People taking semaglutide for obesity lost less lean mass over a full year when they also received an experimental antibody called trevogrumab, according to Phase 2 results Regeneron announced on October 1, 2026. At the 75 mg dose, lean mass fell 4.2%, compared with 7.3% on semaglutide plus placebo, which works out to about 42% less lean mass loss.
The trial was sponsored by Regeneron, which also reported the results. The full paper is in press with The Lancet but has not yet been published. Trevogrumab has not been evaluated or approved by any regulatory authority, so it is available only in clinical trials.
