HanchorBio Secures Taiwan TFDA Approval for HCB303 Following U.S. FDA Clearance

HanchorBio, Inc. has announced that its subsidiary, FBD Biologics Limited, received approval from the Taiwan Food and Drug Administration (TFDA) for the Investigational New Drug application for HCB303. This follows a previous U.S. FDA clearance, authorizing the planned clinical investigation of the trispecific fusion protein in multiple jurisdictions.

Overview of HCB303 and Its Mechanism

HCB303 is an investigational, humanized trispecific fusion protein developed through HanchorBio's proprietary FBDB™ platform. Unlike conventional anti-TIGIT antibodies that primarily block inhibitory signaling, HCB303 utilizes a differentiated TIGIT-Fc ligand-trap strategy designed to bind shared ligands such as PVR/CD155 and CD112.

• Targeting CD226 Protection: The design aims to limit ligand-mediated CD226 downregulation, potentially preserving cell-surface expression.
• Multifaceted Immune Modulation: The molecule also integrates PD-L1 blockade and SIRPα-mediated CD47 checkpoint inhibition.
• Combined Immunity: It is engineered to coordinate macrophage, T-cell, and natural killer (NK) cell responses within a single molecule.

Regulatory Pathway and Global Development

The Taiwan TFDA approval was secured through an accelerated review pathway designed for multinational, multicenter clinical trials. This pathway offers a streamlined 15-day review process for eligible applications and simplifies submission requirements for qualifying first-in-human studies.

HanchorBio is preparing to advance HCB303 into a Phase 1 first-in-human, dose-escalation study (HCB303-ONC-101; NCT07859228). This trial will evaluate patients with advanced, relapsed, or refractory solid tumors who have exhausted standard treatment options.

• Study Goals: Assess safety, tolerability, pharmacokinetics, pharmacodynamics, immunogenicity, biomarkers, and preliminary antitumor activity.
• Translational Assessments: Investigate target engagement and immune modulation to inform future dose optimization.

Important Safety and Regulatory Context

It is important to note that HCB303 is an investigational agent. U.S. FDA clearance and Taiwan TFDA approval authorize clinical investigations to proceed but do not constitute marketing approval, nor do they establish the safety or efficacy of the drug. Preclinical observations and mechanistic hypotheses remain to be validated through upcoming clinical and translational studies.

Observers and stakeholders can verify the original regulatory status and trial details by reviewing public filings on the Taiwan TFDA portal or referencing clinical trial registries using identifier NCT07859228.