PD-1 inhibition in advanced Merkel-cell carcinoma

Overview

Patients with Merkel-cell carcinoma, a rare type of skin cancer that develops in the top layer of the skin in Merkel cells, could be treated with immunotherapy, new research suggests. Paul Nghiem (Fred Hutchinson Cancer Research Center and University of Washington, Seattle, WA, USA) and colleagues treated 26 patients with advanced Merkel-cell carcinoma, who had received no previous systemic therapy, with pembrolizumab (an anti-PD-1 agent) at a dose of 2 mg/kg every 3 weeks. 26 patients received at least one dose of pembrolizumab and 25 underwent at least one evaluation during treatment; 14 (56%, 95% CI 35–76) of these patients achieved an objective response. Of these, four patients had a complete response and 10 had a partial response, which ranged in duration from at least 2·2 months to at least 9·7 months. Progression-free survival at 6 months was 67% (95% CI 49–86). Grade 3–4 treatment-related adverse events were noted in four (15%) of the 26 patients. Nghiem told The Lancet Oncology, “Merkel-cell carcinoma is a disease for which no therapies have been approved and for which chemotherapy often produces only transient responses (in about 55% of cases).