Aficamten
MYQORZO
What it isCardiac myosin inhibitor reducing hypercontractility; symptomatic obstructive hypertrophic cardiomyopathy.
Why this oneIts shorter action than mavacamten permits faster adjustment and quicker recovery if systolic function falls.
What limits itSystolic dysfunction requires echocardiographic monitoring under a REMS; strong CYP inducers are contraindicated.
FDA-approved for
- obstructive hypertrophic cardiomyopathy (2025)
FDA label
Read the full label on DailyMed ↗
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Obstructive hypertrophic cardiomyopathy (oHCM) | Adults | 5 mg QD | Individualized 5–20 mg QD by LVEF and Valsalva LVOT-G (Table 1) | 20 mg QD |
Titration Increase by 5 mg every 2–8 weeks (echo-guided) until maintenance or 20 mg QD; do not up-titrate if LVEF <55%; after interruption for low LVEF, resume no earlier than 7 days once LVEF ≥55%, restarting at 5 mg
Renal No clinically meaningful PK differences in mild–moderate impairment (eGFR ≥30 mL/min); severe (eGFR <30) unknown
Hepatic No clinically meaningful PK differences in mild–moderate impairment (Child-Pugh A/B); severe (Child-Pugh C) unknown
Do not take two doses on the same day; restricted distribution via MYQORZO REMS
Instructions
- Take QD at about the same time each day, with or without food; swallow tablets whole
- Missed dose: take same day if possible; never two doses in one day
- Echo (LVEF + Valsalva LVOT-G) 2–8 weeks after initiation or any dose change; at maintenance q6 months (q3 months if LVEF 50–<55%)
- LVEF 40–<50%: step dose down (20→15, 15→10, 10→5 mg); if on 5 mg, interrupt ≥7 days. LVEF <40% or heart-failure symptoms: interrupt ≥7 days
- Reduce dose when initiating fluconazole/voriconazole, fluvoxamine, or a strong CYP2C9 inhibitor, or when discontinuing a moderate–strong CYP3A inducer (per label steps); avoid fluconazole/voriconazole if on 5 or 10 mg
- Hold up-titration during intercurrent illness (e.g., severe infection) or new/uncontrolled arrhythmia until resolved
Contraindications
- Concomitant rifampin (reduces aficamten exposure; loss of effectiveness)
Cautions
- Heart failure due to systolic dysfunction — reduces contractility/LVEF; assess clinical status and LVEF before and regularly during treatment; risk higher with serious intercurrent illness or arrhythmia
- Do not initiate if LVEF <55%
- MYQORZO REMS Program — certified prescribers/pharmacies, enrolled patients with ongoing monitoring
- CYP interactions: multi-CYP inhibitors (fluconazole, voriconazole, fluvoxamine), strong CYP2C9 inhibitors, or stopping CYP3A inducers raise levels (heart-failure risk); CYP inducers lower levels (loss of effectiveness)
Adverse reactions
- Hypertension (8% vs 2% placebo; only reaction >5%)
- LVEF reduction (mean −7%; reversible LVEF <50% in 4%)
- Heart failure (see Warnings)
Pregnancy No human data; structural malformations in rats at ≥4x MRHD exposure; oHCM itself increases preterm-birth risk — pregnancy safety study, report exposures to Cytokinetics
Lactation No human data; detected in rat milk (likely present in human milk) — weigh benefits of breastfeeding against maternal need and infant risk
NO BOXED WARNINGS
Principal riskSystolic dysfunction; echo monitoring required
Classes and tags
Clinical profile
Mechanism of action: Aficamten ballicule
