In patients suffering with oHCM, myosin inhibition with MYQORZO, which is an allosteric and reversible inhibitor of cardiac myosin motor activity, lowers left ventricular outflow tract (LVOT) obstruction and cardiac contractility.
The US Prescribing Information for MYQORZO contains a boxed warning related to heart failure risk. The medication reduces left ventricular ejection fraction (LVEF) and may cause heart failure from systolic dysfunction.
Echocardiogram assessments are required before and during treatment to monitor systolic dysfunction, the company stated.
Initiation in patients with LVEF below 55% is not recommended. Dose reduction is advised if LVEF drops below 50% but remains at or above 40%. If LVEF falls below 40%, or if heart failure symptoms or worsened clinical status from systolic dysfunction occur, treatment interruption is advised, the company added.
Due to the risk of heart failure, MYQORZO is distributed through a controlled access programme under a Risk Evaluation and Mitigation Strategy (REMS), known as the MYQORZO REMS Programme.
MYQORZO is anticipated to be available in the US during the second half of January 2026.
Cytokinetics plans to assist US patients prescribed MYQORZO through the MYQORZO & You programme by providing support in navigating treatment, offering education on the disease and product, and providing support with insurance benefits investigations or financial help for those who qualify.
Cytokinetics president and CEO Robert Blum said: “This is a historic moment for our company and for the patients we serve, as we fulfill our promise to translate our science into medicines that may make a meaningful difference in patients’ lives. Our first FDA approval stands as a testament to the strength of our science and the bold, trailblazing research that has defined Cytokinetics’ leadership in muscle biology.
“I’m pleased that the approved label and REMS reflect the distinct characteristics of MYQORZO including a straightforward, flexible dosing regimen, no requirement for drug-drug interaction monitoring and a predictable safety profile. I am profoundly grateful for the many years of passion and persistence shown by patients with obstructive HCM, as well as healthcare professionals, advocates, partners and employees who have contributed so importantly to reaching this key milestone.”