminal pro-B-type Natriuretic Peptide (NT-proBNP) Levels at Week 30	Change from baseline in N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels (unit: pg/mL). Higher values indicate worse cardiac function.	Baseline to Week 30
Change in High-Sensitivity Cardiac Troponin I (hs-cTnI) Levels at Week 30	Change from baseline in high-sensitivity cardiac troponin I (hs-cTnI) levels (unit: ng/L). Higher values indicate greater myocardial injury.	Baseline to Week 30
Change in Left Ventricular Ejection Fraction (LVEF) at Week 30	Change from baseline in left ventricular ejection fraction (LVEF) measured by echocardiography (unit: %). Higher values indicate better cardiac systolic function.	Baseline to Week 30
Change in Tricuspid Annular Plane Systolic Excursion (TAPSE) at Week 30	Change from baseline in tricuspid annular plane systolic excursion (TAPSE) measured by echocardiography (unit: mm). Higher values indicate better right ventricular function.	Baseline to Week 30
Incidence of Adverse Events	Number and proportion of participants experiencing any adverse events.	Up to Week 30
Incidence of Serious Adverse Events	Number and proportion of participants experiencing serious adverse events.	Up to Week 30
Incidence of Treatment Discontinuation Due to Adverse Events	Number and proportion of participants who discontinued treatment due to adverse events.	Up to Week 30
Incidence of Left Ventricular Ejection Fraction Reduction Below 50%	Number and proportion of participants with LVEF <50% during treatment.	Up to Week 30

Collaborators and Investigators

• Sponsor: Chinese Academy of Medical Sciences, Fuwai Hospital

Study record dates

Study Major Dates

• Study Start (Actual): January 1, 2024
• Primary Completion (Actual): May 30, 2025
• Study Completion (Actual): June 30, 2025

Study Registration Dates

• First Submitted: April 8, 2026
• First Submitted That Met QC Criteria: April 8, 2026
• First Posted (Actual): April 14, 2026

Study Record Updates

• Last Update Posted (Actual): April 17, 2026
• Last Update Submitted That Met QC Criteria: April 14, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: Mavacamten; Echocardiography; Hypertrophic Cardiomyopathy; Cardiac function; Real-world study; Retrospective cohort; LVOT obstruction
• Additional Relevant MeSH Terms: Aortic Valve Disease; Cardiovascular Diseases; Heart Diseases; Heart Valve Diseases; Ventricular Outflow Obstruction; Cardiomyopathies; Aortic Stenosis, Subvalvular; Aortic Valve Stenosis; Ventricular Outflow Obstruction, Left; Cardiomyopathy, Hypertrophic; MYK-461
• Other Study ID Numbers: FW-CHC-HCM-2024-01

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED
• IPD Plan Description: Individual participant data (IPD) sharing has not yet been determined. Due to the retrospective nature of this study and the use of de-identified clinical data, any potential data sharing will be considered in accordance with institutional policies, ethical approvals, and applicable data protection regulations.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No