Efficacy and safety of camrelizumab combined with oxaliplatin and S-1 as neoadjuvant treatment in locally advanced gastric or gastroesophageal junction cancer: A phase II, single-arm study.

Purpose: In the present study, we aimed to evaluate the efficacy and safety of camrelizumab combined with oxaliplatin plus S-1 in patients with resectable gastric or gastroesophageal junction cancer.

Methods: In this single-arm, phase II clinical trial, patients with locally advanced gastric or gastroesophageal junction adenocarcinoma were enrolled to receive three cycles of neoadjuvant camrelizumab and oxaliplatin plus S-1 every 3 weeks, followed by surgical resection and adjuvant therapy with the same regimen. The primary endpoint was pathological complete response (pCR) (ypT0) rate and secondary endpoints were R0 resection rate, total pCR (tpCR, ypT0N0) rate, major pathological response (MPR) rate, downstaging, objective response rate (ORR), disease control rate (DCR), event-free survival (EFS), overall survival (OS), and safety.

Results: Between September, 2020 and January, 2022, a total of 29 patients were enrolled in the present study, all of whom completed neoadjuvant therapy and underwent surgery. Three (10.3%) (95% CI: 2.2-27.4) patients achieved pCR as well as tpCR, 20 (69.0%) patients had MPR and 28 (96.6%) patients achieved R0 resection. Treatment-emergent adverse events (AEs) of any grade were observed in 24 (82.8%) patients. Immune-related adverse events of any grade were reported in 13 (44.8%) patients, whereas no grade 3 or higher adverse events occurred.

Conclusion: The neoadjuvant therapy with camrelizumab in combination with oxaliplatin and S-1 showed a modest pCR rate, and favorable MPR rate and safety profile in patients with gastric or gastroesophageal junction cancer.