For the KEGG pathway, nonresponders were positively correlated with sulfur metabolism, complement and coagulation cascades, cytosolic and sensing pathways, adipocytokine signaling pathways, Toll-like receptor signaling pathways, receptor tyrosine kinase (ERBB) signaling pathways and so on (Figure 3B, Supplementary Table 3), which might be related to nonresponse to IFX therapy for RA. This evidence concerns the gene NTRK1 and rheumatoid arthritis.