March 13, 2014

Barcelona, Spain, March 13, 2014 – A new drug being developed for the treatment of a rare muscle wasting disease called sporadic inclusion body myositis (sIBM), and which is being investigated in sarcopenia in elderly patients, has also been shown to speed the recovery of muscle mass in young men whose muscles have atrophied as a result of wearing a cast.

In the study sponsored by Novartis, 24 healthy men who had one leg immobilized in a cast for two weeks received either placebo or a single dose of the drug bimagrumab (BYM338) upon cast removal. Over the following 12 weeks, assessments were conducted to determine thigh muscle volume, total lean body mass, muscle strength and side effects. In subjects receiving the drug, thigh muscle volume returned to pre-cast levels within four weeks of cast removal, compared to 12 weeks among those who received placebo. Side effects were mostly mild and all subjects completed the study. The research was presented at the International Conference on Frailty and Sarcopenia Research (ICFSR) in Barcelona, Spain.

Bimagrumab is a monoclonal antibody being developed by Novartis. It is an Investigational drug from a small study and has not been submitted for approval. Additional clinical trials and development are being conducted to understand its safety and efficacy. Laboratory studies have shown that bimagrumab stimulates muscle growth by binding to a receptor on muscle cells that normally binds a protein called myostatin, which inhibits muscle growth. The drug is being developed for the treatment of sIBM, and is also being investigated in age-related sarcopenia as well as other common muscle wasting conditions seen in patients with cancer, chronic obstructive pulmonary disease (COPD) and those on mechanical ventilators. The drug also recently received breakthrough therapy status from the FDA for the treatment of sIBM.

Sarcopenia, the age-related loss of muscle mass and strength contributes to an elevated risk of disability and loss of function in the elderly. Despite the fact that it is one of the most striking features of aging and affects up to 40% of people over the age of 60, there remain many unanswered questions about its causes and how to treat it. Clinical and basic research aimed at identifying the underlying mechanisms were featured throughout the ICFSR. This bimagrumab trial provides both a path forward for treatment and clues about mechanism, said Marco Pahor, M.D., Director of the Institute on Aging at the University of Florida College of Medicine. “These results suggest that regulation of myostatin expression is involved in the development of human sarcopenia.”

ICSFR2014 press release in PDF format