Announcement • May 19
Harbour BioMed Announces Preclinical Data For LET003, Its First AI-Enabled Drug Candidate Harbour BioMed, a global biopharmaceutical company committed to the discovery and development of novel antibody therapeutics in immunology, oncology and other disease areas, announced preclinical data for LET003, its first next-generation ACVR2A/2B-targeting monoclonal antibody developed using the Hu-mAtrIx™ platform. The results showed that LET003 exhibited superior pharmacokinetic characteristics compared to multiple competitor molecules. When combined with semaglutide, LET003 significantly enhanced fat reduction while effectively preserving lean mass. In addition, LET003 achieved lean mass-promoting effects at lower dose level comparable to bimagrumab at higher dose level, highlighting its potential to become a best-in-class therapy for obesity treatment. The ACVR2A/2B signaling pathway plays a critical role in regulating the balance between fat and muscle mass in the body. Previously, bimagrumab, the first antibody targeting ACVR2A/2B, demonstrated positive clinical results, showing favorable efficacy and safety in combination with semaglutide for obesity treatment. Building on these findings, Harbour BioMed successfully advanced the molecular optimization and functional enhancement of LET003 through structure biology and Hu-mAtrIxTM, its AI platform-driven antibody engineering approaches. In human FcRn transgenic mouse and cynomolgus monkey models, researchers compared the blood clearance rates of LET003 with several competing molecules following subcutaneous administration. Results showed that LET003 exhibited significantly slower clearance than all comparator molecules tested, suggesting that it may achieve comparable efficacy with longer dosing intervals or lower doses relative to competing therapies. In an obesity model using wild-type mice, semaglutide (30 nmol/kg) and LET003 (20 mg/kg) were administered subcutaneously once weekly as monotherapies or in combination. Results after three weeks of treatment showed: LET003 in combination with semaglutide decreased fat mass by 76.0% compared with vehicle (P. In the combination group, lean mass decreased by 6.5% compared with vehicle (P=0.0001), but increased by 5.7% compared with semaglutide monotherapy (P=0.0007). These data suggest that combining LET003 with semaglutide can significantly enhance fat reduction while effectively mitigating the lean mass loss associated with semaglutide treatment alone. In a high-fat diet-induced obesity model using human FcRn transgenic mice, semaglutide (30 nmol/kg) and LET003 (20 mg/kg) were administered subcutaneously once weekly as monotherapies or in combination. Results after three weeks of treatment showed: The fat-to-body weight ratio in the combination group was reduced by 17.5% compared with vehicle (PGLP-1-based weight loss therapies can further reduce body fat while effectively mitigating lean mass loss. LET003 is the first ACVR2A/2B dual-target blocking antibody developed using the Hu-mAtrIx™ artificial intelligence platform. It has demonstrated superior pharmacokinetic properties compared with several competing molecules and, in preclinical animal models, has shown enhanced fat reduction and lean mass preservation effects when used in combination with GLP-1 therapies. 2142
Live News • May 18
Harbour BioMed Unveils AI-Enabled Antibody With Promising Obesity Preclinical Results Harbour BioMed reported preclinical data for LET003, its first AI-enabled monoclonal antibody targeting ACVR2A/2B, developed on its Hu-mAtrIx platform.
LET003 showed superior pharmacokinetic characteristics compared with multiple competitor molecules in preclinical testing.
In combination with semaglutide, LET003 led to significant fat reduction while preserving lean mass in preclinical obesity models, highlighting its potential for obesity treatment.
This update points to early-stage validation of Harbour BioMed’s AI-driven discovery platform and suggests the company is trying to position LET003 as a potential best-in-class obesity therapy candidate if future studies support the preclinical findings.
Investors should keep in mind that these results are preclinical, so the key watchpoints from here are progression into clinical trials, safety outcomes and any partnership or licensing discussions that might emerge around this asset or the Hu-mAtrIx platform. Announcement • Apr 17
Harbour Biomed Appoints Adam Zong as President Harbour BioMed announced the appointment of Dr. Adam Zong as President. Dr. Zong will be based in Shanghai and report directly to Dr. Jingsong Wang, Founder, Chairman and Chief Executive Officer of Harbour BioMed. In this role, Dr. Zong will be responsible for strengthening the Company's internal product pipeline, advancing the strategic development of its overall portfolio, and leading asset strategy and partnership initiatives. He will also play a key role in aligning cross-functional efforts to accelerate development timelines and maximize the value of the Company's pipeline. Dr. Zong brings more than 20 years of global biopharma leadership experience, with a strong track record in portfolio strategy, commercial operations, and business development. His experience spans both multinational pharmaceutical companies and emerging biotechnology organizations. Prior to joining Harbour BioMed, Dr. Zong served as Principal Consultant at Arc Nouvel Clinical Development Consulting. He also served as the founding Chief Executive Officer of Hengrui Therapeutics U.S., where he led the company's global expansion. Earlier in his career, he held senior leadership roles at Merck & Co., Bristol Myers Squibb, Schering-Plough, and Pfizer, where he managed global franchises, oversaw large-scale commercial portfolios, and led significant business development, licensing, and M&A transactions. Dr. Zong received his Ph.D. in Oncology and Virology from Rockefeller University and holds an MBA in Finance and Entrepreneurial Management from The Wharton School of the University of Pennsylvania. 
