Scholar Rock Announces Positive Opinion by the European Medicines Agency on Orphan Drug Designation for SRK-015 for the Treatment of Spinal Muscular Atrophy

Scholar Rock Holding Corporation (NASDAQ: SRRK), a clinical-stage biopharmaceutical company focused on the treatment of serious diseases in which protein growth factors play a fundamental role, today announced that the European Medicines Agency's (EMA's) Committee for Orphan Medicinal Products (COMP) has adopted a positive opinion recommending SRK-015 (human anti-promyostatin monoclonal antibody) for designation as an orphan medicinal product for the treatment of Spinal Muscular Atrophy (SMA).  SRK-015 was previously granted orphan drug designation by the U.S. Food and Drug Administration (FDA) in March 2018.

"We are delighted with the EMA COMP's adoption of a positive opinion for SRK-015 orphan drug designation, which represents another important milestone for this clinical program," said Nagesh Mahanthappa, PhD, President and CEO of Scholar Rock.  "We believe SRK-015 has the potential to be the first muscle-directed therapy to improve muscle function in patients with SMA and look forward to working with the EMA as we progress the program, including our intention to initiate a Phase 2 proof-of-concept study in the first quarter of 2019."

Orphan Medicinal Product Designation by the European Commission is available to companies developing products intended to treat a life-threatening or chronically debilitating condition that affects fewer than five in 10,000 people in the EU, and has the potential to be of significant benefit.  This designation could allow for a number of incentives, including protocol assistance, access to the centralized authorization procedure, reduced regulatory fees, and a 10-year period of marketing exclusivity in the EU after product approval.

About SRK-015
SRK-015is a selective inhibitor of the activation of myostatin and is an investigational product candidate for the treatment of patients with spinal muscular atrophy (SMA).  Myostatin, a member of the TGF-beta superfamily of growth factors, is expressed primarily by skeletal muscle cells and the absence of its gene is associated with an increase in muscle mass and strength in multiple animal species.  Scholar Rock believes the inhibition of the activation of myostatin with SRK-015 may promote a clinically meaningful increase in muscle mass and strength.  A Phase 1 clinical trial in healthy volunteers is ongoing.  The effectiveness and safety of SRK-015 have not been established and SRK-015 has not been approved by the FDA or any other regulatory agency.

About SMA
Spinal muscular atrophy (SMA) is a rare, and often fatal, genetic disorder that typically manifests in young children. An estimated 30,000 to 35,000 patients are afflicted with SMA in the United States and Europe. It is characterized by the loss of motor neurons, atrophy of the voluntary muscles of the limbs and trunk and progressive muscle weakness. The underlying pathology of SMA is caused by insufficient production of the SMN (survival of motor neuron) protein, essential for the survival of motor neurons and is encoded by two genes, SMN1 and SMN2.  While there has been progress in the development of therapeutics that address the underlying SMA genetic defect, there continues to be a high unmet need for therapeutics that directly address muscle atrophy.

About Scholar Rock
Scholar Rockis a clinical-stage biopharmaceutical company focused on the discovery and development of innovative medicines for the treatment of serious diseases in which signaling by protein growth factors plays a fundamental role.  Scholar Rock is creating a pipeline of novel product candidates with the potential to transform the lives of patients suffering from a wide range of serious diseases, including neuromuscular disorders, cancer, fibrosis and anemia.  Scholar Rock's newly elucidated understanding of the molecular mechanisms of growth factor activation enabled it to develop a proprietary platformfor the discovery and development of monoclonal antibodies that locally and selectively target these signaling proteins at the cellular level.  By developing product candidates that act in the disease microenvironment, the Company intends to avoid the historical challenges associated with inhibiting growth factors for therapeutic effect.