Bimagrumab
Also known as: BYM338
Status
In trials. Not approved. In clinical development. Note that it is an antibody, not a peptide: it is not interchangeable with anything in the peptide category and is not something that can be reconstituted from a powder.
What it is
A monoclonal antibody studied for holding onto muscle while fat is lost.
What published research measured
A human monoclonal antibody that blocks the activin type II receptor, the pathway myostatin signals through to limit muscle growth. A phase 2 trial in adults with obesity and type 2 diabetes reported loss of fat mass alongside a gain in lean mass, which is the reverse of what happens on an incretin alone — roughly a quarter of the weight lost on GLP-1 agonists is lean tissue. It is now being studied in combination with tirzepatide and semaglutide rather than on its own.
Source
Heymsfield SB et al. 2021 — Effect of Bimagrumab vs Placebo on Body Fat Mass Among Adults With Type 2 Diabetes and Obesity: A Phase 2 Randomized… · Rooks D et al. 2017 — Treatment of Sarcopenia with Bimagrumab: Results from a Phase II, Randomized, Controlled, Proof-of-Concept Study · Melson E et al. 2025 — What is the pipeline for future medications for obesity?
Sources
No linked primary source is on file for this entry yet.
Educational use only, never medical advice. No doses.