Camrelizumab in combination with preoperative chemotherapy for locally advanced esophageal squamous cell carcinoma: A single-arm, open-label, phase II study.

Abstract

222 Background:At present, esophageal cell carcinoma (ESCC) has a dismal prognosis with huge unmet clinical needs. With the potential benefit of combining PD-1 inhibitor with neoadjuvant chemotherapy (nCT), we conducted a phase II trial to assess the efficacy and safety of Camrelizumab (anti-PD-1 antibody) plus nCT for locally advanced ESCC. Methods:26 patients (pts) with histologically confirmed stage Ⅱ/Ⅲ/Ⅳa (cT2-4aN0-3M0) ESCC were enrolled from February 2020 to September 2020.The study was divided into two stages, stage1: we administered 1 cycle of Camrelizumab for induction therapy (200 mg q2 weeks); stage2: pts received 2 cycles of Camrelizumab (200 mg every 3 weeks) plus docetaxel and nedaplatin, followed by surgery within 4~6 weeks after neoadjuvant therapy completion. Primary endpoint was major pathologic response (MPR). Secondary endpoints included pathologic complete response (pCR), R0 resection rate, disease-free survival (DFS) and overall survival (OS). In total 40 pts will be enrolled. Results:At the cutoff date of Sep 22, 2020, 26 eligible pts were enrolled (65% males, median age 63), neoadjuvant treatment was completed in 17 pts and is ongoing in 7 pts. Thus far 12 out of 17 pts were resected, 5 pts are planned to undergo surgery, 1 pt had interval metastases preoperatively, 1 pt declined surgery. All patients underwent an R0 resection. Postoperative pathology showed that T stage decreased in 10 pts with 83% reduction rate. 5 pts (42%) reached major pathologic response, 3 pts (25%) reached pathologic complete response, the others maintained stable disease (33%). No grade 3 immunotherapy related AEs were observed, no surgery related mortality. The most common AEs (all grade, grade≥3) were anemia (31%, 3%), leukopenia (7%, 0%), neutrophil (3%,0%), hypoalbuminemia (21%, 0%), hematochezia (14%, 0%), fatigue (10%, 0%) and thyroid dysfunction (24%, 0% ). Date for median PFS and OS were not matured. Conclusions:Camrelizumab in combination with preoperative chemotherapy followed by surgery for locally advanced ESCC showed promising downstaging effect and MPR with good tolerance, and its efficacy and safety could be further studied in later trials. Clinical trial information: NCT03917966.