The current disclosure provides for improved methods of treating patients who have received
immune checkpoint inhibitor (ICI) therapy and based on the finding that biomarkers can predict whether a subject experiencing adverse symptoms and undergoing ICI therapy is developing an irAE due to the ICI therapy or due to a
pathology not directly related to the ICI therapy. The methods include a method for evaluating a subject comprising measuring the level of one or more biomarkers in a biological sample from the subject, wherein the biomarker(s) are one or more of IL5, CD274, TNFSF4, FAS, IL20, TSLP, TNFSF15, CCL1, IL6, TNF, CLEC4A, NCR1, FGF19, IL5RA, MUC16, CCL3, VCAM1, EPO, IFNL1, MMP3, IL9, IL16, IL36A, FLT1, IL18, IL12RB1, KITLG, LTF, CCL18, LCN2, CXCL13, S100A8, CXCL9, CD79A, CCR7, CXCL1, C3, TREM1, IL7R, CD19, LTB, MS4A1, SAA1, CXCL10, C1QB, TNFRSF17, CTLA4, CXCL6, CD27, CD38, CXCL11, CD163, FCGR3A, ITGAX, CD7, C1QA, RUNX3, SLAMF7, IRF4, SELL, ZAP70, CD48,
SIGLEC1, PDCD1, IL2RB, JAK3, CTSS, CSF2RB, IL2RG, ISG20, EBI3, C2, ITGAL, CCR5, IDO1, LCP1, CD5, CD6, SH2D1A, CYBB, CCL5, IL10RA, VEGFC, IL13RA2, IL36G, MMP9, EGF, CTF1, CHI3L1, IL1R1, TNFRSF8, SPP1, IL15RA, TNFRSF1B, TNFRSF18, TNFRSF1A, CX3CL1, CD40, IL17A, TNFRSF14, CXADR, TNFRSF9, TNFRSF11A, TNFSF11, IL2RA, MDK, IL18BP, LTBR, SLURP1, CSF1, and IL33.