Hanmi Pharmaceutical Unveils Muscle-Enhancing Obesity Drug at U.S. Conference

The obesity treatment industry is increasingly focusing on 'high-quality weight loss,' which effectively reduces body fat while preserving or enhancing muscle mass. In this context, Hanmi Pharmaceutical garnered attention by unveiling the world's first peptide-based muscle-enhancing obesity drug, LA-MSTN (HM500197), at the American Diabetes Association (ADA 2026) conference held in New Orleans.
Hanmi's presentation on June 7 highlighted a new direction in obesity treatment development, addressing the muscle loss issues associated with GLP-1-based therapies and reducing the risk of weight regain.
On June 16, Hanmi reported that the ADA 2026 event was bustling with attendees eager to learn about the research findings on the muscle-enhancing obesity drug. The company noted that researchers and industry representatives from around the world showed significant interest in the development strategies and unique features of the new obesity treatments HM17321 and HM500197.
HM500197 is the first peptide-based substance designed to selectively inhibit myostatin, a key regulator of muscle growth.
While GLP-1-based obesity treatments can lead to a weight loss of 15-20% through appetite suppression, they have been criticized for causing muscle loss and a decrease in basal metabolic rate, which can result in weight regain after discontinuation. This has led to increased attention on combination studies that regulate the myostatin and activin pathways involved in muscle growth.
According to Hanmi, in vitro studies showed that HM500197 exhibited myostatin inhibition activity comparable to that of the antibody-based muscle-preserving drug, bimagrumab, without any observed inhibitory activity against non-target cytokines, demonstrating excellent selectivity for myostatin.
In vivo studies revealed superior skeletal muscle-selective lean mass gain compared to bimagrumab, while minimizing off-target effects, indicating differentiated safety results.
Notably, in a mouse model of obesity induced by a high-fat diet, HM500197 demonstrated a dose-dependent increase in lean mass while selectively enhancing skeletal muscle mass. When administered in combination with GLP-1 class drugs, it effectively suppressed muscle loss while promoting fat-centric weight loss, providing scientific evidence for its potential in 'healthy weight loss' treatment.
Hanmi also reported that another muscle-enhancing obesity drug, LA-UCN2 (HM17321), is currently undergoing Phase 1 clinical trials in the U.S. At the conference, the company presented seven studies exploring the therapeutic potential of various mechanisms of action, including cardiovascular and kidney protection.