Avelumab (MSB0010718c, anti-PD-L1 IgG1) is a novel mAb that is used to inhibit the interaction between PD-1 and PD-L1, and phase I and II clinical trials highlight that it is well tolerated and show its prognostic response in Merkel cell carcinoma (MCC), NSCLC, and urothelial carcinoma (24–27). This evidence concerns the gene CD274 and Merkel cell skin cancer.