Efficacy and biomarker exploration of camrelizumab combined with apatinib in the treatment of advanced primary liver cancer: a retrospective study

This study was to explore the efficacy and safety of camrelizumab combined with apatinib in patients with advanced liver cancer. Moreover, the relationship between peripheral blood parameters and tumor response rate was also investigated. Patients with unresectable or recurrent primary liver cancer (PLC) who received treatment from July 2019 to July 2020 in the First Affiliated Hospital of Guangxi Medical University were included in this single-center retrospective study. The patients were treated with camrelizumab (200 mg, intravenous q2w) plus apatinib (250 mg, oral qd) until the occurrence of disease progression or unbearable toxicity. All the patients underwent blood routine test and detection of lactate dehydrogenase and serum albumin levels before treatment. The primary endpoints were objective response rate (ORR) and disease control rate (DCR). This study included a total of 45 patients. The overall ORR was 33.3% [95% confidence interval (CI),19.0-47.7] and the overall DCR was 57.8% (95% CI, 42.8-72.8). The ORR and DCR were higher in the first-line treatment than those in the second-line treatment (ORR: 45.5% vs. 21.7%, DCR: 63.6% vs. 52.3%). Median progression-free survival in the second-line treatment was 10.5 months (95% CI, 7.9-13.1, P = 0.022). Adverse events occurred in 39 (86.7%) patients. Grade 3/4 adverse reactions occurred in 7 (15.6%) patients. One patient (4.3%) was terminated from treatment due to adverse events. One patient (4.3%) died, which was potentially associated with adverse events. Subgroup analysis indicated that the remission rate in patients with high lymphocyte to monocyte ratio (H-LMR) was higher than that in patients with low lymphocyte to monocyte ratio (L-LMR) (56.25% vs. 25.93%, P = 0.047), and the remission rate in patients with high Prognostic Nutritional Index (H-PNI) was higher than that in patients with low Prognostic Nutritional Index (L-PNI) (66.7% vs. 26.5%, P = 0.046). Camrelizumab combined with apatinib in the treatment of PLC showed encouraging clinical efficacy, with tolerable toxicities. Levels of PNI and LMR may serve as predictors of the prognosis of advanced PLC patients who receive immunotherapy combined with targeted therapy.