Burden of grade 3 or 4 liver injury associated with immune checkpoint inhibitors

Background &amp; Aims: There is concern about the burden of liver injury in patients with cancer exposed to immune checkpoints inhibitors (ICIs). Methods: In a retrospective cohort study, we evaluated the likelihood of grade 3/4 liver injury, of grade 3/4 cholestatic liver injury, and of liver failure, as per the Common Terminology Criteria for Adverse Events (CTCAE) version 5, following treatment with ICIs. We compared these occurrences with a group of cancer patients who were propensity-matched and treated with conventional chemotherapy. For all ICI patients experiencing grade 3/4 liver injury, we conducted a causality assessment using the RUCAM method and examined patient outcomes. Results: Among 952 patients (median [IQR] age 66 [57–73] years, 64% males) who were treated with ICI between January 1, 2015, and December 31, 2019, a total of 86 (9%) progressed to grade 3/4 liver injury, and liver failure was not observed. Anti-PD-(L)1/anti-CTLA-4 antibodies combinations (adjusted hazard ratio 3.36 [95% CI: 1.67–6.79]; p <0.001), and chronic hepatitis B (adjusted hazard ratio 5.48 [95% CI: 1.62–18.5]; p = 0.006], were independent risk factors. Liver injury was attributed to ICI treatment in 19 (2.0%) patients. Patients with ICI toxicity typically presented with granulomatous hepatitis or cholangiocyte inflammation. ICI withdrawal was associated with cancer progression and mortality. Re-introduction of ICI was not associated with recurrent grade 3/4 liver injury. Compared with matched patients treated with conventional, non-ICI-based chemotherapy, anti-PD-(L)1/anti-CTLA-4 combinations (p