In patients with ulcerative colitis (n = 40), baseline IL-8 values > 8.6 pg/mL and a decrease of IL-6 values > 0.4 pg/mL from T0 to T1 were significant and independent predictors of clinical response after 12 months of vedolizumab therapy (odds ratio (OR) = 6.96, 95% CI 1.27–38.22, p = 0.026 and OR = 7.29, 95% CI 1.42–37.50, p = 0.017, respectively). This evidence concerns the gene CXCL8 and ulcerative colitis.