mavacamten
Camzyos
Pharmaceutical company: Bristol-Myers Squibb
Pharmacologic classification:Cardiac myosin inhibitor
Therapeutic classification:Heart failure drug
AVAILABLE FORMS
Capsules: 2.5 mg, 5 mg, 10 mg, 15 mg
INDICATIONS AND DOSAGES
Symptomatic New York Heart Association class II to III obstructive hypertrophic cardiomyopathy to improve functional capacity and symptoms
Adults: Initially, 5 mg PO daily. Dosage must be individualized based on clinical status and echocardiographic assessment of patient response. Subsequent doses after titration may be 2.5, 5, 10, or 15 mg once daily. See the manufacturer’s instructions for initiation and maintenance dose algorithms based on left ventricular ejection fraction (LVEF) and Valsalva left ventricular outflow tract assessments.
Adjust-a-dose: For patients who are on stable therapy with a weak CYP2C19 or moderate CYP3A4 inhibitor, initiate mavacamten therapy with 5 mg PO once daily. For patients who initiate a weak CYP2C19 or a moderate CYP3A4 inhibitor during mavacamten therapy, reduce mavacamten dose by one level (15 mg to 10 mg; 10 mg to 5 mg; or 5 mg to 2.5 mg). Avoid initiation of concomitant weak CYP2C19 or moderate CYP3A4 inhibitors in patients stable on mavacamten 2.5 mg daily because a lower mavacamten dose isn’t available.
CONTRAINDICATIONS AND CAUTIONS
- Contraindicated in patients hypersensitive to mavacamten or its components.
- Black Box Warning: This drug is contraindicated with concomitant use of moderate to strong CYP2C19 inhibitors, strong CYP3A4 inhibitors, moderate-to-strong CYP2C19 inducers, or moderate-to-strong CYP3A4 inducers.
- Black Box Warning: This drug can cause heart failure due to systolic dysfunction.
- Black Box Warning: Echocardiogram assessments of LVEF are required before and during use of mavacamten.
- Black Box Warning: Initiation in patients with LVEF less than 55% isn’t recommended. Interrupt therapy if LVEF drops below 50% or if there is a worsening of clinical status.
- Consider interruption of the drug in patients with intercurrent illness as an exacerbation of cardiac symptoms may result.
- This drug hasn’t been studied in pediatric patients.
- Use cautiously in older adults.
- Black Box Warning: Because of the risk of heart failure due to systolic dysfunction, mavacamten is available only through a restricted program under the Camzyos REMS program.
- Dialyzable drug: Unlikely.
- Overdose S&S: Vasovagal reaction, hypotension, asystole, systolic dysfunction symptoms (shortness of breath, edema, fatigue, dizziness, cough, or wheezing).
PREGNANCY-LACTATION-REPRODUCTION
- This drug may cause fetal toxicity based on animal studies.
- Females of reproductive potential must use effective contraception during therapy and for 4 months after the last dose.
- This drug may reduce the effectiveness of combined hormonal contraceptives (CHCs). If patient is on a CHC, use an alternative contraceptive method or add nonhormonal contraception.
- Report pregnancies to Bristol-Myers Squibb pregnancy outcomes study at 1-800-721-5072 or www.bms.com.
- It’s unknown if this drug is present in human milk. Consider the developmental and health benefits of breastfeeding with the mother’s clinical need for the drug and risks to the breastfed child from the drug or from the underlying maternal condition.
INTERACTIONS
Drug-drug. Cimetidine: May increase mavacamten level. Use together cautiously.
CYP2C8 (repaglinide), CYP2C9 (tolbutamide), CYP2C19 (omeprazole), and CYP3A4 (midazolam, repaglinide) substrates: May reduce levels of substrate drugs. Monitor levels of substrate drugs when decreased levels may reduce their activity.
Disopyramide, ranolazine, verapamil with a beta blocker, diltiazem with a beta blocker: Use with mavacamten hasn’t been studied. Avoid use together.
Disopyramide with verapamil or diltiazem: May cause left ventricular dysfunction and heart failure in patients with obstructive hypertrophic cardiomyopathy. Avoid use together.
Hormonal contraceptives (progestin, ethinyl estradiol): May decrease ethinyl estradiol and progestin levels leading to contraceptive failure or breakthrough bleeding. Use a contraceptive method not affected by CYP450 enzyme induction (intrauterine system) or add nonhormonal contraception (condoms) during concomitant use and for 4 months after its last dose.
Black Box Warning: Moderate to strong CYP2C19 or CYP3A4 inducers (rifampin):
May decrease mavacamten level and reduce efficacy. Concomitant use is contraindicated.
Black Box Warning: Moderate to strong CYP2C19 inhibitors: May increase mavacamten level and the risk of heart failure. Concomitant use contraindicated.
Negative inotropes (beta blockers, diltiazem, verapamil): May have additive effects. When concomitant use can’t be avoided, monitor LVEF closely when initiating or increasing the negative inotrope dose until stable doses and clinical response have been achieved.
Black Box Warning: Strong CYP3A4 inhibitors (ketoconazole): May increase mavacamten level and increase the risk of heart failure due to systolic dysfunction. Concomitant use contraindicated.
Weak CYP2C19 inhibitors (esomeprazole, omeprazole) or moderate CYP3A4 inhibitors (ciprofloxacin, cyclosporine): May increase mavacamten level. Adjust mavacamten dose.
Drug-herb. St. John’s wort: May decrease mavacamten level and efficacy. Don’t use together.
Drug-food. Grapefruit juice: May increase mavacamten level and increase drug adverse effects. Discourage use together.
ADVERSE REACTIONS
CNS: dizziness, syncope.
CV: Heart failure, LVEF reduction.
Reactions in bold italics are life-threatening.
Released: August 2022
Nursing Drug Handbook
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