Key Remaining Study in Registration Program for oHCM
Enables Assessment of Mavacamten’s Potential for Disease Modification
SOUTH SAN FRANCISCO, Calif., Oct. 24, 2018 (GLOBE NEWSWIRE) -- MyoKardia, Inc. (Nasdaq: MYOK), a clinical-stage
biopharmaceutical company pioneering precision medicine for the treatment of cardiovascular diseases, today announced that patient
dosing has begun in the MAVA Long-Term Extension (MAVA-LTE) clinical trial. The MAVA-LTE study will assess long-term safety of
mavacamten, as well as its effects on symptoms and echocardiographic measures of systolic and diastolic cardiac function in
patients with hypertrophic cardiomyopathy (HCM). MAVA-LTE will serve as the key remaining study in the registration program
for mavacamten in obstructive HCM (oHCM).
“The MAVA-LTE study is expected to be a critical component of mavacamten’s anticipated registration package, providing important
information regarding the long-term safety and efficacy of mavacamten in HCM,” said June Lee, M.D., MyoKardia’s Chief Operating
Officer and Chief Development Officer. “Several adverse clinical outcomes in HCM are associated with structural changes in
the heart, including elevated risk of heart failure, cardiac arrest and atrial fibrillation. By reducing the excessive
contractility that is the key driver of HCM, we believe mavacamten treatment may remodel the heart over time. The duration of
MAVA-LTE and the incorporation of a cardiac magnetic resonance imaging substudy into its protocol will allow us to investigate
potential structural improvements to the diseased HCM heart that occur with daily mavacamten treatment.”
Up to 280 patients who successfully complete either MyoKardia’s MAVERICK-HCM or EXPLORER-HCM clinical trials of mavacamten will
be eligible for enrollment into MAVA-LTE. Approximately 100 patients are expected to participate in a cardiac magnetic
resonance imaging substudy to assess the potential effects of mavacamten treatment on cardiac mass and structure. The
treatment period for patients in MAVA-LTE will be up to two years from the time of their enrollment and through the planned
registration filing with the U.S. Food and Drug Administration (FDA) for the potential regulatory approval of mavacamten.
Data from the MAVA-LTE clinical trial, along with results of the EXPLORER-HCM trial, are intended to support the registration
submission of mavacamten for the treatment of oHCM.
All patients in MAVA-LTE will receive mavacamten in line with the active cohort protocol from their respective study. Study
participants’ treatment status (active or placebo) from MAVERICK-HCM or EXPLORER-HCM will remain blinded. Patients in
MAVA-LTE may maintain pre-existing background medications for HCM, such as beta blockers or calcium channel blockers throughout the
course of the trial.
About Mavacamten (MYK-461)
Mavacamten is a novel, oral, allosteric modulator of cardiac myosin being developed for the treatment of hypertrophic
cardiomyopathy (HCM). MyoKardia has advanced mavacamten into a pivotal Phase 3 clinical trial, known as the EXPLORER-HCM
study, in patients with symptomatic, obstructive HCM and a Phase 2 clinical trial, the MAVERICK-HCM study, in patients with
symptomatic non-obstructive HCM. Mavacamten is intended to reduce cardiac muscle contractility by inhibiting the excessive
myosin-actin cross-bridge formation that underlies the excessive contractility, left ventricular hypertrophy and reduced compliance
characteristic of HCM. In April 2016, the U.S. FDA granted Orphan Drug Designation for mavacamten for the treatment of
symptomatic oHCM, a subset of HCM. Mavacamten is being developed in an ongoing collaboration between MyoKardia and
Sanofi.
About Hypertrophic Cardiomyopathy
Hypertrophic cardiomyopathy (HCM) is the most common genetic cause of heart disease, in which the walls of the heart thicken and
prevent the left ventricle from expanding, resulting in a reduced pumping capacity. HCM is a chronic, progressive disease
that can be extremely disabling. According to recent research published in the journal Circulation(1),
HCM patients are at substantially elevated risks of long-term complications and comorbidities, such as atrial fibrillation and
heart failure. HCM patients also have significantly higher mortality rates compared to that of the general U.S.
population.
