Multicenter phase 3 trial of addition of serplulimab to first-line chemotherapy for advanced PD-L1 positive esophageal squamous cell carcinoma

First-line systemic therapeutic options for advanced esophageal squamous cell carcinoma (ESCC) are limited. The multicenter phase 3 ASTRUM-007 trial in China evaluated addition of serplulimab (anti-PD-1) to first-line chemotherapy for locally advanced or metastatic ESCC with a PD-L1 combined positive score (CPS) 1 or higher. Addition of serplulimab resulted in significant improvement of progression-free survival as well as overall survival among all patients (a), patients with PD-L1 CPS 1-10 (b), and patients with PD-L1 CPS 10 or higher. Grade 3 or higher treatment-related adverse events occurred in 53% of patients with serplulimab plus chemotherapy and 48% of patients with placebo plus chemotherapy. The authors conclude that addition of serplulimab to first-line chemotherapy for advanced PD-L1-positive ESCC resulted in significant improvement of PFS and OS, with a manageable safety profile.