ASC47

ASC47 is an adipose-targeted, ultra-long-acting, subcutaneously injected small molecule agonist of thyroid hormone receptor beta (THRβ), discovered and developed by Ascletis. It is designed as a muscle-preserving weight loss drug candidate for the treatment of obesity. ASC47 demonstrates unique adipose tissue targeting, resulting in high drug concentrations in fat tissue and dose-dependent effects. Its mechanism involves selective activation of THRβ in adipose tissue, leading to UCP-1-mediated thermogenesis—an increase in energy expenditure through heat production—which promotes fat loss while preserving muscle mass. In preclinical models and early clinical studies, ASC47 has shown a long half-life (up to 40 days), supporting once-monthly or once-bimonthly dosing regimens. Clinical data indicate that it produces gradual weight loss with muscle preservation compared to incretin-based drugs like semaglutide. Combination therapy with semaglutide has demonstrated superior weight reduction and metabolic benefits over monotherapy[1][2][3][4][5][6][7][8][9].