Source: www.cancertherapyadvisor.com Author: Debra Hughes, MS Pembrolizumab immunotherapy is effective for patients with recurrent or metastatic squamous cell carcinoma of the head and neck (SCCHN), results of the KEYNOTE-012 trial presented at the 2015 American Society of Clinical Oncology (ASCO) Annual Meeting have shown. At a fixed dose of 200 mg intravenously every 3 weeks, pembrolizumab “was well tolerated and demonstrated a clinically meaningful overall response rate of 24.8% in patients with recurrent/metastatic SCCHN,” reported Tanguy Y. Seiwert, MD, an assistant professor of medicine, and associate HNC program leader at The University of Chicago in Chicago, IL. However, “it is important to note that response rate may underestimate the rate of benefit in patients, and ultimately we need to assess survival,” said Dr. Seiwert in an ASCO press release. “We know from other diseases where the experience with immunotherapy is larger, that patients who have disease stabilization or even initially experience disease progression upon receiving immunotherapy ultimately may derive significant benefit that can translate into longer survival.” Pembrolizumab (MK-3475), a humanized monoclonal antibody that blocks interaction of PD-1 with its ligands, PD-L1 and PD-L2, promotes activity of tumor-specific effector T cells. Previously, the KEYNOTE 012 study had demonstrated clinical activity of pembrolizumab 10 mg/kg every 2 weeks in patients with recurrent/metastatic SCCHN enriched for PD-L1–positive tumors. Response rate was 20%. Dr. Seiwert reported on the study's larger SCCHN expansion cohort, irrespective of PD-L1 expression or HPV status, using a 3-weekly fixed dose. The primary end point was overall response rate [...]