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Clinical Study to Evaluate Mavacamten (MYK-461) in Adults With Symptomatic Obstructive Hypertrophic Cardiomyopathy

Phase 3
Completed
Conditions
Obstructive Hypertrophic Cardiomyopathy
Interventions
Drug: Placebo
Drug: mavacamten
Registration Number
NCT03470545
Lead Sponsor
MyoKardia, Inc.
Brief Summary

This is a multicenter, international, double-blind study of the administration of mavacamten in participants with symptomatic obstructive HCM (oHCM). Approximately 220 participants will be randomized to receive placebo or mavacamten.

Detailed Description

Not available

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
251
Inclusion Criteria
  • Age 18 and greater, body weight ≥ 45kg
  • Has adequate acoustic windows to enable accurate transthoracic echocardiograms (TTEs)
  • Diagnosed with oHCM consistent with current American College of Cardiology Foundation/American Heart Association and European Society of Cardiology guidelines and satisfy both criteria:
  • Has documented left ventricular ejection fraction (LVEF) ≥55%
  • NYHA Class II or III
  • Has documented oxygen saturation at rest ≥90% at Screening
  • Is able to perform an upright CPET and has a respiratory exchange ratio (RER) ≥1.0 at Screening per central reading

Key

Read More
Exclusion Criteria
  • Known infiltrative or storage disorder causing cardiac hypertrophy that mimics oHCM, such as Fabry disease, amyloidosis, or Noonan syndrome with LV hypertrophy
  • History of syncope or sustained ventricular tachyarrhythmia with exercise within 6 months prior to Screening
  • History of resuscitated sudden cardiac arrest (at any time) or known history of appropriate implantable cardioverter defibrillator (ICD) discharge for life-threatening ventricular arrhythmia within 6 months prior to Screening
  • Paroxysmal, intermittent atrial fibrillation with atrial fibrillation present at Screening
  • Persistent or permanent atrial fibrillation not on anticoagulation for at least 4 weeks prior to Screening and/or not adequately rate controlled within 6 months prior to Screening
  • Treatment (within 14 days prior to Screening) or planned treatment during the study with disopyramide or ranolazine
  • Treatment (within 14 days prior to Screening) or planned treatment during the study with a combination of β-blockers and calcium channel blockers
  • LVOT gradient with Valsalva maneuver <30 mmHg at Screening
  • Has been successfully treated with invasive septal reduction (surgical myectomy or percutaneous alcohol septal ablation [ASA]) within 6 months prior to Screening or plans to have either of these treatments during the study
  • ICD placement within 2 months prior to Screening or planned ICD placement during the study
  • Has a history or evidence of any other clinically significant disorder, condition, or disease that, in the opinion of the investigator, would pose a risk to participant safety or interfere with the study evaluation, procedures, or completion
  • Prior treatment with cardiotoxic agents such as doxorubicin or similar
Read More

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
PlaceboPlacebo-
mavacamten (MYK-461)mavacamten-
Primary Outcome Measures
NameTimeMethod
Percentage of Participants Achieving A Clinical Response30 weeks

A positive clinical response (value="YES") is defined as having achieved either an improvement of at least 1.5 mL/kg/min in peak oxygen consumption (pVO2) as determined by cardiopulmonary exercise testing (CPET) and a reduction of one or more class in New York Heart Association (NYHA) functional classification (e.g.I, II, III, or IV) -OR- an improvement of 3.0 mL/kg/min or more in pVO2 with no worsening in NYHA Functional Class.

Secondary Outcome Measures
NameTimeMethod
Changes From Baseline to Week 30 in Post Exercise in LVOT Peak Gradient.30 weeks

The post-exercise LVOT gradient was measured from echocardiograms obtained at baseline and week 30 following a study-specified exercise protocol and read by the Cardiovascular Imaging Core Laboratory (CICL, Boston MA). Change from baseline was determined as per the study statistical analysis plan and compared between treatment arms.

Change From Baseline to Week 30 in pVO2 as Assessed by CPET30 weeks

Cardiopulmonary exercise testing (CPET) was performed at baseline and week 30 following a study-specified protocol and peak oxygen consumption (pVO2) was determined by the Cardiovascular Metabolic Disease Research Institute (CMDRI, Palo Alto, CA). Change from baseline was determined as per the study statistical analysis plan and compared between treatment arms.

