RecruitingDrug trialClinical Trial Evaluating TQB6411 Injection in Participant s With Esophageal CancerThe Phase Ib stage of this study primarily aims to evaluate the tolerance and safety of TQB6411 Injection in participants with recurrent or metastatic Esophageal cancer who have previously failed treatment with PD-1/PD-L1 monoclonal antibodies combined with platinum-based chemotherapy. The Phase II stage primarily aims to evaluate the efficacy of TQB6411 Injection in this same participants population.