HANXBIO-B (03378) announced that the company presented four core preclinical research results in poster sessions at the 2026 American Association for Cancer Research (AACR) Annual Meeting, held from April 17 to 22 in San Diego, USA. The presentations further validate the company's research and development capabilities and innovation strength. The research findings are as follows:

1. CTLA-4/SIRPα Bispecific Fusion Protein HX044 HX044 is a globally innovative CTLA-4/SIRPα bispecific fusion protein and a next-generation CTLA-4-targeted therapy. It works by simultaneously targeting CTLA-4 and CD47 to enhance the depletion of regulatory T-cells in the tumor microenvironment, thereby reducing immune suppression against the tumor and boosting anti-tumor activity. Its primary development focus is for PD-1/ICI-resistant solid tumors, forming a synergistic and complementary oncology immunotherapy pipeline with the company's HX009. Study Title: Preclinical Pharmacokinetic and Pharmacodynamic Modeling of Novel CTLA4xCD47 Bispecific Antibody HX044 — Evaluation of Therapeutic Window Compared to Ipilimumab Results: - The proportion of CD47+/CTLA4+ double-positive Tregs was significantly higher in various human tumor tissues compared to peripheral blood, with higher CTLA4 expression, providing a precise targeting basis for HX044. - HX044 demonstrated a wider therapeutic window (potentially approximately 4 times wider) than ipilimumab, based on a lower effective dose and no significant change in the dose associated with immune-related adverse events. These positive preclinical data provide a solid foundation for the clinical development of HX044, which is currently in Phase I clinical trials.

2. Bispecific Antibody-Drug Conjugate (BsAbADC) HX116 HX116 is a potential first-in-class bispecific antibody-drug conjugate (BsAbADC) independently developed by the company. It targets PD-(L)1 and VEGF and incorporates additional mechanisms of action, such as direct killing and enhanced anti-tumor immunity via immunogenic cell death, thereby increasing anti-tumor activity and holding significant market potential. In preclinical studies, HX116 demonstrated superior activity compared to its parent BsAb. Study Title: Potential Synergistic Efficacy Study of Novel Multi-Mechanism PD-L1xVEGF Antibody-Drug Conjugate HX116 for Solid Tumor Treatment Results: - HX116 can bind to and be internalized by PD-L1+ cells, and this binding and internalization are enhanced in the presence of VEGF. - HX116 effectively internalizes into PD-L1+ tumor organoids and induces cytotoxicity comparable to the clinically leading PD-L1-ADC drug SGN-PDL1V. - The three mechanisms of action of HX116 collectively contribute to its anti-tumor activity, with effects superior to its parent bispecific antibody (BsAb).

3. PD-L1-Targeting ADC HX112 HX112 is a novel PD-L1-targeting ADC independently developed by the company. It combines tumor-specific killing with immune checkpoint inhibition and is intended for the treatment of a broad range of solid tumors. Study Title: A Novel Multi-Mechanism PD-L1 Antibody-Drug Conjugate — A Potential Therapeutic Candidate for Pan-Solid Tumors with Enhanced Tumor Specificity Results: - Efficient Internalization in 3D Tumor Organoids: While most PD-L1 ADCs showed weak internalization and cytotoxicity in 2D cells (with the exception of SGN-PDL1V), HX112 demonstrated internalization ability and cytotoxicity comparable to SGN-PDL1V in 3D organoids. If 3D tumor organoids more closely resemble the real tumor phenotype, HX112 may possess greater tumor specificity than SGN-PDL1V. - Potential to Avoid TME-Release Design, Reducing Side Effects: If HX112 can be effectively internalized into tumor cells, it might not require a tumor microenvironment (TME)-release linker, potentially avoiding side effects associated with that mechanism.

4. 3D Tumor Organoid ADC Evaluation System This research validates the company's innovative preclinical ADC evaluation system, demonstrating that 3D tumor organoids are superior to 2D cells in predicting a drug's in vivo anti-tumor efficacy. Study Title: 3D Tumor Organoids Outperform 2D Cells in More Accurately Predicting the In Vivo Anti-Tumor Efficacy of Antibody-Drug Conjugates Results: - PD-L1 antibodies targeting different epitopes showed vastly different internalization and toxicity profiles in 2D cells, but exhibited comparable activity in 3D organoids, which was highly consistent with results from in vivo CDX models. - 3D tumor organoids are better than 2D cells at predicting in vivo efficacy. Utilizing tumor organoids can serve as a more robust and simplified method for evaluating preclinical ADC candidate molecules.

The company will continue to advance the development of its innovative drug pipeline, committed to providing more effective and safer treatment options for cancer patients.