Proportion of Participants With at Least 1 Class Improvement in NYHA Functional Class From Baseline to Week 3030 weeks

New York Heart Association (NYHA) functional classification was determined by the principal investigator at baseline and at specified timepoints in the study. At baseline, all subjects were NYHA Class II or III. For the secondary outcome, NYHA class at Week 30 was compared to baseline and the proportion of subjects with an improvement of at least one class was determined, and the difference between treatment groups was analyzed. The proportion was also multiplied by 100 to provide the result as a percent.

Change From Baseline to Week 30 in Participant-reported Health-related Quality of Life as Assessed by the KCCQ Score30 weeks

The Kansas City Cardiomyopathy Questionnaire (KCCQ) is a patient reported outcome instrument with minimum score = 0 and maximum score = 100 where higher score indicates better health status. There are no units to the score. The instrument utilizes a recall period of 2 weeks over which patients describe the frequency and severity of their symptoms, their physical and social limitations, and how they perceive their heart failure symptoms to affect their quality of life. The KCCQ clinical summary (KCCQ-CS) score, a prespecified secondary outcome of EXPLORER-HCM, combines the physical limitation and total symptom scores.

Change From Baseline to Week 30 in Participant-reported Severity of HCM Symptoms as Assessed by the HCMSQ Score30 weeks

The Hypertrophic Cardiomyopathy Symptom Questionnaire (HCMSQ) is a patient reported outcome instrument that is a daily self-administered 11-item questionnaire. The HCMSQ assesses the core symptoms of HCM (tiredness/fatigue, heart palpitations, chest pain, dizziness, and shortness of breath). The Shortness of Breath domain score, a pre-specified secondary outcome of EXPLORER-HCM, assesses the frequency and severity of shortness of breath. The minimum score = 0 and maximum score = 18 where lower score indicates better health status. There are no units to the score.

Trial Locations

Locations (71)

Cedars-Sinai Medical Center (Smidt Heart Institute)

