Efficacy of Mavacamten in Patients With Symptomatic Latent Obstructive Hypertrophic Cardiomyopathy

Efficacy of Mavacamten in Patients With Symptomatic Latent Obstructive Hypertrophic Cardiomyopathy: A Randomized Controlled Trial

This study aimed to evaluate the efficacy and safety of Mavacamten compared to no treatment in patients with symptomatic latent obstructive hypertrophic cardiomyopathy. The trial was randomized into two groups: Mavacamten group and Non-Mavacamten group. Over the 30-week treatment period, patients underwent a series of assessments at predefined time points, including transthoracic echocardiography, electrocardiogram (ECG), Holter monitoring, NYHA functional classification, Kansas City Cardiomyopathy Questionnaire (KCCQ), and cardiac biomarkers.

Study Overview

• Status: Active, not recruiting
• Conditions: HCM - Hypertrophic Cardiomyopathy; Mavacamten
• Intervention / Treatment: Drug: mavacamten

• Study Type: Interventional
• Enrollment (Estimated): 78
• Phase: Not Applicable

Contacts and Locations

Study Locations

• China
  • Shanghai, China
    • Shanghai Chest Hospital

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

1. Age ≥18 years.
2. Weight greater than 45 kg.
3. Adequate acoustic windows to allow for accurate transthoracic echocardiograms (TTEs).
4. Diagnosis of latent obstructive hypertrophic cardiomyopathy, in accordance with the current guidelines of the American College of Cardiology Foundation/American Heart Association, European Society of Cardiology, and Chinese Society of Cardiology.
5. Left ventricular ejection fraction (LVEF) ≥55% at rest, confirmed by the echocardiography core laboratory.
6. New York Heart Association (NYHA) Class II or III symptoms at the time of screening.
7. Resting oxygen saturation ≥90% at the time of screening.

Exclusion Criteria:

1. Any acute or severe comorbidities (e.g., severe infections or hematological, renal, metabolic, gastrointestinal, or endocrine dysfunction).
2. Currently using or having used prohibited medications within 14 days prior to screening, such as cytochrome CYP2C19 inhibitors (e.g., omeprazole or esomeprazole) or strong CYP3A4 inhibitors.
3. Life expectancy of less than 1 year.
4. Pregnant or breastfeeding women.
5. History of syncope or sustained ventricular tachyarrhythmia during exercise within the past 6 months.
6. Atrial fibrillation (AF).
7. Patients currently receiving or planning to receive treatment with disopyramide, cibenzoline, ranolazine, or a combination of beta-blockers with verapamil or diltiazem.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Mavacamten Group; Patients in this group were treated with Mavacamten, starting at an initial dose of 2.5 mg, administered orally once daily. Subsequent doses were adjusted based on changes in pressure gradients and cardiac function observed during follow-up.	Drug: mavacamten; Patients in this group were treated with Mavacamten, starting at an initial dose of 2.5 mg, administered orally once daily. Subsequent doses were adjusted based on changes in pressure gradients and cardiac function observed during follow-up.
No Intervention: Control Group; Patients in this group did not receive Mavacamten treatment and were instead managed with traditional therapies of their choice, such as beta-blockers or calcium channel blockers.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The change in peak left ventricular outflow tract (LVOT) gradient	The change in peak left ventricular outflow tract (LVOT) gradient, determined by Doppler echocardiography, during exercise or pharmacologic provocation from baseline to week 30.	From baseline to week 30.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The proportion of patients with a peak left ventricular outflow tract (LVOT) gradient of less than 30 mmHg.	The proportion of patients with a peak left ventricular outflow tract (LVOT) gradient of less than 30 mmHg during exercise or pharmacologic provocation at week 30.	At week 30.
The proportion of patients with a peak left ventricular outflow tract (LVOT) gradient of less than 50 mmHg.	The proportion of patients with a peak left ventricular outflow tract (LVOT) gradient of less than 50 mmHg during exercise or pharmacologic provocation at week 30.	At week 30.
The proportion of patients with at least a one-class improvement in NYHA functional classification.	The proportion of patients with at least a one-class improvement in NYHA functional classification at week 30.	At week 30.
The change in the Kansas City Cardiomyopathy Questionnaire Clinical Summary Score (KCCQ-CSS).	The change in the Kansas City Cardiomyopathy Questionnaire Clinical Summary Score (KCCQ-CSS) from baseline to week 30.	From baseline to week 30.
The change in N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels.	The change in N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels from baseline to week 30.	From baseline to week 30.
The change in high-sensitivity cardiac troponin I (hs-cTnI) levels.	The change in high-sensitivity cardiac troponin I (hs-cTnI) levels from baseline to week 30.	From baseline to week 30.
Key safety endpoints	Key safety endpoints include the incidence and severity of treatment-emergent adverse events (TEAEs) and serious adverse events (SAEs).	From baseline to week 30.

Collaborators and Investigators

• Sponsor: Xu Liu

Study record dates

Study Major Dates

• Study Start (Actual): April 20, 2025
• Primary Completion (Estimated): February 1, 2026
• Study Completion (Estimated): February 1, 2026

Study Registration Dates

• First Submitted: April 20, 2025
• First Submitted That Met QC Criteria: April 20, 2025
• First Posted (Actual): April 27, 2025

Study Record Updates

• Last Update Posted (Actual): April 27, 2025
• Last Update Submitted That Met QC Criteria: April 20, 2025
• Last Verified: April 1, 2025

More Information

Terms related to this study

• Keywords: Mavacamten; HCM
• Additional Relevant MeSH Terms: Aortic Valve Disease; Cardiovascular Diseases; Pathological Conditions, Anatomical; Heart Diseases; Heart Valve Diseases; Aortic Stenosis, Subvalvular; Aortic Valve Stenosis; Cardiomyopathies; Cardiomyopathy, Hypertrophic; Hypertrophy
• Other Study ID Numbers: MVLOHCM

Drug and device information, study documents

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