The 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.
Participants voluntarily participate in this study, sign the informed consent form, and demonstrate good compliance.
Age between 18 and 75 years old (inclusive)
Eastern Cooperative Oncology Group (ECOG) score of 0-1
Expected survival >12 weeks
Current or History of Other Malignancies
Participants with any condition that may compromise venous access for drug administration or blood sampling are excluded.
Participants with prior treatment-related adverse reactions that have not recovered to ≤ Grade 1 per CTCAE v5.0 criteria.
Major surgical procedure or significant traumatic injury within 4 weeks prior to first dose, Scheduled major surgery during the study intervention period, Non-healing wound, ulcer, or bone fracture at screening