FDA Approves Myqorzo, a New Oral Therapy for Obstructive Hypertrophic Cardiomyopathy

Myqorzo (aficamten) is a new oral medicine approved by the FDA for adults with symptomatic obstructive hypertrophic cardiomyopathy (oHCM). It relieves symptoms, improves heart function, and provides better stamina for daily activities.

Hypertrophic cardiomyopathy (HCM) is the most common inherited heart condition that causes the heart muscle to thicken, which can impair blood flow, making it harder for your heart to pump properly. More than 300,000 people in the U.S. are affected by HCM, but many more – possibly up to 800,000 – may not know they have it. About half of all people with HCM have the obstructive form that can cause symptoms such as shortness of breath, tiredness, and chest pain, making daily life difficult. People affected by HCM are also at a higher risk of having serious heart problems such as an irregular heartbeat, stroke, or valve disease – and in severe cases, their condition can progress to heart failure, requiring a transplant.

Myqorzo works by targeting a protein in the heart called myosin that helps the heart contract. By reducing the number of active myosin proteins, Myqorzo controls how strongly the heart squeezes, helping it reduce blockage and improve blood flow.

This approval matters because until now, treatment options have been limited, and many people continued to have symptoms even with current therapies. Myqorzo offers a new way to manage oHCM by directly targeting the cause of the blockage.

Why Was It Approved?

The FDA approved Myqorzo because clinical studies showed that it was well tolerated, helped people with oHCM feel better, and was equally effective across all subgroups, regardless of age, gender, health status, or other medications such as beta-blockers. In the study, people who took Myqorzo showed a significant improvement in how much oxygen their body used during exercise compared with those who took a placebo. This means they were able to be more physically active and had fewer symptoms.

In a phase III clinical trial, 282 adults with symptomatic oHCM were treated for 24 weeks with either Myqorzo or a placebo. After 24 weeks, patients taking Myqorzo showed a clear improvement in exercise capacity, with peak oxygen uptake increasing by 1.8 mL/kg/min, compared to those receiving the placebo showing no changes. Myqorzo also led to significant improvements across all 10 key secondary parameters, including symptoms, quality of life scores, heart pressure gradients, and functional status, compared with the placebo.

Side effects happened at similar rates in both groups, suggesting the treatment was generally well tolerated. The most common side effect was high blood pressure. A small number of people had a temporary drop in how well their heart pumped blood, but this did not lead to heart failure or stopping the medicine. However, Myqorzo can cause serious side effects, including heart failure, a condition in which the heart is unable to pump with enough force.

What Do I Need to Know?

You take Myqorzo by mouth once daily, around the same time, with or without food. Your health care provider will choose your starting dose and may adjust it based on your heart function. If you miss a dose, take it as soon as you remember, then take your next dose at the usual time the next day. Don’t take two doses in one day.

The medicine has a boxed warning about a risk of heart failure, as it can lower how well the heart pumps blood. Because of this risk, heart tests (echocardiograms) are needed before starting the drug and during treatment to monitor heart function. Myqorzo should not be started in patients whose heart-pumping function, measured as left ventricular ejection fraction (LVEF), is below 55%.

Because Myqorzo can affect how strongly your heart pumps, it’s only available through a special safety program called the Myqorzo Risk Evaluation and Mitigation Strategy. To get the medicine, both you and your health care provider must enroll in this program. Only certified pharmacies can give out Myqorzo, and it can only be sent to people who are approved through the program. This helps make sure the medicine is used safely and that your heart is closely monitored.

You should not take Myqorzo if you are also taking rifampin, an antibiotic medicine that can make Myqorzo less effective. Other medicines, such as fluconazole, fluvoxamine, and voriconazole, may raise the amount of Myqorzo in your body and increase the risk of side effects. Always tell your health care provider about your medical history and all the medicines you take, including over-the-counter drugs, herbal remedies, vitamins, and health supplements.

Be sure to tell your health care provider if you are pregnant, planning to become pregnant, or become pregnant during treatment or within three weeks after your last dose, as it is not known whether the medicine could harm a fetus. Also tell them if you are breastfeeding or plan to breastfeed because it is not known if Myqorzo passes into breast milk, and your provider can help you decide the safest way to feed your baby during treatment.

You must inform your health care provider at once if you get very sick during the treatment, such as with a severe infection, or if you have new or worsening irregular heartbeats, as this could raise your risk of heart failure.

Contact your health care provider at once if you notice swelling in your legs, rapid weight gain, or if you have a racing sensation in your heart (palpitations), tiredness, or chest pain. These might be signs of serious side effects. Myqorzo is expected to be available in the U.S. in the second half of January 2026.