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Keytruda — mechanism of action

pembrolizumab · Merck & Co.

Pembrolizumab blocks PD-1 receptor, releasing immune inhibition and enhancing anti-tumor T-cell response.

How Keytruda works

Pembrolizumab blocks PD-1 receptor, releasing immune inhibition and enhancing anti-tumor T-cell response.

Detailed mechanism

Pembrolizumab is a monoclonal antibody that binds to the PD-1 receptor on T cells and blocks its interaction with PD-L1 and PD-L2 ligands. This blockade releases PD-1 pathway-mediated inhibition of the immune response, including anti-tumor immunity. Upregulation of PD-1 ligands occurs in some tumors and normally contributes to inhibition of active T-cell immune surveillance; pembrolizumab reverses this mechanism. Berahyaluronidase alfa is an endoglycosidase variant of human hyaluronidase PH20 that temporarily and locally breaks down hyaluronan in the subcutaneous tissue extracellular matrix. This increases tissue permeability to facilitate drug delivery. The effects are reversible, with tissue permeability restored within 24 to 48 hours. In preclinical models, blocking PD-1 activity decreased tumor growth. Combination treatment with a PD-1 blocking antibody and lenvatinib kinase inhibitor decreased tumor-associated macrophages, increased activated cytotoxic T cells, and reduced tumor growth compared to either treatment alone.

Molecular targetPD-1 receptor
Drug classMonoclonal antibody; PD-1 inhibitor
ModalityMonoclonal antibody

See also

Primary sources · FDA · ClinicalTrials.gov · EMA · SEC EDGAR · ChEMBL · Wikidata · full sourcing