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EXPLORER-HCM Primary Composite Functional Endpoint

For patients with NYHA class II–III obstructive HCM,

CAMZYOS® Demonstrated
in the
Composite Functional Endpoint
vs Placebo1,2

Primary composite functional endpoint: proportion of patients with decreased symptom burden and increased functional capacity at week 301,2

The primary composite functional endpoint was defined as achieved with an improvement of pVO2 by 1.5 mL/kg/min or more and improvement in NYHA class by at least 1 or an improvement of pVO2 by 3.0 mL/kg/min or more and no worsening in NYHA class.1

Treatment difference (95% CI): 19% (9, 30); P=0.0005
Primary Endpoint CAMZYOS® (mavacamten) vs Placebo, Chart Primary Endpoint CAMZYOS® (mavacamten) vs Placebo, Chart

CI=confidence interval; pVO2=peak oxygen consumption.

The efficacy of CAMZYOS was evaluated in EXPLORER-HCM, a phase 3, double-blind, randomized, placebo-controlled trial that enrolled 251 adult patients with symptomatic (New York Heart Association [NYHA] class II and III) obstructive HCM, with left ventricular outflow tract (LVOT) peak gradient ≥50 mmHg, and left ventricle ejection fraction (LVEF) ≥55% at rest or with provocation.1 Patients were randomized in a 1:1 ratio to receive CAMZYOS (n=123) or placebo (n=128) once daily for 30 weeks.1

All subjects were initiated on CAMZYOS 5 mg (or matching placebo) once daily, and the dose was periodically adjusted to optimize patient response (decrease in LVOT gradient with Valsalva maneuver), maintain LVEF ≥50%, and was further informed by plasma concentrations of CAMZYOS.1,2

Select Important Safety Information

In the EXPLORER-HCM trial, adverse reactions occurring in >5% of patients and more commonly in the CAMZYOS group than in the placebo group were dizziness (27% vs 18%) and syncope (6% vs 2%). There were no new adverse reactions identified in VALOR-HCM.
Effects on Systolic Function
In the EXPLORER-HCM trial, mean (SD) resting LVEF was 74% (6) at baseline in both treatment groups. Mean (SD) absolute change from baseline in LVEF was -4% (8) in the CAMZYOS group and 0% (7) in the placebo group over the 30-week treatment period. At Week 38, following an 8-week interruption of trial drug, mean LVEF was similar to baseline for both treatment groups. In the EXPLORER-HCM trial, 7 (6%) patients in the CAMZYOS group and 2 (2%) patients in the placebo group experienced reversible reductions in LVEF <50% (median 48%: range 35-49%) while on treatment. In all 7 patients treated with CAMZYOS, LVEF recovered following interruption of CAMZYOS.

Please see additional Important Safety Information below, including Boxed WARNING.

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  1. CAMZYOS [package insert]. Princeton, NJ: Bristol-Myers Squibb Company; 2023.
  2. Olivotto I, Oreziak A, Barriales-Villa R, et al; EXPLORER-HCM study investigators. Mavacamten for treatment of symptomatic obstructive hypertrophic cardiomyopathy (EXPLORER-HCM): a randomised, double-blind, placebo-controlled, phase 3 trial. Lancet.