A monoclonal antibody that blocks the activation of the skeletal muscle protein myostatin could be novel muscle-directed therapy for spinal muscular atrophy patients.
Cambridge, Mass.–based Scholar Rock (NSDQ:SRRK), which makes the SRK-015 investigational antibody, saw its shares more than double to $30.02 apiece yesterday. SRK-015 could lead to the formation of a new treatment category that targets and supports muscle fiber growth, according to the company.
The antibody has shown promise in a six-month clinical trial involving patients with type 2 (intermediate) and type 3 (mild) spinal muscular atrophy. Notably, all three treatment cohorts involved in the study reported improved muscle function.
Scholar Rock specializes in treating serious diseases with links to protein growth factors. Spinal muscular atrophy, which results from the lack of survival motor neuron (SMN) protein, is such a disease.
A double-blind high-dose randomized portion of the trial resulted in a 5.6 point improvement from baseline after six months on the Hammersmith Functional Motor Scale Expanded (HFMSE). By contrast, a low-dose arm resulted in a 2.4 gain on the scale.
Scholar Rock reported no safety concerns in the trial.
FDA has granted SRK-015 an orphan drug designation and a rare pediatric disease designation.
Scholar Rock anticipates 12-month data from the trial in the second quarter of 2021.
In 2018, Scholar Rock teamed up with Gilead Sciences to develop therapies to treat fibrotic diseases.