Posted: Thursday, October 13, 2022
Jürgen C. Becker, MD, PhD, of the University of Duisburg-Essen, Germany, and colleagues conducted a study to investigate the safety and efficacy of adjuvant PD-1 blockade by immune checkpoint inhibition with nivolumab versus observation in patients with completely resected Merkel cell carcinoma. The preplanned interim disease-free survival analysis of the multicenter phase II ADMEC-O trial, which was presented during the European Society for Medical Oncology (ESMO) Congress 2022 (Abstract 787O), may address an unmet clinical need in a population with no systemic standard-of-care options.
“In this first randomized trial for Merkel cell carcinoma, a hazard ratio for disease-free survival of 0.56 in favor of nivolumab was observed at a median follow-up of 2 years, suggesting clinical benefit in this unmet medical need,” the investigators reported. “Remarkably, the spontaneous course of Merkel cell carcinoma was considerably better than historical data would have suggested.”
Between March 2017 and August 2020, patients were randomly assigned in a 2:1 ratio to receive 480 mg of nivolumab every 4 weeks for up to 1 year (n = 118) or observation (n = 61). They were stratified based on stage of disease (American Joint Committee on Cancer [AJCC] I/II vs. III/IV), age (< 65 vs. ≥ 65 years), and gender.
With a median follow-up of 24.3 months, the investigators reported that all patients had ended treatment. At 12 and 24 months, the disease-free survival rates were 87.9% and 86.9% with nivolumab and 78.5% and 74.3% with observation. The study remains immature for overall survival analysis.
Treatment was found to be well tolerated, with 41% of patients who received nivolumab and 31% of those who received observation experiencing grade 3 or 4 adverse events; 5% of patients discontinued treatment because of adverse events. No treatment-related deaths were reported in this population.
Disclosure: For full disclosures of the study authors, visit cslide.ctimeetingtech.com.