Abstract
BACKGROUND: No data exist on the efficacy and safety of anlotinib plus camrelizumab doublet as second-line therapy for advanced esophageal squamous cell carcinoma (ESCC). Although anlotinib and the programmed death-1 (PD-1) inhibitor camrelizumab are used as treatments for ESCC, the combined use of anlotinib and camrelizumab as a second-line therapy has not been reported. Therefore, this study explored the efficacy and toxicity of anlotinib plus camrelizumab as second-line therapy for advanced ESCC. METHODS: Fifty-eight patients with advanced ESCC undergoing second-line therapy, either with anlotinib plus camrelizumab or anlotinib plus S-1, were enrolled and retrospectively analyzed at Jiangsu Province Hospital of Chinese Medicine from January 2020 to December 2021. The primary endpoint was progression-free survival (PFS), with secondary endpoints including the objective response rate (ORR), disease control rate (DCR), and assessment of toxicity. RESULTS: In patients with advanced ESCC, the anlotinib plus camrelizumab group (N = 32) exhibited longer PFS (8.00 vs. 4.53 months, P < 0.001), higher ORR (28.1 vs. 19.2%, P = 0.431), and higher DCR (87.5 vs. 65.4%, P = 0.045) than those in the anlotinib plus S-1 group (N = 26). Treatment-related adverse events (TRAEs) were predominantly grade 1/2 in both groups, with a higher incidence of grade 1/2 skin toxicity in patients treated with anlotinib plus camrelizumab (P = 0.033). Two patients (6.3%) developed grade 1/2 immune-related pneumonia. The incidence of grade 3/4 TRAEs did not differ significantly between the two groups. Multivariable Cox regression analysis identified that the drug regimen (P < 0.001), Eastern Cooperative Oncology Group performance status (P = 0.008), and differentiation grade (P = 0.008) were independent prognostic factors for PFS. CONCLUSIONS: Anlotinib plus camrelizumab exhibited promising antitumor efficacy and manageable toxicity when used as a second-line treatment for advanced ESCC.