Neoadjuvant camrelizumab followed by concurrent camrelizumab plus chemotherapy for locally advanced esophageal squamous cell carcinoma: a single-arm, phase II study.

Background: Neoadjuvant therapy combining camrelizumab with chemotherapy has emerged as a promising approach for treating locally advanced esophageal squamous cell carcinoma (ESCC). However, the optimal strategy for integrating immunotherapy with chemotherapy remains to be fully defined. This single-arm phase II study aimed to evaluate the efficacy and safety of neoadjuvant therapy with camrelizumab induction followed by camrelizumab plus chemotherapy in locally advanced ESCC.

Methods: Patients with clinical stage cT2-4N0M0 or cTxN1-3M0 ESCC were enrolled in the study. Patients received one dose of camrelizumab (200 mg) followed by docetaxel (75 mg/m) and nedaplatin (75 mg/m) plus camrelizumab (200 mg) every 3 weeks for two cycles, and then underwent surgery within 3-4 weeks. The primary endpoint was the major pathological response (MPR) rate. The secondary endpoints included the pathological complete response (pCR) rate, R0 resection rate, downstaging rate, disease-free survival (DFS), overall survival (OS), and safety.

Results: In total, 55 patients were enrolled in the study between 16 April 2020 and 30 October 2021. Of these 55 patients, 53 (96.4%) completed neoadjuvant therapy, and 48 (87.3%) underwent surgery. The MPR rate was 77.1% [37/48, 95% confidence interval (CI): 62.7-88.0%]. The pCR (ypT0N0) rate was 39.6% (19/48, 95% CI: 25.8-54.7%). All the patients had R0 resections. Primary tumor downstaging occurred in 44 (91.7%) patients, and nodal downstaging occurred in 19 (39.6%) patients. The 2-year DFS rate was 68.9% (95% CI: 53.0-80.4%), and the 2-year OS rate was 74.7% (95% CI: 60.2-84.6%). Grade ≥3 treatment-related adverse events (TRAEs) were observed in 7 (12.7%) patients.

Conclusions: In conclusion, neoadjuvant camrelizumab followed by camrelizumab plus chemotherapy showed promising efficacy in treating locally advanced ESCC and had a manageable safety profile.