KEYTRUDA® (pembrolizumab) mode of action

Prescribing Information (Great Britain) & Prescribing Information (Northern Ireland) [External links]

Prescribing Information (Great Britain) & Prescribing Information (Northern Ireland) [External links]

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KEYTRUDA exerts dual ligand blockade

KEYTRUDA is a selective monoclonal antibody that blocks the programmed cell death-1 (PD-1) protein pathway, potentiating T-cell responses, including anti-tumour responses.1,2

When functioning properly, T cells are activated and can attack tumour cells.1,2

Some tumours can evade the immune system through the PD-1 pathway. On the surface of tumour cells the dual PD-1 ligands, PD-L1 and PD-L2, bind to the PD-1 receptors on T cells to inactivate them, allowing tumour cells to evade detection.1,2

By inhibiting this process, KEYTRUDA reactivates tumour-specific cytotoxic T lymphocytes and anti-tumour immunity.1,2

PD-L1 = Programmed Cell Death Ligand-1; PD-L2 = Programmed Cell Death Ligand-2.


  1. Harvey, RD. Clin Pharm Therapeutics. 2014:92(2):214-223.
  2. KEYTRUDA Summary of Product Characteristics.

More information about KEYTRUDA

Supporting documentation

Prescribing Information (Great Britain) & Prescribing Information (Northern Ireland) 
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