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A study to evaluate the safety and benefit of Mavacamten (MYK-461) in adults with an inherited heart disease causing thickening of the heart muscle

A Randomized, Double blind, Placebo controlled Clinical Study to Evaluate Mavacamten (MYK-461) in Adults with Symptomatic Obstructive Hypertrophic Cardiomyopathy - EXPLORER-HCM

Status
Active, not recruiting
Phases
Phase 3
Study type
Interventional
Source
EU CTR
Registry ID
EUCTR2017-002530-23-ES
Enrollment
220
Registered
2018-06-12
Start date
2018-09-19
Completion date
Unknown
Last updated
2021-10-08

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Hypertrophic Cardiomyopathy MedDRA version: 20.0 Level: PT Classification code 10020871 Term: Hypertrophic cardiomyopathy System Organ Class: 10010331 - Congenital, familial and genetic disorders

Interventions

Sponsors

MyoKardia, Inc.
Lead Sponsor

Eligibility

Sex/Gender
All

Inclusion criteria

Inclusion criteria: 1.Able to understand and comply with the study procedures, understand the risks involved in the study, and provide written informed consent according to federal, local, and institutional guidelines before the first study specific procedure 2.Is at least 18 years old at Screening 3.Body weight is greater than 45 kg at Screening 4.Has adequate acoustic windows to enable accurate TTEs 5.Diagnosed with oHCM consistent with current American College of Cardiology Foundation/American Heart Association and European Society of Cardiology guidelines, ie, satisfy both criteria below (criteria to be documented by the echocardiography core laboratory): A.Has unexplained left ventricular (LV) hypertrophy with nondilated ventricular chambers in the absence of other cardiac (eg, hypertension, aortic stenosis) or systemic disease and with maximal LV wall thickness =15 mm (or =13 mm with positive family history of hypertrophic cardiomyopathy [HCM]), and B.Has LVOT peak gradient =50 mmHg during Screening as assessed by echocardiography at rest, after Valsalva maneuver, or postexercise (confirmed by echocardiography core laboratory interpretation) 6.Has documented left ventricular ejection fraction (LVEF) =55% by echocardiography core laboratory read of Screening TTE 7.Has New York Heart Association (NYHA) Class II or III symptoms at Screening 8.Has documented oxygen saturation at rest =90% at Screening 9.Is able to perform an upright CPET and has a respiratory exchange ratio (RER) =1.0 at Screening per central reading; if the RER is between 0.91 and 1.0, the participant may be enrolled only if it is determined by the central CPET laboratory that peak exercise has been achieved in the subject (the only permitted reasons for subpeak performance are [1] a decrease in systolic blood pressure or [2] severe angina as described in the CPET Laboratory Manual) 10.Female participants must not be pregnant or lactating and, if sexually active, must be using one of the following acceptable birth control methods from the Screening visit through 3 months after the last dose of investigational medicinal product (IMP). Hormonal contraceptives are not considered highly effective contraception for this study because mavacamten could reduce the effectiveness of hormonal contraceptives. •Double barrier method (eg, vasectomy or male using a condom and female using a diaphragm or cervical cap) •Barrier (eg, male using a condom) plus female uses non hormonal intrauterine device or intrauterine system •Female is surgically sterile for 6 months or postmenopausal for 2 years. Permanent sterilization includes hysterectomy, bilateral oophorectomy, bilateral salpingectomy, and/or documented bilateral tubal occlusion at least 6 months prior to Screening. Females are considered postmenopausal if they have had amenorrhea for at least 2 years or more following cessation of all exogenous hormonal treatments and follicle stimulating hormone levels are in the postmenopausal range 11.Male participants with sexual partners must agree to use condoms for the duration of the study and for 3 months after the last dose of IMP in order to prevent passing mavacamten to the partner in the ejaculate Are the trial subjects under 18? no Number of subjects for this age range: F.1.2 Adults (18-64 years) yes F.1.2.1 Number of subjects for this age range 187 F.1.3 Elderly (>=65 years) yes F.1.3.1 Number of subjects for this age range 33

