Abstract
BACKGROUND: This meta-analysis examined the risk of hepatotoxicity in patients with solid tumors who received a PD-1/PD-L1 inhibitor alone, a PD-1/PD-L1 inhibitor plus chemotherapy, or chemotherapy alone. METHODS: Potentially eligible studies were identified by searches of Embase and PubMed. All included studies were randomized controlled trials (RCTs) that examined patients with solid tumors who received a PD-1/PD-L1 inhibitor and/or chemotherapy. RESULTS: We included 20 clinical trials (11,634 patients). Thirteen trials compared PD-1/PD-L1 inhibitor monotherapy with chemotherapy. These two groups had similar risk for elevated markers of hepatotoxicity (based on analysis of all marker grades and high marker grades), although the PD-1/PD-L1 inhibitor group had an elevated relative risk (RR) of elevated aspartate aminotransferase (AST; RR = 2.13, 95% CI = 1.04 to 4.36, P = 0.04) when considering high grades alone; however, this disparity was not significant for comparisons of the pembrolizumab and nivolumab subgroups with the chemotherapy group. Compared with chemotherapy, PD-1/PD-L1 inhibitors increased the risk of all-grade hepatitis (RR = 5.85, 95% CI = 1.85 to 18.46, P < 0.01), and high-grade hepatitis (RR = 5.66, 95% CI = 1.58 to 20.27, P < 0.01). Seven other studies compared PD-1/PD-L1 inhibitor plus chemotherapy with chemotherapy alone. The combined treatment led to a higher risk for all-grade hepatitis (RR = 2.14, 95% CI = 1.29 to 3.55, P < 0.01) and high-grade hepatitis (RR = 5.24, 95%CI = 1.89 to 14.52, P < 0.01), but these groups had similar risk for all-grade and high-grade elevated markers of hepatotoxicity. CONCLUSIONS: Relative to chemotherapy alone, PD-1/PD-L1 inhibitors with or without chemotherapy increased the risk of all-grade and high-grade hepatitis, but generally did not increase the risk of elevated blood markers of hepatotoxicity.