Bone Abstracts

Loss of skeletal muscle mass and function in humans is associated with significant morbidity and mortality. The role of myostatin as a key negative regulator of skeletal muscle mass and function has supported the concept that inactivation of myostatin could be a useful approach for treating muscle wasting diseases. The human monoclonal antibody REGN1033 is a specific and potent myostatin antagonist. Treatment of mice with REGN1033 increased muscle fiber size, muscle mass, and force production. REGN1033 was also tested in monkeys and healthy volunteers where it increased lean muscle mass to a similar extent, but less than in mice. However, short-term effects of REGN1033 on mass and function in the elderly with sarcopenia were modest. In this presentation, I will present our extensive muscle and serum profiling data with REGN1033 in mice, monkeys, and humans with the idea that this translational approach will predict human efficacy of novel agents prior to going into the clinic.