Using ctDNA to Guide Treatment Decisions for Stage III Gastric Cancer

NCT ID: NCT06939439

Last Updated: 2025-07-01

Basic Information

• Recruitment Status: ACTIVE_NOT_RECRUITING
• Clinical Phase: PHASE3
• Total Enrollment: 416 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2024-12-01
• Study Completion Date: 2029-12-31

Brief 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

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: NONE

Study Groups

Tislelizumab + SOX Chemotherapy

Patients in this group will receive tislelizumab (200 mg IV every 3 weeks for 1 year) in combination with SOX chemotherapy (oxaliplatin 130 mg/m² IV every 3 weeks and tegafur based on body surface area orally twice daily for 14 days every 3 weeks).

Group Type: EXPERIMENTAL

Tislelizumab + SOX Chemotherapy

Intervention Type: DRUG

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.

SOX Chemotherapy Alone

Patients in this group will receive standard SOX chemotherapy alone (oxaliplatin 130 mg/m² IV every 3 weeks and tegafur based on body surface area orally twice daily for 14 days every 3 weeks).

Group Type: ACTIVE_COMPARATOR

SOX Chemotherapy

Intervention Type: DRUG

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.

Interventions

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.

Intervention Type: 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.

Intervention Type: DRUG

Eligibility Criteria

Inclusion Criteria

Histological or Cytological Confirmation: Patients must have a confirmed diagnosis of stage III gastric or gastroesophageal junction adenocarcinoma (according to the 8th edition of the American Joint Committee on Cancer (AJCC) staging system) based on histological or cytological examination.

Surgical Resection: Patients must have undergone D2 or more extensive lymph node dissection surgery, with available tumor tissue samples. Patients who received neoadjuvant therapy prior to surgery are excluded.

Age: Patients must be between 18 and 75 years of age. General Condition: Patients must have an Eastern Cooperative Oncology Group (ECOG) performance status of 0-1.

Informed Consent: Patients must be able to understand the study protocol and voluntarily participate in the study, providing written informed consent.

Compliance: Patients must demonstrate good compliance, willingness to adhere to the treatment regimen specified in the study protocol, and ability to provide blood samples at designated time points.

Clinical Data: Patients must have complete imaging and pathological clinical data available.

Life Expectancy: Patients must have an expected survival of more than 3 months. Organ and Marrow Function: Patients must have adequate organ and bone marrow function.

Exclusion Criteria

Inability to Confirm Diagnosis: Patients who cannot be confirmed as having primary stage III gastric or gastroesophageal junction adenocarcinoma through histological or cytological examination.

Inability to Receive Treatment: Patients who are unable to receive immune checkpoint inhibitors or SOX chemotherapy.

Inability to Comply with Follow-up: Patients who are unable to adhere to the predetermined clinical follow-up schedule.

Inability to Accept Study Protocol: Patients who cannot accept the treatment regimen specified in the study protocol.

Inability to Provide Efficacy Assessment: Patients who cannot undergo or provide designated efficacy assessment methods such as CT scans.

Autoimmune Diseases: Patients with a history of autoimmune diseases. Psychiatric or Substance Abuse Issues: Patients with a history of substance abuse that cannot be discontinued or those with psychiatric disorders, or any severe and/or uncontrolled medical conditions.

Severe Comorbidities: Patients with any severe comorbidities that, in the investigator's judgment, may jeopardize patient safety or completion of the study.

Pregnancy or Breastfeeding: Pregnant or breastfeeding women. Prior Neoadjuvant Therapy: Patients who received neoadjuvant therapy prior to surgery or intraoperative chemotherapy infusion.

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 80 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

First Affiliated Hospital of Suzhou Medical College

OTHER

Sponsor Role: collaborator

The Affiliated Hospital of Xuzhou Medical University

OTHER

Sponsor Role: collaborator

Nanjing Gaochun People's Hospital

OTHER

Sponsor Role: collaborator

The Affiliated Jiangning Hospital of Nanjing Medical University

OTHER

Sponsor Role: collaborator

The First Affiliated Hospital with Nanjing Medical University

OTHER

Sponsor Role: lead

Responsible Party

Hao Xu

Professor

Responsibility Role: PRINCIPAL_INVESTIGATOR

Locations

First Affiliated Hospital with Nanjing Medical Unviersity

Nanjing, Jiangsu, China

Countries

China

Other Identifiers

CLAYMORE

Identifier Type: -

Identifier Source: org_study_id