Shanghai, China, May 23, 2026
Henlius Biotech has announced that the first patient has been dosed in a Phase 1 clinical trial evaluating HLX316/E-688, a potential first-in-class B7-H3–targeted sialidase fusion protein, for patients with advanced or metastatic solid tumors in China. The milestone marks a major advancement for the company’s next-generation immuno-oncology pipeline and reflects growing momentum in the development of innovative cancer therapies designed to overcome tumor immune evasion.
The clinical study, known as HLX316-FIH101, is designed to evaluate the safety, tolerability, pharmacokinetics, and preliminary anti-tumor activity of HLX316 in patients with difficult-to-treat solid tumors. Researchers believe the therapy could potentially overcome key limitations associated with existing immunotherapies by simultaneously targeting both protein-mediated and glycan-mediated immune suppression mechanisms within the tumor microenvironment.
HLX316 Targets Dual Immune Evasion Pathways
HLX316 is an engineered human sialidase fusion protein targeting B7-H3 (CD276), an immune checkpoint protein highly expressed across multiple aggressive cancers including lung, breast, colorectal, pancreatic, ovarian, and prostate tumors. High levels of B7-H3 are frequently associated with tumor progression, poor patient prognosis, and resistance to conventional therapies. Henlius stated that the therapy was specifically designed to address two major mechanisms tumors use to evade immune attack — B7-H3 overexpression and tumor hypersialylation.
According to the company, excessive sialylation on tumor cells activates inhibitory Siglec receptors on immune cells, suppressing both innate and adaptive anti-tumor immune responses. HLX316 works by enzymatically removing terminal sialic acids while concentrating its activity within B7-H3-positive tumor cells. Scientists believe this approach may help restore immune activity and improve anti-cancer responses within the tumor microenvironment. Preclinical studies demonstrated that HLX316 produced potent tumor desialylation activity with a favorable tolerability profile, supporting its advancement into human clinical testing.
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Researchers also believe the technology could potentially expand the effectiveness of immunotherapy across tumor types that currently respond poorly to existing checkpoint inhibitors. The therapy represents part of a broader shift toward next-generation immuno-oncology strategies focused on overcoming complex tumor immune resistance pathways.
Phase 1 Study Evaluates Safety and Preliminary Efficacy
The ongoing study is an open-label, first-in-human Phase 1 clinical trial that includes both dose-escalation and dose-expansion stages aimed at identifying the therapy’s maximum tolerated dose (MTD) and recommended Phase 2 dose (RP2D). Patients enrolled in the trial will receive weekly doses ranging from 1.0 mg/kg to 30.0 mg/kg.
The primary objectives include evaluating safety, dose-limiting toxicities, pharmacokinetic behavior, and preliminary anti-tumor efficacy through objective response rate assessments. Henlius stated that the trial represents an important milestone in validating glyco-immunology-based cancer therapies and could contribute to future advances in precision oncology treatment approaches.
The company noted that HLX316 originated from a strategic collaboration with Palleon Pharmaceuticals, a biotechnology company focused on glycobiology and cancer immunotherapy innovation. Palleon was co-founded from the glycobiology research of 2022 Nobel Prize-winning scientist Dr. Carolyn Bertozzi, whose work helped establish the scientific foundation for therapies targeting cell surface sialoglycans.
Henlius Expands Multi-Modal Oncology Pipeline
Henlius stated that the advancement of HLX316 reflects the company’s broader strategy to build a diversified and globally competitive oncology pipeline spanning multispecific antibodies, antibody-drug conjugates (ADCs), fusion proteins, immune cell engagers, and AI-powered drug discovery technologies. Several additional pipeline programs are simultaneously progressing through early-stage clinical development, reinforcing the company’s long-term innovation strategy.
Industry experts believe HLX316 could represent an important advancement within the emerging field of glyco-immunology, an area of cancer research focused on targeting tumor-associated glycans and immune suppression pathways. As competition intensifies within the global immuno-oncology sector, novel mechanisms such as B7-H3-directed desialylation may create new therapeutic opportunities for patients with limited treatment options.
Henlius confirmed that it will continue accelerating its Globalization 2.0 strategy, supporting international clinical development while expanding access to innovative biologics across major healthcare markets worldwide. The company aims to strengthen its position as a globally recognized biopharmaceutical innovator by advancing differentiated oncology therapies into late-stage development and commercialization.
Source: Henlius press release
