Enlisting the Immune System to Treat Skin Cancer

The FDA approved the use of an immune checkpoint inhibitor to treat certain patients with cutaneous squamous cell carcinoma. 

The U.S. Food and Drug Administration (FDA) approved pembrolizumab (Keytruda) to treat certain patients with recurrent or metastatic cutaneous squamous cell carcinoma that is not curable by surgery or radiation. 

Pembrolizumab inhibits the function of an immune checkpoint protein called PD-1. Some cancer cells hijack the PD-1 pathway to evade detection by the immune system. Immune checkpoint inhibitors—a class of cancer immunotherapeutics— prevent the cancer cells from hijacking the PD-1 pathway so the immune cells can attack and destroy the cancer cells. 

The data to investigate the efficacy of pembrolizumab for this type of skin cancer was obtained from a multicenter, multi-cohort, non-randomized, open-label trial. The data showed that 34 percent of participants had an objective response rate.

Skin cancer is the most commonly occurring cancer in the United States, with more than 5 million people diagnosed each year. Cutaneous squamous cell carcinoma is one of the main types and affects the thin, flat cells on the top layer of the epidermis, which is the skin’s outer layer.   

The FDA approval was rendered on June 24, 2020.