Last reviewed 2026-04-23 · How we verify

HLX03

HLX03 is a monoclonal antibody that binds to and inhibits PD-L1, blocking its interaction with PD-1 and restoring anti-tumor immune responses.

HLX03 is a monoclonal antibody that binds to and inhibits PD-L1, blocking its interaction with PD-1 and restoring anti-tumor immune responses. Used for Non-small cell lung cancer, Gastric cancer, Other solid tumors (in development).

At a glance

Mechanism of action

HLX03 targets programmed death ligand 1 (PD-L1) on tumor cells and immune cells, preventing the PD-L1/PD-1 interaction that normally suppresses T-cell activation. By blocking this immune checkpoint, the drug allows cytotoxic T lymphocytes to recognize and attack cancer cells more effectively. This mechanism is similar to other PD-L1 inhibitors and is designed to enhance anti-tumor immunity across multiple cancer types.

Approved indications

• Non-small cell lung cancer
• Gastric cancer
• Other solid tumors (in development)

Common side effects

• Fatigue
• Decreased appetite
• Nausea
• Immune-related adverse events (pneumonitis, hepatitis, colitis)

Key clinical trials

• Study of Efficacy and Safety of HLX03 in Subjects With Moderate to Severe Plaque Psoriasis (PHASE3)
• Phase I Study of HLX3 vs Adalimumab in Chinese Healthy Subjects (PHASE1)

Primary sources

Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.

Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:

• HLX03 CI brief — competitive landscape report
• HLX03 updates RSS · CI watch RSS
• Shanghai Henlius Biotech portfolio CI