One-year real-world experience with mavacamten and its physiologic effects on obstructive hypertrophic cardiomyopathy
Daniel Seung Kim1,2,3,4,5, Emily L Chu1, Emily E Keamy-Minor1
1Division of Cardiovascular Medicine, Department of Medicine, Stanford University School of Medicine, Stanford, CA, United States.
Insights
Mavacamten, a novel cardiac myosin inhibitor, shows significant improvements in obstructive hypertrophic cardiomyopathy (oHCM) patients. Real-world data indicate safety and efficacy, with rare adverse events and notable symptom relief.
Area of Science:
- Cardiology
- Pharmacology
Background:
- Hypertrophic cardiomyopathy with obstructive physiology (oHCM) is a significant cardiovascular condition.
- Cardiac myosin ATPase inhibitors represent a novel therapeutic class for oHCM.
Purpose of the Study:
- To evaluate the real-world safety and efficacy of mavacamten in patients with oHCM.
- To assess the impact of mavacamten on clinical parameters and patient-reported outcomes.
Main Methods:
- Retrospective analysis of 50 oHCM patients treated with mavacamten at a tertiary care center.
- Monitoring of echocardiographic parameters, New York Heart Association (NYHA) class, and adverse events.
Main Results:
- Significant improvements observed in wall thickness, mitral regurgitation, left ventricular outflow tract obstruction, and NYHA class.
- Minimal impact on arrhythmia burden and contractility; clinically insignificant mean decrease in left ventricular ejection fraction (LVEF).
- Two patients required temporary mavacamten discontinuation due to LVEF < 50%; adverse events were rare and not directly linked to mavacamten.
Conclusions:
- Mavacamten is safe and effective in a real-world setting for treating oHCM.
- The drug demonstrates significant clinical benefits with a favorable safety profile in this patient cohort.
- A multidisciplinary approach facilitated rapid access to this novel therapy for oHCM patients.
Abstract:
Mavacamten is a first-in-class cardiac myosin ATPase inhibitor, approved by the United States Food and Drug Administration for the treatment of hypertrophic cardiomyopathy with obstructive physiology (oHCM). Here, we present the real-world use of mavacamten in 50 patients with oHCM at a tertiary care referral center. In both our highlighted case and in our aggregate data, we report significant improvement in wall thickness, mitral regurgitation, left ventricular outflow tract obstruction and New York Heart Association symptom class. Moreover, in our center's experience, neither arrhythmia burden, nor contractility have worsened in the vast majority of patients: we note a clinically insignificant mean decrease in left ventricular ejection fraction (LVEF), with only two patients requiring temporary mavacamten discontinuance for LVEF < 50%. Adverse events were rare, unrelated to mavacamten itself, and seen solely in patients with disease too advanced to have been represented in clinical trials. Moreover, our multidisciplinary pathway enabled us to provide a large number of patients with a novel closely-monitored therapeutic within just a few months of commercial availability. These data lead us to conclude that mavacamten, as a first-in-class cardiac myosin inhibitor, is safe and efficacious in real-world settings.
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