A new clinical trials shows that pembrolizumab, a drug that utilizes the body’s immune system to target and eliminate cancer cells, appeared to reduce the risk of distant metastases for an aggressive form of skin cancer when given immediately after surgery, but did not significantly reduce the overall risk of recurrence, which was a co-primary endpoint of the trial. The randomized phase 3 trial called STAMP or EA6174, is the largest clinical study to date evaluating pembrolizumab as adjuvant therapy for Merkel cell carcinoma, an extremely aggressive disease, with fewer than half of patients surviving 5 years after diagnosis.