Exclusion criteria

Exclusion criteria: 1.Previously participated in a clinical study with mavacamten 2.Hypersensitivity to any of the components of the mavacamten formulation 3.Participated in a clinical trial in which the participant received any investigational drug (or is currently using an investigational device) within 30 days of Screening, or at least 5x the respective elimination half life (whichever is longer) 4.Infiltrative or storage disorder causing CH that mimics oHCM, such as Fabry disease, amyloidosis, or Noonan syndrome with LVH 5.Medical condition that precludes upright exercise stress testing 6.History of syncope or sustained VT with exercise within 6 months prior to Screening 7.History of resuscitated sudden CA (at any time) or history of appropriate ICD discharge for life-threatening VA within 6 months prior to Screening 8.Has paroxysmal, intermittent AF with AF present per the investigator’s evaluation of the participant’s ECG at time of Screening 9.Has persistent/permanent AF not on anticoagulation for at least 4 weeks to Screening &/or not adequately rate controlled within 6 months prior to Screening 10.Current treatment (within 14 days to Screening) or planned treatment during the study with disopyramide or ranolazine 11.Current treatment (within 14 days prior to Screening) or planned treatment during the study with a combination of ß-blockers and verapamil or a combination of ß-blockers and diltiazem 12.Individuals on ß-blockers, verapamil, or diltiazem, any dose adjustment of that medication 480 ms or other ECG abnormality considered by investigator to pose risk to participant safety (eg, second-degree atrioventricular block type II) 17.Documented OCAD (>70% stenosis in one or more epicardial coronary arteries) or history of MI 18.Moderate or severe (as per investigator’s judgment) AVS at Screening 19.Acute or serious comorbid condition (eg, major infection or hematologic, renal, metabolic, gastrointestinal, or endocrine dysfunction) that, in the judgment of the investigator, could lead to premature termination of study participation or interfere with the measurement or interpretation of the efficacy & safety assessments in the study 20.Has pulmonary disease that limits exercise capacity or systemic arterial oxygen saturation 21.History of clinically significant malignant disease within 10 years of Screening: •Who have been successfully treated for nonmetastatic cutaneous squamous cell or basal cell carcinoma or been adequately treated for cervical carcinoma in situ can be included in the study •With other malignancies who are cancer free for more than 10 years before Screening can be included in the study 22.Has safety laboratory parameters (chemistry, hematology, coagulation, & urinalysis) outside normal limits (according to the central laboratory reference range) at Screening as assessed by the central laboratory; however, participant with safety laboratory parameters outside normal limits may be included if he or she meets all of the f

Design outcomes

Primary

MeasureTime frame
Main Objective: To compare the effect of a 30-week course of mavacamten with placebo on clinical response comprising of exercise capacity and clinical symptoms in participants with symptomatic obstructive hypertrophic cardiomyopathy (oHCM);Secondary Objective: To compare the effect of a 30-week course of mavacamten with placebo on symptoms and left ventricular outflow tract (LVOT) obstruction as determined by Doppler echocardiography To compare the effect of a 30-week course of mavacamten with placebo on exercise capacity, clinical symptoms and Patient Reported Outcomes individually To assess the safety and tolerability of mavacamten To assess the pharmacokinetic (PK) characteristics of mavacamten;Primary end point(s): - Clinical response defined as achieving (1) an improvement of 1.5 mL/kg/min or more in peak oxygen consumption (pVO2) as determined by CPET, & (2) a reduction of one or more class in NYHA Functional Classification, at the end of Week 30 dosing period;Timepoint(s) of evaluation of this end point: Week 30

Secondary

MeasureTime frame
Timepoint(s) of evaluation of this end point: 1. Week 30 2. Week 30 3. Week 30 4. Week 30 5. Week 30 6. Week 30;Secondary end point(s): 1. Change from baseline to Week 30 in post-exercise LVOT peak gradient 2. Change from baseline to Week 30 in NYHA functional class 3. Change from baseline to Week 30 in peak oxygen consumption (pVO2) as determined by CPET 4. Proportion of participants achieving a post-exercise LVOT peak gradient <50 mmHg at Week 30 5. Proportion of participants achieving a post-exercise LVOT peak gradient <30 mmHg at Week 30 6. Change from baseline to Week 30 in patient-reported severity of HCM symptoms as assessed by the HCM Symptom Questionnaire score

Countries

Belgium, Czech Republic, Denmark, France, Germany, Israel, Italy, Netherlands, Poland, Portugal, Spain, United Kingdom, United States

Contacts

Public ContactClinical Trial or Medical Inquiries

MyoKardia, Inc.

RegistroEspanolDeEstudiosClinicos@druginfo.com900834223

Outcome results

None listed

Source: EU CTR (via WHO ICTRP) · Data processed: Feb 4, 2026