Camrelizumab combined with paclitaxel and nedaplatin as conversion therapy for locally advanced/advanced esophageal squamous cell carcinoma: A phase II, single-arm exploratory study.

e16141 Background: This study investigated the efficacy and safety of camrelizumab in combination with paclitaxel and nedaplatin as preoperative therapy for patients with unresectable esophageal squamous cell carcinoma (ESCC). We also examined the tumor microenvironment through habitat radiomics to evaluate its potential for predicting treatment response. Methods: This single-arm, phase II study enrolled patients with clinically confirmed unresectable ESCC (staged T2-4, Nany, M0/M1). Participants received camrelizumab (200 mg) with paclitaxel (155 mg/m²) and nedaplatin (80 mg/m²) every three weeks. Efficacy was assessed every two cycles to evaluate operability. Endpoints included overall survival (OS) at 12 months, pathological complete response (pCR) rates, objective response rate (ORR), disease control rate (DCR), and disease-free survival (DFS). We also utilized retrospective clinical data as training set and the patient data of this study as test set to extract radiomic features from the tumor and its surrounding environment. Results: A total of 141 patients were enrolled, with 7 dropping out. Among the 134 patients analyzed for efficacy, the overall ORR was 56.7%, with a DCR of 98.5%. Surgical conversion rate was 48.9%. In the pathological analysis of 67 patients, 14 (20.9%) attained pCR (ypT0N0) and 37 (55.2%) achieved major pathological response (MPR). With a median follow-up time of 26.9 months, the median OS for the overall patients was 30.7 months, while the median OS for non-surgical patients was 12.8 months. The median OS for surgical patients has not been reached, with 1-year, 2-year, and 3-year OS rates at 96.7%, 83.3%, and 71.4%, respectively, significantly higher than the rates of 58.2%, 30.3%, and 22.4% for non-surgical patients. The median DFS for surgical patients has not been reached, with 1-year, 2-year, and 3-year DFS rates of 96.7%, 70.8%, and 64.7%, respectively. Safety profiles were consistent with known effects of camrelizumab, with 75.9% experiencing adverse events. Additionally, a model integrating intratumoral and peritumoral habitat radiomics with clinical variables effectively predicted pCR following conversion therapy. Conclusions: The combination of camrelizumab, paclitaxel, and nedaplatin demonstrates promising efficacy and manageable adverse effects as a conversion therapy, enhancing surgical resectability and survival outcomes without delaying surgery. Clinical trial information: ChiCTR2100046355 . Survival outcomes. pCR (n=14) Non-pCR (n=53) P value MPR (n=37) Non-MPR (n=30) P value mOS Not reached (NR) NR 0.449 NR NR 0.160 1-year OS rate 91.7% 97.9% / 96.9% 96.3% / 2-year OS rate 91.7% 81.0% / 86.9% 76.7% / 3-year OS rate 91.7% 67.5% / 76.1% 63.1% / mDFS NR NR 0.238 NR NR 0.403 1-year DFS rate 91.7% 97.9% / 96.9% 96.3% / 2-year DFS rate 91.7% 65.8% / 73.6% 64.6% / 3-year DFS rate 91.7% 59.2% / 64.4% 60.0% /