Longevity & AgingGLP-1 Drugs May Accelerate Muscle Loss After Stopping Treatment New Data Warns
New preclinical research from biotech Eos SENOLYTIX compared semaglutide with its experimental compound PTC-2105 in aging mice over more than a year. The findings suggest that mice cycled on and off semaglutide showed signs of accelerated late-life muscle loss, resembling a sarcopenic pattern. Meanwhile, PTC-2105, a mitochondrial-targeting compound designed to eliminate senescent cells, appeared to reduce fat mass more than semaglutide while also increasing lean mass and physical performance. The data, presented at an obesity innovation forum, adds a longevity lens to a field that has largely focused on weight reduction alone. While mouse studies cannot predict human outcomes, the research raises important questions about what happens to body composition after GLP-1 treatment ends, especially in older adults already at risk for frailty and muscle decline.
