Study on Efficacy and Safety of Low-Dose Apatinib Combined with Camrelizumab and SOX Regimen as First-Line Treatment of Locally Advanced and Unresectable Gastric/Gastroesophageal Junction Cancer: A Protocol for an Open-Label, Dose Escalation and Extension Phase Ib Clinical Trial.

Background: The standard treatment for advanced gastric/gastroesophageal junction cancer (AGC/GEJC) is palliative chemotherapy combined with targeted therapy. The SOX regimen (S-1 plus oxaliplatin) is recommended as neoadjuvant or palliative first-line chemotherapy in Asian patients. Apatinib, an oral VEGFR tyrosine kinase inhibitor, is associated with additional survival benefit as third- or subsequent-line therapy.