The goal of this randomized, double-blind, multi-regional phase 3 study of cadonilimab combined with chemotherapy versus chemotherapy in combination with or without nivolumab for the first-line treatment of participants with HER2-negative, previously untreated, unresectable or metastatic gastric or gastroesophageal junction adenocarcinoma trial is to compare OS between cadonilimab combined with chemotherapy and chemotherapy in combination with or without nivolumab in the ITT population.
Able to provide written informed consent and can understand and comply with the requirements of the study.
Histopathologically-confirmed diagnosis of locally advanced unresectable or metastatic G/GEJ adenocarcinoma.
No prior systemic therapy for locally advanced unresectable or metastatic G/GEJ adenocarcinoma. NOTE: For participants who have received prior neoadjuvant/adjuvant therapy for curative intent, the time between disease progression and last treatment should be at least 6 months.
ECOG PS of 0 or 1 within 3 days prior to randomization.
Histopathologically confirmed other pathological types, such as squamous cell carcinoma, sarcoma or undifferentiated carcinoma.
Known HER2 positive. Be HER2-positive defined as either IHC 3+ or IHC 2+ in combination with ISH+ (or FISH).
Participants with active central nervous system (CNS) metastases and/or carcinomatous meningitis. Participants with previously treated brain metastases may participate provided they are radiologically stable (i.e., without evidence of progression) for at least 4 weeks by repeat imaging (note that the repeat imaging should be performed during study screening), clinically stable and without requirement of steroid treatment for at least 14 days prior to first dose of study intervention.
Presence of clinically symptomatic pleural effusion, pericardial effusion, or ascites requiring frequent drainage (≥ 1 time/month).
Parallel
Cadonilimab
DrugAnti-PD-1/ CTLA-4 tetrameric bispecific antibody
CAPOX regimen
DrugA combination treatment contains oxaliplatin and capecitabine
Nivolumab
DrugAnti-PD-1 monoclonal antibody
Placebo
DrugPlacebo
Overall survival (OS)
Time from randomization to death from any cause
Progression-free survival(PFS)
Time from the date of randomization to the date of progressive disease or death from any cause, whichever occurs first.
Objective response rate (ORR)
Disease control rate (DCR)
Duration of response (DoR)
