Mavacamten(Camzyos)

Mavacamten is a novel prescription cardiac myosin inhibitor targeting the pathological mechanism of obstructive hypertrophic cardiomyopathy (HCM). On April 30, 2022, Bristol Myers Squibb announced that it had been approved by the U.S. Food and Drug Administration (FDA) for the treatment of adult patients with symptomatic obstructive hypertrophic cardiomyopathy (HCM) of New York Heart Association (NYHA) functional class II‑III to improve functional capacity and symptoms. Patients should strictly follow the doctor’s instructions.

Target of Action

Cardiac myosin

Dosage and Administration

Route and Frequency of Administration: Oral, once daily.

The dosage of mavacamten should be adjusted according to the patient’s actual condition. Patients must consult a physician and strictly follow medical advice.

Recommended Reading: Recommended Dosage and Dosage Adjustment of Mavacamten

Adverse Reactions

Major Risks and Warnings: Risk of heart failure, embryo-fetal toxicity.

Common side effects: Dizziness, syncope.

Serious side effects: Decreased left ventricular ejection fraction, symptoms of heart failure, other cardiovascular effects.

Reference Article: Serious and Common Side Effects of Mavacamten

Use in Special Populations

Pregnancy: Mavacamten may cause fetal harm when administered to pregnant women. Advise pregnant women of the potential risk to the fetus with maternal exposure to mavacamten during pregnancy.

Lactation: It is unknown whether mavacamten is present in human or animal milk, has effects on the breastfed infant, or affects milk production. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for mavacamten and any potential adverse effects on the breastfed child from mavacamten or from the underlying maternal condition.

Females and Males of Reproductive Potential:

Verify pregnancy status in females of reproductive potential prior to initiating mavacamten. Advise females of reproductive potential to use effective contraception during treatment with mavacamten and for 4 months after the last dose.

Combined hormonal contraceptives (CHCs) containing ethinyl estradiol and norethindrone may be co-administered with mavacamten. However, mavacamten may reduce the effectiveness of some other CHCs. If these CHCs are used, advise patients to add a non-hormonal contraceptive method (e.g., condoms) or use an alternative contraceptive method during co-administration and for 4 months after the last dose of mavacamten.

Daily Precautions

1. Before and during treatment with mavacamten, inform your healthcare provider about all medicines you take, including prescription drugs, over-the-counter medicines, vitamins, and herbal supplements.

2. Co-administration of mavacamten with certain medications or grapefruit juice may result in heart failure.

3. Specifically inform your doctor if you are taking over-the-counter medications including omeprazole, esomeprazole, or cimetidine; taking other medicines for your obstructive hypertrophic cardiomyopathy; or have developed an infection.

4. Do not stop taking or change the dosage of mavacamten, and do not start any new medicine without informing your healthcare provider.

FDA，2025.04