BOXED WARNING Risk of heart failure — reduces LVEF and can cause systolic dysfunction; echocardiographic LVEF assessment required before/during use; contraindicated with strong CYP2C19 inhibitors and moderate-to-strong CYP2C19/CYP3A4 inducers; available only via CAMZYOS REMS.
FDA dosing
Population
Start
Target
Max
Symptomatic obstructive HCM
Adult
5 mg QD
individualized 2.5–15 mg QD
15 mg QD
Obstructive HCM + moderate CYP2C19 or strong CYP3A4 inhibitor
Adult
2.5 mg QD
individualized
15 mg QD
Titration Assess LVEF and Valsalva LVOT gradient before each up-titration (weeks to steady state); when on an interacting inhibitor, do not up-titrate until 12 weeks after inhibitor initiation.
Renal Undefined
Hepatic No adjustment for mild–moderate (Child-Pugh A/B) with the standard titration/monitoring plan; severe (Child-Pugh C) unknown.
Available only through the CAMZYOS REMS Program.
Instructions
Swallow capsules whole; do not break, open, or chew.
Take once daily with or without food.
Confirm absence of pregnancy and use effective contraception before starting.
If a dose is missed, take when remembered; do not take two doses the same day.
Interrupt treatment if LVEF <50% or on worsening clinical status.
Available strengths
cap 2.5, 5, 10, 15 mg
Contraindications
Concomitant strong CYP2C19 inhibitors.
Concomitant moderate-to-strong CYP2C19 inducers or moderate-to-strong CYP3A4 inducers.
Cautions
Heart failure due to systolic dysfunction; higher risk with intercurrent illness or arrhythmia.
CYP2C19/CYP3A4 drug interactions leading to heart failure or loss of effectiveness.
Embryo-fetal toxicity; may reduce effectiveness of some hormonal contraceptives.
Avoid with disopyramide, ranolazine, or verapamil/diltiazem plus a beta blocker.
Adverse reactions
dizziness (27%)
syncope (6%)
Pregnancy May cause fetal harm (animal data); confirm absence of pregnancy before starting and use contraception during and 4 months after last dose.
Lactation No data on presence in milk or effects on infant/production; weigh benefits.
Cost
Mavacamten (CAMZYOS)
Strength
#/mo
generic $/mo
CostPlus
2.5 mg
cap
30 qd
not offered
5 mg
cap
30 qd
not offered
10 mg
cap
30 qd
not offered
15 mg
cap
30 qd
not offered
NADAC is a voluntary CMS survey of what retail community pharmacies pay for the drugs they stock. Mavacamten is dispensed outside retail pharmacies, so it rarely appears on surveyed invoices.
Legacy pregnancy categoryNot assigned — PLLR-era drug
Defining liabilityGenerally tolerated at therapeutic doses; clinically important risks are agent-specific and increase with interactions or organ impairment.