What is Mavacamten?

Mavacamten (development code MYK-461) is a first-in-class, selective, allosteric inhibitor of cardiac myosin. It is the first pharmacological agent approved to target the underlying pathophysiology of hypertrophic cardiomyopathy (HCM) —a condition characterized by excessive cardiac muscle contraction, hypercontractility, and impaired relaxation (diastolic dysfunction).

Mechanism of action: Mavacamten binds selectively to the catalytic domain of cardiac myosin ATPase, reducing the number of myosin heads available for actin binding. This decreases cardiac contractility, reduces left ventricular outflow tract (LVOT) gradient, and improves diastolic filling.

Chemical structure highlights:

• Small molecule (MW 273.33)

• Allosteric modulator (not ATP-competitive)

• Highly selective for cardiac myosin (vs. smooth muscle or skeletal myosin)

• Oral bioavailability (well-absorbed)

Synonym：MYK-461(SAR-439152);SAR439152;SAR439152;SAR-439152;SAR-439152;SAR439152;SAR439152;MYK-461;MYK461;MYK461;MAVACAMTEN;MYK-461-Mavacamten|SAR439152;Mavacamten(MYK-461;2,4(1H,3H)-Pyrimidinedione,3-(1-methylethyl)-6-[[(1S)-1-phenylethyl]amino]-