Safety and Efficacy of Radiotherapy Combined With Chemotherapy and SHR-1701, a PD-L1(Programmed Death-Ligand 1)/TGF-β(Transforming Growth Factor-beta) Bispecific Antibody, in the Treatment of Unresectable Locally Advanced or Metastatic Gastric Cancer
Gastric Cancer is one of the leading causes of cancer-related death worldwide, and patients with unresectable locally advanced or metastatic disease have a poor prognosis. This study aims to evaluate the safety and efficacy of radiotherapy combined with CAPOX and SHR-1701, a PD-L1/TGF-β bispecific antibody, in patients with unresectable locally advanced or metastatic gastric or gastroesophageal junction adenocarcinoma. By improving local tumor control and enhancing systemic antitumor activity, this study seeks to increase the opportunity for curative-intent resection and improve survival outcomes in patients with advance gastric cancer.
• Male or female participants aged 18 to 75 years.
• Histologically confirmed gastric adenocarcinoma or gastroesophageal junction adenocarcinoma.
• Unresectable locally advanced or metastatic gastric cancer, with primary and metastatic lesions amenable to radiotherapy (excluding patients with brain metastases or extensive metastatic disease).
• HER2-negative disease.
• ECOG performance status of 0-1.
• At least one measurable lesion according to RECIST version 1.1.
• Adequate organ function, including:
‣ Hemoglobin ≥90 g/L;
⁃ White blood cell count ≥3.5 × 10⁹/L;
⁃ Absolute neutrophil count ≥1.5 × 10⁹/L;
⁃ Platelet count ≥100 × 10⁹/L;
⁃ Serum creatinine ≤1.0 × upper limit of normal (ULN);
⁃ Blood urea nitrogen (BUN) ≤1.0 × ULN;
⁃ Alanine aminotransferase (ALT) ≤1.5 × ULN;
⁃ Aspartate aminotransferase (AST) ≤1.5 × ULN;
⁃ Alkaline phosphatase (ALP) ≤1.5 × ULN;
⁃ Total bilirubin (TBIL) ≤1.5 × ULN;
⁃ Negative urine protein;
⁃ Normal coagulation function.
• No contraindications to immunotherapy.
• No history of hypersensitivity to fluoropyrimidines or platinum-based agents.
⁃ No prior surgery, chemotherapy, immunotherapy, or other antitumor therapy for gastric or gastroesophageal junction cancer since diagnosis.
⁃ No previous radiotherapy to the intended irradiation sites.
⁃ Ability to understand and willingness to sign a written informed consent form.