Scholar Rock, a biotechnology company based in Boston, recently announced that it has completed dosing of the first cohort and is continuing enrollment of healthy volunteers in its Phase 1 clinical trial of SRK-015. SRK-015, a selective inhibitor of the activation of myostatin, is the company’s lead antibody drug candidate. Scholar Rock believes it has the potential to be the first muscle-directed therapy to reverse or prevent further muscle atrophy in patients with spinal muscular atrophy (SMA) and could be used alone or in conjunction with the current standard of care.
The placebo-controlled, double-blind Phase 1 clinical trial will evaluate the safety, tolerability, pharmacokinetics and pharmacodynamics of single- and multiple-ascending doses of intravenous SRK-015 in healthy adult volunteers. Assuming the successful completion of the Phase 1 trial, the company plans to initiate a Phase 2 proof-of-concept trial in the first quarter of 2019 to evaluate the efficacy and safety of SRK-015 in patients with later-onset SMA as a monotherapy or in conjunction with an approved SMN upregulating therapy.
SRK-015 works by inhibiting myostatin. Myostatin is a protein that works with other proteins and hormones to help regulate muscle mass. In healthy individuals, myostatin limits muscle growth and differentiation, to prevent muscles from growing too large. For individuals affected by SMA, inhibiting this protein may combat the muscle weakness and atrophy that characterizes the disease. A Phase 1 clinical trial in healthy volunteers is ongoing. The U.S. Food and Drug Administration (FDA) has granted Orphan Drug Designation (ODD) for SRK-015 for the treatment of SMA.