Recent trend in the therapy of hypertrophic cardiomyopathy: Cardiac myosin inhibitors

Abstract

Cardiac myosin inhibitors are a new class of drugs that have recently been approved in obstructive hypertrophic cardiomyopathy. The main mechanism of action is to reduce the pathologically increased cardiac hypercontractility. Current drug therapies have not been demonstrated to modify the natural progress of the disease. Mavacamten is the first approved oral drug to reduce the generation of actin-myosin cross-bridges, thus inhibiting the probability of systolic and diastolic cross-bridge occurence. In clinical studies, it has been shown that mavacamte increases exercise capacity, reduces the left ventricle outflow tract pressure and improves health status by regressing symptoms. However, mavacamten therapy requires continuous monitoring due to the risk of exacerbation of heart failure symptoms. Altertative cardiac myosin inhibitors, aficamten, MYK-224, and MYK-581 are currently under investigation. These drugs have provided a novel treatment approach for obstructive hypertrophic cardiomyopathy. Further studies will lead to the development of targeted therapies that have the ability to reduce the natural course of this disease.

Keywords

• cardiac myosin ATPase inhibition
• hypertrophic cardiomyopathy
• mavacamten
• aficamten
• MYK-224
• MYK-581

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