Aficamten: A New Cardiac Myosin Inhibitor for Hypertrophic Obstructive Cardiomyopathy

After the approval of mavacamten, a novel cardiac myosin inhibitor for symptomatic hypertrophic obstructive cardiomyopathy, a new medication in the same group is getting ready. Hypertrophic obstructive cardiomyopathy is a genetically determined disease of the heart muscle in which gross thickening of the wall between the two lower chambers of the heart obstructs outflow of blood from the left sided chamber known as left ventricle. This can cause breathlessness and giddiness on exertion and sometimes chest pain. It has also the potential to cause sudden death due to life threatening heart rhythm disorders. Mavacamten and aficamten decreases the contractile force of the heart muscle and thereby reduces the chance of obstruction to outflow of blood from the left ventricle. A recent clinical trial published in the leading medical journal New England Journal of Medicine has documented the beneficial effects of aficamten.

Compared to mavacamten, aficamten has lesser potential for drug-drug interactions. Half-life of aficamten in blood is lower so that dose titration is possible within shorter periods than mavacamten, to individualize the dose schedule. The suppressive effect of aficamten on the pumping action of the heart is lower by design so that there is less chance of development of heart failure due to reduced pump function while increasing the dose. In the recent study report there was no loss of benefit in those who were on another group of medications for hypertrophic cardiomyopathy known as beta blockers. It was there in studies on mavacamten earlier.