This study is a prospective, randomized controlled, phase III multicenter trial. Its objectives are to explore the stratified application of consolidation immunotherapy after chemoimmunotherapy induction plus concurrent chemoradiotherapy, identify the potential beneficiary population of consolidation immunotherapy, and evaluate the efficacy and safety of consolidation immunotherapy.
The main participants are patients with unresectable locally advanced esophageal squamous cell carcinoma who have undergone 2-4 cycles of chemoimmunotherapy induction followed by concurrent chemoradiotherapy. Imaging assessment should be completed within 1-84 days after the end of chemoradiotherapy. Eligible patients meeting the inclusion and exclusion criteria will be divided into the CR/PR cohort and SD cohort based on treatment response, and receive the following treatments respectively:
CR/PR cohort: Patients with a response assessment of CR (Complete Response) or PR (Partial Response) will be randomly assigned at a 1:1 ratio to:
Toripalimab monotherapy maintenance group (Group A1) vs. Observation group (Group A2) (116 patients vs. 116 patients)
SD cohort: Patients with a response assessment of SD (Stable Disease) will be randomly assigned at a 1:1 ratio to:
Toripalimab monotherapy maintenance group (Group B1) vs. Observation group (Group B2) (54 patients vs. 54 patients) The medication dosage is as follows: Toripalimab 240mg, intravenous infusion on Day 1, every 3 weeks (Q3W). A total of 3 treatment cycles will be administered. Subsequent treatment continuation will be determined by the patient. If continued, treatment will proceed until the occurrence of disease progression (radiological progression confirmed by RECIST v1.1), intolerable toxicity, initiation of new antitumor therapy, voluntary withdrawal of the subject from the study, or the investigator's judgment that the subject needs to withdraw. The maximum duration of medication is 1 year.
Patients voluntarily participate in this study, signed informed consent, good compliance with follow-up;
Aged 18-75 years (inclusive), male or female;
Clinically staged II-IVa unresectable (AJCC 8th ed.: cT1N2-3M0/cT2-4bN0-3M0) or IVb (supraclavicular lymph node metastasis only); the patient had no disease progression after 2-4 cycles of chemo-immunotherapy induction combined with concurrent chemoradiotherapy (CCRT). Patients receiving CCRT must meet the following criteria: Patients with inoperable tumors must have received at least 2 cycles of weekly regimen or 1 cycle of 3-week platinum-based chemotherapy combined with radical radiotherapy (50-64 Gy) and have no evidence of radiographic disease progression (according to RECISTv1.1) as compared to before and after radical concurrent chemoradiation;
ECOG PS 0-1;
Any unresolved NCI CTCAE ≥ grade 2 toxicity following prior chemoradiotherapy. Patients with irreversible and controllable hearing loss are eligible;
Small cell carcinoma, adenocarcinoma, or mixed carcinoma components in histology;
Grade ≥ 2 peripheral neuropathy based on NCI CTCAEv5.0 criteria
Found to have a higher risk of esophageal fistula by clinical assessment or imaging studies, such as a past history or related symptoms of esophageal fistula, or infiltration of the primary tumor into the great vessels or trachea;