Shanghai, China, December 29, 2025—Shanghai Henlius Biotech, Inc. (2696.HK) today announced that the first patient has been dosed in a first in human phase 1 clinical trial for HLX37(HLX37-FIH101), an innovative recombinant humanized anti-PD-L1 and anti-VEGF bispecific antibody independently developed by the company. This milestone marks the initiation of clinical development for HLX37 in patients with advanced/metastatic solid tumors in China.
The mechanism of action of HLX37 integrates two therapeutic pathways: (1) Blocking PD-1/PD-L1 interaction: by inhibiting the binding of PD-L1 on tumor cells to the PD-1 receptor on immune cells (e.g., T cells), it reverses tumor-induced immunosuppression and restores T cell-mediated anti-tumor activity; (2) Anti-angiogenic pathway: by neutralizing VEGF, it suppresses tumor angiogenesis, thereby cutting off the blood supply essential for tumor growth and metastasis. By specifically binding to PD-L1 on tumor cells, HLX37 achieves enhanced enrichment of the bispecific antibody within the tumor microenvironment, leading to superior efficacy compared to the combination of anti-PD-L1 and anti-VEGF monoclonal antibodies. Preclinical studies indicate that HLX37 has strong anti-tumor activity and favorable safety profile, with enhanced tumor enrichment, indicating its broad therapeutic potential across multiple tumor types. These findings were first presented at the 2025 American Association for Cancer Research (AACR) Annual Meeting [1].
HLX37 is a bispecific antibody combining an anti-VEGF mAb with an anti-PD-L1 VHH domain, derived from Henlius’s synthetic humanized llama VHH library. The company has established an integrated antibody discovery-to-manufacturing platform that serves as the core engine for differentiated antibody-based therapeutics. The platform focuses on the development of function-blocking antibodies and features a robust, diversified VHH libraries encompassing natural, synthetic humanized, and immunized llama VHHs. It enables efficient selection of high-affinity and highly specific VHHs and scFvs against diverse targets, providing a solid foundation for the design of next-generation multispecific antibodies. Furthermore, leveraging deep industry expertise, Henlius has systematically developed a comprehensive discovery and characterization database for multispecific antibodies—including bispecific, trispecific, and tetraspecific formats—as well as antibody fusion proteins. This database supports rational design and functional profiling, enhancing the probability of success development of complex antibody therapeutics. Built upon this platform, the company has advanced 10 products to marketing approval while fostering a pipeline of 19 clinical-stage assets with over 30 clinical studies ongoing, covering mAbs, ADCs, fusion proteins, and biosimilars. Leveraging its end-to-end capabilities and a validated, scalable CMC system, the company accelerates the translation of high-potential candidates into high-quality clinical and commercial products.
By strategically prioritizing solid tumor domain as a core therapeutic area, Henlius continues to uphold its patient-centric mission, accelerating differentiated innovation to address unmet medical needs and delivering high-quality, affordable therapies to tumor patients worldwide.
About HLX37-FIH101
HLX37-FIH101 is an open-label, first-in-human Phase I clinical trial evaluating the safety, tolerability, pharmacokinetic (PK) profiles, and preliminary efficacy of HLX37 in subjects with advanced/metastatic solid tumors. The study consists of two phases: Phase Ia dose escalation (comprising monotherapy and combination therapy) and Phase Ib dose expansion. The Phase Ia monotherapy arm is conducted in subjects with advanced solid tumors, evaluating 6 dose levels ranging from 1.0 mg/kg to 45.0 mg/kg (administered Q3W); the combination therapy arm will explore different doses of HLX37 in combination with pemetrexed or albumin-bound paclitaxel/paclitaxel and carboplatin in subjects with advanced non-small cell lung cancer (NSCLC). The dosing regimen and tumor types for Phase Ib will be determined based on the results of Phase Ia. The primary endpoints aim to evaluate the incidence of dose-limiting toxicity (DLT) to determine the maximum tolerated dose (MTD) and the recommended Phase II dose (RP2D) for both monotherapy and combination therapy. Secondary endpoints include safety indicators such as adverse events, PK parameters, and immunogenicity, as well as efficacy indicators including objective response rate (ORR), progression-free survival (PFS), and overall survival (OS), alongside the exploration of potential predictive biomarkers.