Merkel cell carcinoma responds to immunotherapy

Overview

VIENNA – High response rates to pembrolizumab and to intratumoral delivery of plasmid interleukin-12 (IL-12) were observed among patients with advanced Merkel cell carcinoma (MCC), based on studies presented at the 2015 European Cancer Congress.

There is strong rationale for immunotherapy in MCC. For one thing, the Merkel cell polyomavirus, which is expressed in 80% of tumors, serves as a powerful antigen for stimulating an immune response. Secondly, MCC tumors often express the ligand for the programmed death protein (PD-1), creating an opportunity for PD-1 pathway blockade with PD-1 inhibitors such as pembrolizumab, according to the investigators.