Study of Hypofractionated Radiotherapy with PD-1 Inhibitor and Chemotherapy as Neoadjuvant Treatment for Locally Advanced Resectable Gastroesophageal Junction Adenocarcinoma

What this Trial Is About

Researchers are evaluating the safety and effectiveness of combining hypofractionated radiotherapy with immunochemotherapy as a neoadjuvant treatment for patients with locally advanced, resectable adenocarcinoma of the gastroesophageal junction GEJA. This study aims to determine if adding radiotherapy to the PD-1 inhibitor Serplulimab and chemotherapy TS regimen improves the rate of complete pathological response compared to immunochemotherapy alone. The study is conducted in Phase Ib and Phase II stages, focusing on this specific cancer type and treatment approach. In Phase Ib, participants receive hypofractionated radiotherapy at one of three dose levels given in 5 fractions, alongside immunochemotherapy with Serplulimab 300 mg IV on Day 1 every 3 weeks and the TS regimen paclitaxel IV on Day 1 plus oral S-1 twice daily for 14 days followed by 7 days off. The recommended radiotherapy dose from Phase Ib will be used in Phase II. The trial has two groups one receiving combined radiotherapy and immunochemotherapy, and the other receiving immunochemotherapy alone. Participants will undergo assessments including safety and tolerability within 3 months after radiotherapy, pathological complete response approximately 2 weeks post-surgery, and additional outcomes such as surgical resection rates, response rates before surgery, disease-free and overall survival up to 3 years, adverse event monitoring, and quality of life questionnaires. Follow-up includes evaluations at various time points during treatment cycles and after surgery, with study participation lasting several years to monitor long-term outcomes.

Hypofractionated Radiotherapy Plus Immunochemotherapy for Neoadjuvant Treatment of Gastroesophageal Junction Adenocarcinoma