Camrelizumab in combination with fluorouracil or taxol plus platinum chemotherapy as first-line treatment of esophageal squamous cell carcinoma: A multicenter, open-label, prospective cohort study.

e16084 Background: The introduction of immune checkpoint inhibitors (ICIs) after chemotherapy and targeted therapy has altered the treatment pattern of esophageal squamous cell carcinoma (ESCC). However, using ICIs alone results in a poor response rate. Fortunately, fundamental research indicates that chemotherapy might trigger immunogenic death of tumor cells by releasing tumor antigens, hence eliminating immune system repression of tumor cells. On this basis, a number of clinical studies, including KEYNOTE-590, CheckmMate-648, ORIENT-15, and ESCORT-1st, on the first-line treatment of ESCC with ICIs coupled with chemotherapy, including fluorouracil or taxol and platinum (PF or TP), were conducted and yielded favorable results. However, the advantage of safety and effectiveness of ICIs combination with PF and TP in Chinese ESCC remains unknown. Furthermore, since the southeast part of Shanxi province has a high prevalence of esophageal cancer, the geographical features of ESCC patients will be examined. Methods: Camrelizumab was maintained after 6 cycles of camrelizumab in combination with PF or TP chemotherapy. From May 2020 to February 2022, our study has included 40 locally progressed and advanced ESCC patients. Camrelizumab was administered in combination with PF to 11 patients and TP to 29 patients. Every 6 weeks, efficacy was examined using RECIST 1.1, and 33 patients were evaluated. This research was registered with the Chinese Clinical Trials Registry (ChiCTR2000037942). Results: The median treatment time was 5.8m. 82.5% (33/40) patients were availably evaluated. The objective response rate (ORR) was 72.7% (24/33) and the disease control rate (DCR) was 97.0% (32/33). There is no statistically significant difference in ORR ( p=0.1779) and DCR ( p=0.1005) between PF and TP (55.6% vs 79.2%, 88.9% vs 100%) regimens. At this moment, mPFS has not been achieved. The most common adverse events (AEs) were anemia (22.5%, 9/40), lymphocytopenia (15%, 6/40), neutropenia(15%, 6/40), reactive cutaneous capillary endothelial proliferation (RCCEP) (12.5%, 5/40) and fatigue (7.5%, 3/40). Thrombocytopenia (2.5%, 1/40), neutropenia (2.5%, 1/40) and leukopenia (2.5%, 1/40) were the most common grade 3 or 4 toxicities The most frequently reported immune-related AEs were RCCEP (12.5%, 5/40) and hypothyroidism (7.5%, 3/40). There were no new significant adverse events. Conclusions: Camrelizumab in combination with chemotherapy is a promising regimen with good tolerability in the first-line treatment of ESCC. Compared with FP, TP had more therapeutic advantages, But the result is a stage summary, and further observation is needed. Clinical trial information: ChiCTR2000037942. [Table: see text]