In an eight-week study of obese non-human primates, iBio's Activin E antibody IBIO-610 combined with semaglutide produced weight loss that was 93% fat, compared with 77% in animals receiving semaglutide alone. A single intravenous dose suppressed active Activin E by 97% at week 8 with a 33.2-day half-life, which the company projects could support twice-yearly dosing in humans. Group sizes were six animals, total weight lost was not disclosed, and first-in-human trials are planned for the first half of 2027.
Key Points
- Combination therapy: 93% of weight lost was fat versus 77%
- Single dose suppressed active Activin E by 97% at week eight
- Six animals per group; human trials targeted for 2027
Longevity Analysis
Pharmacological weight reduction is not metabolically neutral — the proportion of lean tissue sacrificed determines whether an intervention improves or erodes functional capacity in later decades. Muscle governs glucose disposal, metabolic rate, skeletal loading and fall resistance, so a therapy that redirects loss toward adipose tissue addresses a known liability of GLP-1 receptor agonists in older patients. The finding also reframes how weight-loss response should be interpreted: scale weight alone misreads the signal, while body composition tracking distinguishes fat reduction from the slow attrition of tissue that becomes progressively harder to rebuild.
Original published by Longevity.Technology, by Kyle Umipig.