In approximately two-thirds of HCM patients, or an estimated 410,000 people in the U.S., the path followed by blood exiting the
heart, known as the left ventricular outflow tract (LVOT), becomes obstructed by the enlarged and diseased muscle, restricting the
flow of blood from the heart to the rest of the body. Mild exertion can quickly result in fatigue or shortness of breath, and
a patient’s ability to participate in normal work, family or recreational activities can be substantially curtailed.
Approximately one-third of patients, or 220,000 people in the U.S., have non-obstructive HCM. As nHCM progresses,
symptoms begin to resemble those of a congestive heart failure patient and heart transplantation may become the only viable
treatment option.
About MyoKardia
MyoKardia is a clinical-stage biopharmaceutical company pioneering a precision medicine approach to discover, develop and
commercialize targeted therapies for the treatment of serious and rare cardiovascular diseases. MyoKardia’s initial focus is
on the treatment of heritable cardiomyopathies, a group of rare, genetically driven forms of heart failure that result from
biomechanical defects in cardiac muscle contraction. MyoKardia has used its precision medicine platform to generate a
pipeline of therapeutic programs for the chronic treatment of two of the most prevalent forms of heritable cardiomyopathy –
hypertrophic cardiomyopathy (HCM), and dilated cardiomyopathy (DCM). MyoKardia’s most advanced product candidate is mavacamten
(formerly MYK-461), a novel, oral, allosteric modulator of cardiac myosin intended to reduce hypercontractility. Mavacamten
has advanced into a pivotal Phase 3 clinical trial, known as EXPLORER-HCM in patients with symptomatic, obstructive HCM.
MyoKardia is also developing mavacamten in a second indication, non-obstructive HCM, in the Phase 2 MAVERICK clinical trial.
MYK-491, MyoKardia’s second product candidate, is designed to increase cardiac output in DCM patients by increasing the overall
extent of the heart’s cardiac contractility. MyoKardia is currently evaluating MYK-491 in a Phase 1b study in DCM patients. A
cornerstone of the MyoKardia platform is the Sarcomeric Human Cardiomyopathy Registry (SHaRe), a multi-center, international
repository of clinical and laboratory data on individuals and families with genetic heart disease, which MyoKardia helped form in
2014. MyoKardia’s mission is to change the world for patients with serious cardiovascular disease through bold and innovative
science.
(1) Ho, et al, Circulation 2018
Forward-Looking Statement
Statements we make in this press release may include statements which are not historical facts and are considered forward-looking
within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of
1934, as amended, which are usually identified by the use of words such as "anticipates," "believes," "estimates," "expects,"
"intends," "may," "plans," "projects," "seeks," "should," "will," and variations of such words or similar expressions. We intend
these forward-looking statements to be covered by the safe harbor provisions for forward-looking statements contained in Section
27A of the Securities Act and Section 21E of the Securities Exchange Act and are making this statement for purposes of complying
with those safe harbor provisions. These forward-looking statements, including statements regarding the clinical and therapeutic
potential of mavacamten, the initiation of patient dosing in the MAVA-LTE trial, mavacamten’s ability to achieve applicable
endpoints in the MAVA-LTE trial, the availability of data from the MAVA-LTE trial, the potential for data from the Company’s
clinical trials of mavacamten to support a marketing application, as well as the timing of these events, reflect our current views
about our plans, intentions, expectations, strategies and prospects, which are based on the information currently available to us
and on assumptions we have made. Although we believe that our plans, intentions, expectations, strategies and prospects as
reflected in or suggested by those forward-looking statements are reasonable, we can give no assurance that the plans, intentions,
expectations or strategies will be attained or achieved. Furthermore, actual results may differ materially from those described in
the forward-looking statements and will be affected by a variety of risks and factors that are beyond our control including,
without limitation, risks associated with the development and regulation of our product candidates, as well as those set forth in
our Quarterly Report on Form 10-Q for the quarter ended June 30, 2018, and our other filings with the SEC. Except as required by
law, we assume no obligation to update publicly any forward-looking statements, whether as a result of new information, future
events or otherwise.
Contacts:
Michelle Corral
Senior Director, Corporate Communications and Investor Relations
MyoKardia, Inc.
650-351-4690
ir@myokardia.com
Hannah Deresiewicz (investors)
Stern Investor Relations, Inc.
212-362-1200
Hannahd@sternir.com
Steven Cooper (media)
Edelman
415-486-3264
steven.cooper@edelman.com
