Cambridge, MA, Rotterdam, NL, Suzhou, CN— Nov 25, 2022

Harbour BioMed (the “Company”, HKEX: 02142), today announced that the Company will release the progress of its next-generation fully human heavy-chain antibody porustobart (HBM4003) with dual MOA of CTLA-4 inhibition and Treg depletion, in the study of combination therapy with anti-PD-1 antibody at the European Society for Medical Oncology Immuno-Oncology (ESMO I-O) 2022 Annual Congress, taking place in Geneva, Switzerland and online from December 7-9, 2022.

Details for the presentation:

Title: A Phase I Study of HBM4003, an anti-CTLA-4 Heavy Chain Only Monoclonal Antibody, in Combination with Toripalimab in Advanced Melanoma

Abstract number: 243

Publication Format: Poster

Porustobart (HBM4003) has demonstrated strong efficacy and excellent safety profile. It is believed that this product will have the potential to lead the development of next-generation therapy of immuno-oncology, especially combination therapeutics. Harbour BioMed is developing porustobart as part of its broad and innovative immuno-oncology pipeline to address significant unmet medical needs in many solid tumor indications.

About Porustobart

Porustobart is a fully human anti-CTLA-4 monoclonal heavy chain only antibody (HCAb) generated from Harbour Mice^®. It is the first fully human heavy-chain-only monoclonal antibody entered into clinical stage globally. By enhancing antibody-dependent cell cytotoxicity (ADCC) killing activity, porustobart has demonstrated significantly improved depletion specific to high CTLA-4 expressing Treg cells in tumor tissues. The potent anti-tumor efficacy and differentiated pharmacokinetics with durable pharmacodynamic effect presents a favorable product profile. This novel and differentiated mechanism of action has the potential to improve efficacy while significantly reducing the toxicity of the drug in monotherapy and combination therapy.

About Harbour BioMed

Harbour BioMed (HKEX: 02142) is a global biopharmaceutical company committed to the discovery, development and commercialization of novel antibody therapeutics focusing on immunology and oncology. The Company is building its robust portfolio and differentiated pipeline through internal R&D capability, collaborations with co-discovery and co-development partners and select acquisitions.
 
The Company’s proprietary antibody technology platforms Harbour Mice^® generate fully human monoclonal antibodies in two heavy and two light chain (H2L2) format, as well as heavy chain only (HCAb) format. Building upon the HCAb antibodies, the HCAb-based immune cell engagers (HBICE^®) are capable of delivering tumor killing effects unachievable by traditional combination therapies. Integrating Harbour Mice^®, HBICE^® with single B cell cloning platform, our antibody discovery engine is highly unique and efficient for development of next generation therapeutic antibodies.