TNF and rheumatoid arthritis: Several studies have reported that SNPs of STAT4 are associated with the clinical efficacy of tumor necrosis factor (TNF) inhibitors in the treatment of RA patients (145), and the STAT4 rs7574865 T allele is associated with the absence of a good/moderate EULAR response at 2 years of treatment in RA patients and ETN-treated patients (146).