Scholar Rock is developing SRK-015, a drug that specifically blocks the latent form of myostatin in order to increase muscle mass and potentially treat spinal muscular atrophy (SMA). Myostatin is a member of the TGF-beta superfamily of growth factors, and the specificity of SRK-105 is intended to prevent the drug from blocking the myostatin receptor, activated myostatin, or any other member of thi...