🇺🇸

Los Angeles, California, United States

Northwestern University

🇺🇸

Chicago, Illinois, United States

Houston Methodist Hospital

🇺🇸

Houston, Texas, United States

University of Texas Houston Medical School

🇺🇸

Houston, Texas, United States

University of Washington Medical Center

🇺🇸

Seattle, Washington, United States

UCSF School of Medicine

🇺🇸

San Francisco, California, United States

Duke Cardiology at Southpoint

🇺🇸

Durham, North Carolina, United States

Cincinnati Children's Hospital Medical Center

🇺🇸

Cincinnati, Ohio, United States

Intermountain Medical Center

🇺🇸

Salt Lake City, Utah, United States

University of Utah

🇺🇸

Salt Lake City, Utah, United States

Oregon Health & Science University

🇺🇸

Portland, Oregon, United States

Spectrum Health

🇺🇸

Grand Rapids, Michigan, United States

Mayo Clinic Jacksonville - PPDS

🇺🇸

Jacksonville, Florida, United States

Charité Campus Buch - Experimental and Clinical Research Center

🇩🇪

Berlin, Germany

UZ Antwerpen

🇧🇪

Edegem, Antwerpen, Belgium

University Clinic Heidelberg - PPDS

🇩🇪

Heidelberg, Germany

Vseobecna fakultni nemocnice v Praze

🇨🇿

Praha 2, Czechia

University of Michigan

🇺🇸

Ann Arbor, Michigan, United States

University Of Iowa Hospitals And Clinics

🇺🇸

Iowa City, Iowa, United States

St. Luke's Cardiology Associates

🇺🇸

Bethlehem, Pennsylvania, United States

University of Virginia Health System

🇺🇸

Charlottesville, Virginia, United States

University of Texas Southwestern Medical Center

🇺🇸

Dallas, Texas, United States

Carolinas Medical Center

🇺🇸

Charlotte, North Carolina, United States

Barzilai Medical Center

🇮🇱

Ashkelon, Israel

Hôpital de Rangueil

🇫🇷

Toulouse, France

St Bartholomew's Hospital

🇬🇧

London, United Kingdom

Onze-Lieve-Vrouwziekenhuis

🇧🇪

Aalst, Oost-Vlaanderen, Belgium

ZIV Medical Center

🇮🇱

Safed, Israel

Kerckhoff-Klinik-Forschungs-GmbH

🇩🇪

Bad Nauheim, Germany

Hospital da Luz

🇵🇹

Lisboa, Portugal

Odense Universitetshospital

🇩🇰

Odense, Denmark

Cardiologicum Dresden und Pirna

🇩🇪

Dresden, Germany

Institut Klinicke a Experimentalni Mediciny

🇨🇿

Prague, Czechia

Tel Aviv Sourasky Medical Center

🇮🇱

Tel Aviv, Tel-Aviv, Israel

University Medicine Göttingen

🇩🇪

Göttingen, Neidersachsen, Germany

Hospital Universitario Ramon y Cajal

🇪🇸

Madrid, Spain

Erasmus MC

🇳🇱

Rotterdam, Zuid-Holland, Netherlands

Kardio Klinika Brynów

🇵🇱

Katowice, Slaskie, Poland

University Hospital of Wales

🇬🇧

Cardiff, South Glamergon, United Kingdom

Hospital Universitario A Coruña

🇪🇸

La Coruña, Spain

Hospital Universitario Virgen Macarena

🇪🇸

Sevilla, Spain

Aarhus Universitetshospital

🇩🇰

Aarhus N, Denmark

Bispebjerg Hospital

🇩🇰

København NV, Denmark

Azienda Ospedaliera Universitaria Careggi

🇮🇹

Firenze, Italy

CHRU Nantes

🇫🇷

Nantes, Loire-Atlantique, France

Maastricht University Medical Center

🇳🇱

Maastricht, Limburg, Netherlands

Hôpital Erasme

🇧🇪

Brussels, Belgium

Collegium Medicum Uniwersytetu Jagiellonskiego

🇵🇱

Kraków, Malopolskie, Poland

Instytut Kardiologii im Prymasa Tysiaclecia Kardynala Stefana Wyszynskiego

🇵🇱

Warsaw, Poland

Hospital Garcia de Orta

🇵🇹

Almada, Portugal

Hospital Universitario Virgen de La Arrixaca

🇪🇸

El Palmar, Murcia, Spain

Szpital Kliniczny Przemienienia Panskiego Uniwesytetu Medycznego im. Karola Marcinkowskiego

🇵🇱

Poznań, Poland

Rabin Medical Center - PPDS

🇮🇱

Petach Tikva, Israel

Columbia University Medical Center

🇺🇸

New York, New York, United States

Kaplan Medical Center

🇮🇱

Reẖovot, Israel

Brigham and Women's Hospital

🇺🇸

Boston, Massachusetts, United States

Methodist University Hospital

🇺🇸

Memphis, Tennessee, United States

Groupe Hospitalier Pitié Salpétrière

🇫🇷

Paris, France

Hospital Universitario Puerta de Hierro - Majadahonda

🇪🇸

Madrid, Spain

Yale New Haven Hospital

🇺🇸

New Haven, Connecticut, United States

Stanford University

🇺🇸

Stanford, California, United States

NYU Langone Medical Center

🇺🇸

New York, New York, United States

University of Pennsylvania (Penn Heart and Vascular Center)

🇺🇸

Philadelphia, Pennsylvania, United States

University of Pittsburgh Medical Center Presbyterian

🇺🇸

Pittsburgh, Pennsylvania, United States

Hôpital Européen Georges Pompidou

🇫🇷

Paris, France

Charité - Universitätsmedizin Berlin

🇩🇪

Berlin, Germany

Universitatsklinikum Schleswig-Holstein

🇩🇪

Kiel, Germany

Hadassah Medical Center PPDS -

🇮🇱

Jerusalem, Israel

The Chaim Sheba Medical Center - The Edmond and Lily Safra Children's Hospital

🇮🇱

Ramat-Gan, Israel

Washington University School of Medicine

🇺🇸

Saint Louis, Missouri, United States

Mayo Clinic Arizona

🇺🇸

Scottsdale, Arizona, United States

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