Skeletal Muscle Mass in COPD Improved With Bimagrumab

Bimagrumab, an activin type II receptor blockade, has demonstrated safety and efficacy in increasing skeletal muscle mass in patients with COPD, according to a study published in the American Journal of Respiratory and Critical Care Medicine. However, the treatment was not associated with improved functional capacity in patients.

This study included 67 participants with COPD (mean forced expiratory volume in 1 second [FEV₁] 1.05 L with 41.6% predicted) who were between 40 and 80 years of age. A total of 55 completed the study (82.1%). The primary end point was changes in the volume of thigh muscle, which were examined along with safety, tolerability, and 6-minute walking distance.

Thigh muscle volume showed significant improvements in those treated with bimagrumab vs placebo at week 4 (+5.9±3.4% vs 0.0±3.3%; P <.001), week 8 (+7.0±3.7% vs −0.7±2.8%; P <.001), week 16 (+7.8±5.1% vs −0.9±4.5%; P <.001), and week 24 (+5.0±4.5% vs -1.3±4.3%; P <.001). During the course of 6 months, 6-minute walking distance showed no significant increase. Bimagrumab was associated with mild muscle-related symptoms, acne, and diarrhea.

Individuals in this study had an appendicular skeletal muscle mass index ≤7.25 kg/m² for men and ≤5.45 kg/m² for women, as well as a body mass index <20 kg/m². Participants were administered 2 doses of either placebo (n=34) or intravenous bimagrumab 30 mg/kg (n=33) for the 6-month treatment period.

The researchers concluded, Blocking the action of negative muscle regulators through the activin type II receptors with bimagrumab treatment safely increased skeletal muscle mass but did not improve functional capacity in patients with COPD and low muscle mass.”

Disclosures: Drs Polkey, Singh, and Casaburi have received grants from Novartis. For a full list of disclosures, please refer to the reference.

Reference

Polkey MI, Praestgaard J, Berwick A, et al. Activin type II receptor blockade for treatment of muscle depletion in COPD: A randomized trial [published online August 10, 2018]. Am J Respir Crit Care Med. doi:10.1164/rccm.201802-0286O