Camzyos Dosage

Initiation, Maintenance, and Interruption of Treatment

Confirm absence of pregnancy and usage of effective contraception in females of reproductive potential.

Initiation or up-titration of CAMZYOS in patients with LVEF <55% is not recommended.

The recommended starting dose is 5 mg orally once daily without regard to food; allowable subsequent doses with titration are 2.5 mg, 5 mg, 10 mg, or 15 mg orally once daily. The maximum recommended dose is 15 mg orally once daily.

Patients may develop heart failure while taking CAMZYOS. Regular LVEF and Valsalva left ventricular outflow tract (LVOT) gradient assessment is required for careful titration to achieve an appropriate target Valsalva LVOT gradient, while maintaining LVEF ≥50% and avoiding heart failure symptoms (see Figure 1 and Figure 2).

Daily dosing takes weeks to reach steady-state drug levels and therapeutic effects, and genetic variation in metabolism and drug interactions can cause large differences in exposure.

​When initiating or titrating CAMZYOS, first consider LVEF then consider the Valsalva LVOT gradient and patient clinical status to guide appropriate CAMZYOS dosing. Assessment of post-exercise LVOT gradient may be considered in symptomatic patients with normal or near normal Valsalva gradients (approximately 30 mmHg) prior to initiating treatment with CAMZYOS. Follow the algorithms for Initiation (Figure 1) and Maintenance (Figure 2) for appropriate CAMZYOS dosing and monitoring schedules.

If LVEF <50% while taking CAMZYOS, interrupt treatment. Follow the algorithm for Interruption (Figure 3) for guidance on interrupting, restarting, or discontinuing CAMZYOS. If interrupted at 2.5 mg, either restart at 2.5 mg or discontinue permanently.

Figure 1: Initiation Phase

Figure 2: Maintenance Phase

Figure 3: Treatment Interruption at Any Clinic Visit if LVEF <50%

Delay dose increases when there is intercurrent illness (e.g., serious infection) or arrhythmia (e.g., atrial fibrillation or other uncontrolled tachyarrhythmia) that may impair systolic function. Consider interruption of CAMZYOS in patients with intercurrent illness.

Missed or delayed doses

If a dose is missed, it should be taken as soon as possible, and the next scheduled dose should be taken at the usual time the following day. Exact timing of dosing during the day is not essential, but two doses should not be taken on the same day.

Swallow capsules whole. Do not break, open, or chew the capsules.

Concomitant Administration of Weak to Moderate CYP2C19 or Moderate to Strong CYP3A4 Inhibitors

Initiate CAMZYOS at the recommended starting dosage of 5 mg orally once daily in patients who are on stable therapy with a weak CYP2C19 inhibitor or a moderate CYP3A4 inhibitor (see Figure 1).

In patients who are on stable therapy with a moderate CYP2C19 inhibitor or a strong CYP3A4 inhibitor, initiate CAMZYOS at 2.5 mg orally once daily. Interrupt CAMZYOS treatment if Valsalva LVOT gradient is <20 mm Hg at Week 4 or Week 8. Treatment may be resumed after 4 weeks at 2.5 mg once daily if LVEF is ≥50%. If treatment is resumed at Week 12, recheck clinical status, Valsalva LVOT gradient and LVEF in 4 weeks, and maintain the current dose for the next 8 weeks unless LVEF is <50%.

In patients who initiate a weak to moderate CYP2C19 inhibitor or a moderate to strong CYP3A4 inhibitor, reduce dosage of CAMZYOS to the next lower daily (mg) dose level (i.e., 15 mg to 10 mg; 10 mg to 5 mg; or 5 mg to 2.5 mg). Schedule clinical and echocardiographic assessment 4 weeks after inhibitor initiation, and do not up-titrate to the next higher daily (mg) dose level of CAMZYOS until 12 weeks after inhibitor initiation. Avoid initiation of concomitant weak to moderate CYP2C19 and moderate to strong CYP3A4 inhibitors in patients who are on stable treatment with 2.5 mg of CAMZYOS because a lower CAMZYOS once-daily dose is not available.

For short-term use (e.g., 1 week), interrupt CAMZYOS for the duration of treatment with a weak to moderate inhibitor of CYP2C19 or a moderate to strong inhibitor of CYP3A4. Mavacamten may be reinitiated at the previous dose immediately on discontinuation of concomitant therapy.