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Keytruda (pembrolizumab)

Merck & Co. · FDA-approved approved Monoclonal antibody Verified Quality 98/100

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

KEYTRUDA QLEX combines pembrolizumab (PD-1 inhibitor) with berahyaluronidase alfa for enhanced subcutaneous delivery across multiple cancer indications including melanoma, NSCLC, mesothelioma, and HNSCC. The drug demonstrates clinical efficacy as monotherapy and in combination regimens, with steady-state pharmacokinetics achieved by 16 weeks and a 22-day half-life enabling convenient dosing schedules. Primary contraindication is hypersensitivity to berahyaluronidase alfa or hyaluronidase; specific populations including pediatric patients ≥12 years and those with mild-to-moderate hepatic impairment show comparable pharmacokinetics to adults. Companion diagnostics for PD-L1 expression and EGFR/ALK status are required for appropriate patient selection in NSCLC and HNSCC indications.

At a glance

Generic namepembrolizumab
SponsorMerck & Co.
Drug classMonoclonal antibody; PD-1 inhibitor
TargetPD-1 receptor
ModalityMonoclonal antibody
Therapeutic areaOncology
PhaseFDA-approved
First approval2014
Annual revenue29500

Mechanism of action

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.

Approved indications

Common side effects

Key clinical trials

Patents

PatentExpiryType
Biologic Exclusivity

Primary sources

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SourceUsed for
FDA labelMechanism, indications, dosing, boxed warnings, drug interactions
ClinicalTrials.govTrial enrolment, design, endpoints, results
FDA Orange BookPatents + exclusivity
SEC EDGARRevenue + earnings

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