US regulators are undertaking a priority review of MSD’s Keytruda for the treatment of adult and paediatric patients with recurrent locally advanced or metastatic Merkel cell carcinoma (MCC).

This application is based on data from the Phase II KEYNOTE-017 trial, which showed an objective response rate of 56% at 14.9 months in patients taking the immunotherapy, including a 24% complete response rate and a 32% partial response rate.

“Merkel cell carcinoma, a rare type of skin cancer, is an aggressive and fast-growing disease that has been associated with mortality rates higher than other types of skin cancer, including melanoma,” said Dr Scot Ebbinghaus, vice president, clinical research, Merck Research Laboratories.

“KEYNOTE-017 represents the longest observation to date of patients with advanced Merkel cell carcinoma receiving anti-PD-1 therapy in the first-line setting, and demonstrated durable tumor control in these patients.”

The FDA has set an action date of December 28 this year.