Roche is making a big bet on the future of weight-loss drugs, licensing an experimental obesity treatment from South Korea’s Hanmi Pharmaceutical designed to do something today’s blockbusters can’t: melt fat while preserving muscle.
Announced August 24, 2026, the deal gives Roche rights to HM17321 outside South Korea for $190 million upfront plus up to $2.3 billion in development, regulatory and commercial milestones, plus royalties. Hanmi will finish the Phase 1 trial before Roche takes over development.
A different mechanism
HM17321 is a urocortin 2 analog, an injectable designed to activate a pathway that stimulates muscle growth and fat metabolism — a contrast to GLP-1 drugs like Zepbound and Wegovy. “The paradigm of obesity treatment is evolving beyond simple weight reduction toward improving body composition,” said Hanmi’s R&D head.
Why lean mass matters
Powerful GLP-1 drugs cause people to lose both fat and healthy muscle during rapid weight loss — a growing concern, especially for older patients. The industry increasingly sees lean-mass-sparing drugs as the next generation, improving overall body composition and metabolic health rather than just the number on the scale. The drug is still early (Phase 1 began in November 2025), but Hanmi says it holds a head start over rivals working on similar approaches.