Our precision medicine platform has generated multiple programs to address a variety of disruptions in heart muscle contraction across different patient populations. We are advancing our research and development programs, each of which targets a distinct biomechanical defect that leads to either HCM or heritable DCM.
MYK-461 is an orally administered small molecule designed to reduce left ventricular contractility by allosterically modulating the function of cardiac myosin, the motor protein that drives heart muscle contraction. MyoKardia has evaluated MYK-461 in three Phase 1 clinical trials, primarily designed to evaluate safety and tolerability of oral doses of MYK-461, as well as provide pharmacokinetic and pharmacodynamic data. In April 2016, the U.S. FDA granted Orphan Drug Designation for MYK-461 for the treatment of symptomatic oHCM, a subset of HCM.
MyoKardia is currently studying MYK-461 in PIONEER-HCM, a Phase 2 open-label single-arm study to evaluate safety, tolerability and efficacy of MYK-461 in patients with symptomatic oHCM. The primary endpoint of PIONEER-HCM is the level of reduction in post-exercise left ventricular outflow tract (LVOT) gradient over 12 weeks of drug treatment. PIONEER-HCM will also explore the relationship between reduction in contractility and LVOT gradient, endpoints measuring functional capacity (i.e., exercise) and clinical symptoms in addition to gathering safety and tolerability data on MYK-461 in an outpatient setting.
MyoKardia is developing MYK-491, designed to treat dilated cardiomyopathy (DCM) by establishing normal contractility in a DCM heart. We intend to initiate a Phase 1 clinical trial of MYK-491 in the first half of 2017. Other product candidates include HCM-2, which is being developed to lower cardiac muscle contractility in HCM patients; and LUS-1 to counteract muscle disruption resulting in impaired relaxation of the heart.