NCT06939439

Using ctDNA to Guide Treatment Decisions for Stage III Gastric Cancer

Circulating Tumor DNA Monitoring for Postoperative Adjuvant Therapy Decision-Making in Stage III Gastric Cancer: A Prospective, Multicenter, Randomized Controlled Phase III Clinical Trial

• Status: Active Not Recruiting
• Phase: Phase 3
• Study type: Interventional
• Enrollment: 416 (estimated)
• Sponsor: The First Affiliated Hospital with Nanjing Medical University · Academic / Other
• Sex: All
• Age: 18 Years – 80 Years
• Healthy volunteers: Not accepted

Summary

The goal of this randomized, controlled phase III clinical trial is to evaluate whether combining Tislelizumab with standard SOX chemotherapy improves disease-free survival (DFS) compared to chemotherapy alone in patients with stage III gastric or gastroesophageal junction adenocarcinoma who are ctDNA-MRD positive after surgery. The study will enroll 416 patients across multiple centers and will compare outcomes between two groups: patients receiving tislelizumab plus SOX chemotherapy and those receiving standard SOX chemotherapy alone. The primary questions to be addressed are whether the combination therapy improves 1-year DFS rates and whether it demonstrates an acceptable safety profile. Participants will provide tissue and blood samples for ctDNA-MRD testing, undergo postoperative adjuvant therapy (chemotherapy ± immunotherapy), and complete regular follow-up visits to monitor treatment response and safety. The trial will assess key outcomes, including DFS, overall survival (OS), and ctDNA clearance rates, to determine the clinical benefit and safety of tislelizumab in this population.

Conditions

• Gastric Cancer Stage III

Interventions

Type	Name	Description
DRUG	Tislelizumab + SOX Chemotherapy	The intervention in this study involves the use of tislelizumab, a humanized IgG4 anti-PD-1 monoclonal antibody, in combination with the standard SOX chemotherapy regimen for postoperative adjuvant therapy in patients with stage III gastric or gastroesophageal junction adenocarcinoma who are ctDNA-MRD positive. Tislelizumab is administered at a dose of 200 mg intravenously every 3 weeks for a total duration of 1 year, alongside 6-8 cycles of SOX chemotherapy. The SOX regimen includes oxaliplatin (130 mg/m² intravenously every 3 weeks) and tegafur, with the dose of tegafur determined based on body surface area and administered orally twice daily for 14 days every 3 weeks.
DRUG	SOX Chemotherapy	The control group will receive standard SOX chemotherapy alone, serving as an active comparator to evaluate the incremental benefit of adding tislelizumab. This design ensures a rigorous comparison while maintaining alignment with current standard-of-care practices.

Timeline

• Start date: 2024-12-01
• Primary completion: 2026-12-31
• Completion: 2029-12-31
• First posted: 2025-04-22
• Last updated: 2025-07-01

Locations

1 site across 1 country: China