Multinational phase 3 trial of first-line tislelizumab plus chemotherapy for advanced/metastatic esophageal squamous cell carcinoma

The options for first-line treatemtn of advanced/metastatic esophageal squamous cell carcinoma (A/M ESCC) are limited. The multinational phase 3 RATIONALE-306) compared first-line tislelizumab (anti-PD-1) plus investigator-chosen chemotherapy versus placebo plus chemotherapy for A/M ESCC. Median overall survival was 17.2 months in the tislelizumab group versus 10.6 months in the placebo group (sHR 0.66; p<0.0001). Treatment-related adverse events were reported for 97% in the tislelizumab groups versus 96% of patients in the placebo group. Six deaths in the tislelizumab group and four deaths in the placebo group were determined to be treatment-related.The authors conclude that addition of tislelizumab to first-line chemotherapy for A/M ESCC was associated with improved OS with a manageable safety profile.