Multicenter phase 3 trial of induction-concurrent chemoradiotherapy with or without sintilimab for locoregionally advanced nasopharyngeal carcinoma

The phase 3 CONTINUUM trial, at nine centers in China, evaluated addition of sintilimab (anti-PD-1) to standard induction-concurrent chemoradiotherapy for hihg-risk locoregionally advanced nasopharyngeal carcinoma. The primary endpoint was event-free survival. The median follow-up was 41.9 months. The sintilimab group had better event-free survival, both distant and locoregionally. There was no significant difference between the groups for overall survival at 3 years. Grade 3-4 events occurred in 74% of patients in the sintilimab group and 65% of patients in the standard therapy group; grade 5 events occurred in two and one patients, respectively. The authors conclude that addition of sintilimab to standard chemoradiotherapy improved event-free survival, albeit with higher but manageable adverse events. Longer follow-up is necessary to determine whether this regimen can be considered standard of care for patients with high-risk locoregionally advanced nasopharyngeal carcinoma.