HLA associations with infliximab-induced liver injury.

Biomarkers that are able to identify patients at risk of drug-induced liver injury (DILI) after treatment with infliximab could be important in increasing the safety of infliximab use. We performed a genetic analysis to identify possible human leukocyte antigen (HLA) associations with DILI in European Caucasian users of infliximab in a retrospective study of 16 infliximab-DILI patients and 60 matched controls. In infliximab-associated liver injury, multiple potentially causal individual HLA associations were observed, as well as possible haplotypes. The strongest associated HLA allele was HLA-B39:01 (P = 0.001; odds ratio [OR] 43.6; 95% confidence interval [CI] 2.8-infinity), which always appeared with another associated allele C12:03 (P = 0.032; OR 6.1; 95% CI 0.9-47.4). Other associations were observed with HLAs DQB102:01 (P = 0.007; OR 5.7; 95% CI 1.4-24.8), DRB103:01 (P = 0.012; OR 4.9; 95% CI 1.2-20.5), and B08:01 (P = 0.048; OR 3.4; 95% CI 0.9-13.2), which also appeared together whenever present in cases. Additional associations were found with HLA-DPB110:01 (P = 0.042; OR 20.9; 95% CI 0.7-infinity) and HLA-DRB104:04 (P = 0.042; OR 20.9; 95% CI 0.7-infinity). A strong association with HLA-B39:01 was identified as a potentially causal risk factor for infliximab-induced DILI. Future work should aim to validate this finding and explore possible mechanisms through which the biologic interacts with this particular allele.