Retifanlimab: a breakthrough for the management of Merkel cell carcinoma

Merkel cell carcinoma (MCC) is a rare, highly metastatic cutaneous neuroendocrine cancer originating from specialized Merkel cells, which are responsible for touch sensation in the skin. It is characterized by a firm, rapidly expanding nodule on sun-exposed skin areas, especially the head and neck. It has a high mortality rate, with reported overall survival rates ranging from 14% for distant disease to 51% for local disease. In March 2023, retifanlimab (Zynyz) received accelerated U.S. Food and Drug Administration (FDA) approval for treating adults with metastatic or recurrent locally advanced MCC. This drug offers a first-line response against MCC by improving the body’s immune response against cancer cells. This article aims to provide updated guidelines on the properties, dosing, and mechanism of action while discussing its use for the management of adults.