Last reviewed 2026-04-22 · How we verify

9MW2821

9MW2821 is a monoclonal antibody targeting PD-L1 to enhance anti-tumor immune responses by blocking the interaction between PD-L1 and PD-1/B7-1.

9MW2821 is a monoclonal antibody targeting PD-L1 to enhance anti-tumor immune responses by blocking the interaction between PD-L1 and PD-1/B7-1. Used for Non-small cell lung cancer, Other solid tumors (under investigation).

At a glance

Mechanism of action

This drug belongs to the immune checkpoint inhibitor class and works by binding to programmed death ligand 1 (PD-L1) on tumor cells and immune cells, preventing the suppressive signal that tumors use to evade the immune system. By blocking this interaction, the drug restores T-cell activation and proliferation, enabling the body's immune system to recognize and attack cancer cells more effectively.

Approved indications

• Non-small cell lung cancer
• Other solid tumors (under investigation)

Common side effects

• Fatigue
• Immune-related pneumonitis
• Diarrhea
• Rash
• Hepatotoxicity

Key clinical trials

• Platform Study of ADC Rechallenge in ADC-treated Metastatic Breast Cancer (PHASE2)
• A Dose Randomization Study of Bulumtatug Fuvedotin in TNBC Patients Previously Treated With ADCs (PHASE1)
• NECTAR Study: Neoadjuvant Toripalimab + 9MW2821 for Local UTUC (PHASE2)
• 9MW2821 Combined With Toripalimab in Perioperative Patients With Urothelial Cancer (PHASE2)
• JS207 Combination Therapy in Triple-negative Breast Cancer (PHASE2)
• A Clinical Study of 9MW2821 Monotherapy or Combined With Other Anticancer Therapy in Advanced Solid Tumors (PHASE1, PHASE2)
• 9MW2821 Combined With Other Antitumor Drugs in Patients With Advanced Gynecological Tumors (PHASE1, PHASE2)
• A Study to Evaluate 9MW2821 Versus Chemotherapy in Subjects With Previously Treated Locally Advanced or Metastatic Urothelial Cancer (PHASE3)

Primary sources

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