Ascletis bets on once-monthly ASC36 to fight obesity

HONG KONG, Oct. 30, 2025 /PRNewswire/ -- Ascletis Pharma Inc. (HKEX: 1672, "Ascletis") announces that it has selected ASC36, a once-monthly, potentially best-in-class subcutaneously administered amylin receptor agonist, as a clinical development candidate. Ascletis expects to submit an Investigational New Drug Application (IND) for ASC36 for the treatment of obesity to the U.S. Food and Drug Administration (FDA) in the second quarter of 2026.

ASC36, an amylin receptor peptide agonist, was discovered and developed in-house utilizing Ascletis' Artificial Intelligence-Assisted Structure-Based Drug Discovery (AISBDD) and Ultra-Long-Acting Platform (ULAP) technologies. ASC36 is engineered for a longer observed half-life (as measured by time to 50% C_max) and higher bioavailability per milligram of peptide to support once-monthly subcutaneous (SQ) dosing, with injection volume of one milliliter or less. These engineered properties also allow for scalability advantages in manufacturing.

In head-to-head non-human primate (NHP) studies, ASC36 slow-release SQ depot formulations had an average observed half-life of approximately 15 days, 3-fold longer than petrelintide, supporting ASC36 as a potential once-monthly treatment for obesity in humans.

In a head-to-head diet-induced obese (DIO) rat study, which is well established as being highly predictive of human efficacy, dosed with equal molar concentrations of ASC36 and petrelintide, ASC36 reduced body weight by 10.01%, compared to 5.25% for petrelintide, a relative increase in efficacy of 91% (Table 1). This superior weight loss per milligram of peptide may also provide scalability advantages in manufacturing.

Table 1. ASC36 demonstrated statistically and significantly more weight loss than petrelintide in DIO rats after 7-day treatment

ASC36 has excellent chemical and physical stability with no fibrillation around neutral pH, allowing for co-formulation with other peptides including ASC35, a GLP-1R/GIPR dual agonist.

ASC36's longer observed half-life, better SQ bioavailability and greater weight loss demonstrate its potential as a best-in-class once-monthly treatment for obesity.

"Our focus has always been on developing novel approaches to expand options for the treatment of obesity and other metabolic diseases," said Jinzi Jason Wu, Ph.D., Founder, Chairman and CEO of Ascletis, "The preclinical characterization of ASC36 suggests potential best-in-class efficacy with once-monthly dosing resulting in superior weight loss and a more versatile and patient friendly titration schedule."

Monotherapy and Combination Studies with ASC36

ASC36 monotherapy is being developed as a cornerstone therapy for the treatment of cardio-metabolic diseases including obesity, meanwhile ASC36-based combination therapies are being developed. Ascletis plans to combine ASC36, an amylin receptor agonist, with its once-monthly subcutaneously administered ASC35, a GLP-1R/GIPR dual agonist, to treat obesity.

Ascletis' AISBDD and ULAP technologies enable the Company to design, optimize and develop multiple once-monthly SQ ultra-long-acting peptides, including ASC35 and ASC36. Based on the properties of peptides, the Company can design, through its proprietary ULAP technology, various slow-release constants (k) for peptides in SQ depots to precisely release injected peptides over desired dosing intervals to reduce peak-to-trough ratios and improve clinical outcomes.

For more information, please visit www.ascletis.com.