Pembrolizumab is a humanized monoclonal antibody that blocks the interaction between PD-1 and its ligands, PD-L1 and PD-L2. By binding to the PD-1 receptor and blocking the interaction with the receptor ligands, pembrolizumab releases the PD-1 pathway–mediated inhibition of the immune response, including the antitumor immune response.
Pembrolizumab is currently indicated for the treatment of patients with unresectable or metastatic melanoma and disease progression following ipilimumab (Yervoy) and, if BRAF V600 mutation–positive, a BRAF inhibitor.
FDA Grants Breakthrough Therapy Designation
The U.S. Food and Drug Administration (FDA) has granted Breakthrough Therapy Designation to the anti–PD-1 therapy pembrolizumab (Keytruda) for the treatment of patients with epidermal growth factor receptor (EGFR) mutation–negative, and anaplastic lymphoma kinase (ALK) rearrangement–negative non–small cell lung cancer (NSCLC) that has progressed on or following platinum-based chemotherapy.
The Breakthrough Therapy designation in advanced NSCLC is supported by data from the ongoing phase IB KEYNOTE-001 study, updated findings of which were recently presented at the European Society of Medical Oncology (ESMO) 2014 Congress. ■