FDA Approves Aficamten (Myqorzo) for Symptomatic Obstructive Hypertrophic Cardiomyopathy

The US Food and Drug Administration has approved Cytokinetics’ aficamten (Myqorzo) 5 mg, 10 mg, 15 mg, 20 mg tablets for the treatment of adults with symptomatic obstructive hypertrophic cardiomyopathy (oHCM) to improve functional capacity and symptoms.1

According to a December 19, 2025, press release from the Company, the approval is based on positive results from the phase 3 SEQUOIA-HCM clinical trial demonstrating robust efficacy, safety, and clinically meaningful benefits across symptoms, exercise capacity, hemodynamics, and biomarker endpoints. Of note, the full US Prescribing Information for aficamten includes a Boxed Warning for the risk of heart failure.1

“HCM is a heart muscle disease associated with a significant symptom burden. This approval of a new drug, [aficamten], represents a meaningful addition to the treatment options available for symptomatic obstructive HCM patients,” Martin Maron, MD, Director, Hypertrophic Cardiomyopathy Center, Lahey Hospital and Medical Center, and Principal Investigator of SEQUOIA-HCM, said in a statement.1 “In SEQUOIA-HCM, [aficamten] improved exercise capacity and reduced symptoms while also being well-tolerated. For these reasons, [aficamten] represents an important step forward in how we care for people living with obstructive HCM.”

Aficamten is an allosteric and reversible inhibitor of cardiac myosin motor activity. In patients with oHCM, myosin inhibition with aficamten reduces cardiac contractility and left ventricular outflow tract (LVOT) obstruction.`

Results from SEQUOIA-HCM showed treatment with aficamten for 24 weeks significantly improved exercise capacity compared to placebo, increasing peak oxygen uptake (pVO2) measured by cardiopulmonary exercise testing (CPET) by 1.8 mL/kg/min compared to baseline in patients treated with aficamten versus 0.0 mL/kg/min in patients treated with placebo (least square mean (LSM) difference, 1.74 mL/kg/min; 95% CI, 1.04-2.44]; P = .000002). The treatment effect of aficamten was consistent across all prespecified subgroups, including age, sex, patient baseline characteristics, and in patients receiving or not receiving background beta-blocker therapy.1,2

In the trial, aficamten was well-tolerated with no instances of worsening heart failure or treatment interruptions due to low LVEF. Treatment emergent serious adverse events occurred in 5.6% of patients on aficamten and 9.3% of patients on placebo.1

Core laboratory echocardiographic LVEF was observed to be <50% in 5 patients (3.5%) on aficamten compared to 1 patient (0.7%) on placebo. Hypertension (8% vs 2%) was the only adverse reaction occurring in >5% of patients and more commonly on aficamten than on placebo. Aficamten-associated increases in blood pressure are consistent with relief of LVOT obstruction and improved cardiac output.1

As described in the press release, aficamten includes a Boxed Warning for the risk of heart failure. Cytokinetics notes aficamten reduces LVEF and can cause heart failure due to systolic dysfunction. Therefore, echocardiogram assessments are required prior to and during treatment with aficamten to monitor for systolic dysfunction, and initiation of aficamten in patients LVEF <55% is not recommended.1

The release instructs providers to decrease the dose of aficamten if LVEF <50% and ≥40% and to interrupt the dose of aficamten if LVEF <40% or if the patient experiences heart failure symptoms or worsening clinical status due to systolic dysfunction. Because of the risk of heart failure due to systolic dysfunction, aficamten is available only through a restricted program under a Risk Evaluation and Mitigation Strategy (REMS) called the MYQORZO REMS Program.1

“Living with symptomatic obstructive HCM means managing physical limitations and burdensome symptoms every day of your life,” said Lisa Salberg, Founder and CEO of the Hypertrophic Cardiomyopathy Association.1 “For far too long, we’ve had few options to address our needs, and the approval of [aficamten] is a long-awaited and major addition to bring new hope to patients living with oHCM. We are so grateful to the team at Cytokinetics for listening to the patient community and working in true partnership to bring this therapy to so many in need.”

References

1. Cytokinetics. Cytokinetics Announces FDA Approval of MYQORZO™ (aficamten) for the Treatment of Adults with Symptomatic Obstructive Hypertrophic Cardiomyopathy to Improve Functional Capacity and Symptoms. December 19, 2025. Accessed December 19, 2025. https://ir.cytokinetics.com/press-releases/press-release-details/2025/Cytokinetics-Announces-FDA-Approval-of-MYQORZO-aficamten-for-the-Treatment-of-Adults-with-Symptomatic-Obstructive-Hypertrophic-Cardiomyopathy-to-Improve-Functional-Capacity-and-Symptoms/default.aspx

2. Campbell P. Aficamten Showcases oHCM Benefit in Phase 3 SEQUOIA-HCM Trial. HCPLive. May 13, 2024. Accessed December 19, 2025. https://www.hcplive.com/view/aficamten-showcases-ohcm-benefit-in-phase-3-sequoia-hcm-trial