Scholar Rock Granted Orphan Drug Designation by the FDA for SRK-015

for the Treatment of Patients with Spinal Muscular Atrophy

CAMBRIDGE, Mass., March 29, 2018 – Scholar Rock, a biopharmaceutical company focused on developing medicines for the treatment of serious diseases in which signaling by protein growth factors plays a fundamental role, today announced that the U.S. Food and Drug Administration (FDA) has granted Orphan Drug Designation (ODD) to its lead antibody product candidate, SRK-015, for the treatment of spinal muscular atrophy (SMA). SRK-015 is an inhibitor of the activation of myostatin, which Scholar Rock believes has the potential to be the first muscle-directed therapy to reverse or prevent muscle atrophy in SMA patients and could be used both as a monotherapy or in conjunction with the current standard of care.

We are very pleased that the FDA granted Orphan Drug Designation to SRK-015 for the treatment of patients suffering from SMA, and we appreciate that the agency’s decision came much earlier than anticipated,” said Nagesh Mahanthappa, PhD, President and Chief Executive Officer of Scholar Rock. “This designation is an important milestone in the development of our lead product candidate along the path towards a first-in-human Phase 1 clinical trial in the second quarter of 2018