Efficacy and safety of camrelizumab in combination with trastuzumab and chemotherapy as the first-line treatment for patients with HER2-positive advanced gastric cancer

BACKGROUND

Trastuzumab plus chemotherapy is the standard-of-care (SoC) first-line therapy for HER2-positive advanced gastric cancer. Combining PD-1 antibody with SoC first-line therapy showed encouraging results in the KEYNOTE-811 study. The retrospective study aims to evaluate the efficacy and safety of SoC vs. SoC plus camrelizumab (PD-1 antibody) as a first-line treatment for HER2-positive advanced gastric cancer in a real-world setting.

METHODS

This study included 41 patients with HER2-positive advanced gastric cancer who received SoC or SoC plus camrelizumab from June 2017 to December 2020. The endpoints were objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), overall survival (OS), and safety.

RESULTS

Thirteen patients received SoC (SoC group) and 28 patients received SoC plus camrelizumab (camrelizumab group). As of December 2020, the median follow-up time was 10.0 months. In the camrelizumab and SoC groups, the ORRs were 75.0% and 46.2% (P=0.032), respectively. The DCR was 96.4% in the camrelizumab group and 69.2% in the SoC group (P=0.003). The median OS was 18.4 in the camrelizumab group and 13.2 months in the SoC group [hazard ratio (HR) =0.343; 95% confidence interval (CI): 0.151-0.783; P=0.008]. The median PFS was 3.78 in the camrelizumab group and 1.74 months in the SoC group (HR =0.416; 95% CI: 0.186-0.932; P=0.027). In the HER2 subgroups in the camrelizumab group, the median PFS of immunohistochemistry (IHC) 3+ vs. IHC 2+ fluorescence in situ hybridization (FISH) was 11.3 vs. 9.0 months (HR =1.684; 95% CI: 0.710-3.994; P=0.047). The incidence rates of reactive cutaneous capillary endothelial proliferation (RCCEP) (P<0.001), abnormal liver function (P=0.040), and hypothyroidism (P=0.039) between the two groups were significantly different. RCCEP and hypothyroidism were considered to be related to camrelizumab.

CONCLUSIONS

First-line treatment with camrelizumab combined with SoC showed significant clinical benefits and good tolerance compared with SoC for HER2-positive advanced gastric cancer.