Scholar Rock’s Phase 1 study of SRK-015 delivers positive interim data

By Mateen Dalal

Scholar Rock Holding Corporation, the clinical-stage biopharma company focusing on treating serious diseases which are affected by protein growth factors, has recently confirmed positive interim results for its Phase 1 multiple and single-ascending dose clinical trial of SRK-015 among healthy adult volunteers.

For the record, SRK-015 is a highly specific myostatin activation inhibitor, and it was observed that the product was well tolerated with no apparent safety signals. Supposedly, by displaying sustained and robust target engagement in human subjects, latent myostatin’s pharmacologic effects on serum concentration demonstrate the initial proof-of-mechanism for this unique therapeutic method.

According to Scholar Rock, the promising interim pharmacodynamic (PD), pharmacokinetic (PK) as well as safety and tolerability data would support advancement of SRK-015 towards a Phase 2 proof-of-concept clinical study in spinal muscular atrophy (SMA) patients, where a once every 4-week dosing regimen will be evaluated.

Scholar Rock’s Chief Medical Officer, Yung Chyung, M.D., said that the company continues to work in the direction of developing its lead antibody candidate as potentially the first muscle-directed therapy to treat SMA. The firm would look to initiate the Phase 2 trials for evaluating SRK-015’s potential in tackling the functional deficits which still have considerable unmet need in SMA, Dr. Chyung mentioned.

The company informed that the Phase 1 trial was designed as double-blind, randomized and placebo-controlled study to evaluate safety as well as tolerability of SRK-015 administered intravenously, assess the PK and PD profile, in addition to inform dosing for the Phase 2 trial.

The trial’s immunogenicity and safety data showed that SRK-015 was well tolerated, having no dose-limiting toxicities recognized up to 30 mg/kg, which was the highest evaluated dose. Scholar Rock also confirmed that no deaths occurred, no serious adverse events (AEs) and discontinuations owing to any AE associated with the treatment were observed, also there were no hypersensitivity reactions.

Nagesh Mahanthappa, Ph. D., CEO and President of Scholar Rock, stated that the interim Phase 1 results not only offer initial proof-of-mechanism for SRK-015’s pharmacologic potential, but also the company’s therapeutic approach of targeting the latent forms of growth factors specifically.