Ascletis Pharma Inc. (HKEX: 1672) has announced the selection of ASC36, a once-monthly subcutaneous (SQ) amylin receptor agonist, as a clinical development candidate for obesity treatment. The company plans to submit an Investigational New Drug (IND) application to the U.S. Food and Drug Administration (FDA) in the second quarter of 2026.
Extended Half-Life and Enhanced Efficacy
ASC36 was developed in-house using Ascletis’ Artificial Intelligence-Assisted Structure-Based Drug Discovery (AISBDD) and Ultra-Long-Acting Platform (ULAP) technologies. The peptide has been engineered for a longer half-life and improved bioavailability per milligram, enabling once-monthly SQ administration with an injection volume of one milliliter or less.
In head-to-head non-human primate (NHP) studies, ASC36 demonstrated an average half-life of approximately 15 days, about three times longer than petrelintide. This extended profile supports its potential as a once-monthly treatment for obesity.
In a diet-induced obese (DIO) rat study — considered a predictive model for human efficacy — ASC36 achieved a 10.01% reduction in body weight, compared to 5.25% for petrelintide at equal molar concentrations. This represents a 91% relative improvement in efficacy (p < 0.0001 vs petrelintide). The greater weight reduction per milligram of peptide may also translate into manufacturing scalability benefits.
Table 1. Comparative Weight Loss in DIO Rats After 7 Days
|
Group |
Dosing |
Total Body weight change |
Relative weight loss vs petrelintide |
|
Vehicle |
SQ, Q2D |
+1.05% |
|
|
ASC36 (10 nmol/kg) |
SQ, Q2D |
−10.01% (p < 0.0001 vs vehicle) |
91% (p < 0.0001 vs petrelintide) |
|
Petrelintide (10 nmol/kg) |
SQ, Q2D |
−5.25% (p < 0.0001 vs vehicle) |
|
Note: DIO = diet-induced obese; SQ = subcutaneous; Q2D = once every two days.
Stability and Co-Formulation Potential
ASC36 demonstrated excellent chemical and physical stability with no fibrillation near neutral pH, enabling co-formulation with other peptides, including ASC35, a GLP-1R/GIPR dual agonist also developed by Ascletis.
The company noted that ASC36’s longer half-life, better SQ bioavailability, and superior weight loss position it as a potential best-in-class therapy for obesity.
CEO Statement
“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, offering superior weight loss and a more patient-friendly titration schedule.”
Monotherapy and Combination Development
Ascletis plans to pursue both monotherapy and combination therapy approaches. ASC36 is being advanced as a cornerstone therapy for cardiometabolic diseases, while combination regimens pairing ASC36 with ASC35 are under development for obesity treatment.
Leveraging its ULAP technology, Ascletis can fine-tune slow-release kinetics for peptides in SQ depots to optimize dosing intervals, reduce peak-to-trough ratios, and improve clinical outcomes.
Upcoming Conference Call
Ascletis will host a conference call in Mandarin at 10:00 a.m. China Standard Time on October 30, 2025, via Zoom (Meeting ID: 978 3932 9387).
About Ascletis Pharma Inc.
Ascletis Pharma Inc. is a fully integrated biotechnology company focused on developing and commercializing best-in-class and first-in-class therapeutics for metabolic diseases. Its proprietary AISBDD and ULAP technologies have supported the in-house development of multiple drug candidates, including ASC30, a small molecule GLP-1R agonist being evaluated for once-daily oral and once-monthly to once-quarterly injectable regimens for chronic weight management.
The company is listed on the Hong Kong Stock Exchange under ticker 1672.HK.
