Figure 3
IL-19 is highly correlated with PASI in psoriasis patients treated with the JAK1/2 inhibitor baricitinib. (a) We obtained samples from 270 patients enrolled in a phase 2 psoriasis study (NCT01490632) for the JAK1/2 inhibitor baricitinib19. Patients were administered placebo or 2, 4, 8, or 10 mg of baricitinib QD for 12 weeks. Samples were collected at baseline and after 12 weeks of treatment. Circulating IL-19 was measured at baseline and after 12 weeks of treatment with baricitinib (2, 4, 8, or 10 mg QD) or placebo in patients with psoriasis. All data from baseline and after 12 weeks of treatment are shown. Collectively, serum IL-19 levels were highly correlated with PASI (Spearman’s r = 0.72, p < 0.0001). (b) Serum IL-19 was measured in psoriasis patients at baseline and after 12 weeks of treatment with placebo (PBO) or baricitinib (BARI) (2, 4, 8, or 10 mg QD). Data plotted are least square means ± standard error of the mean estimated from a mixed effects model using an unstructured covariance matrix. Model fitting was performed using log10 transformed IL-19 concentrations. The dashed horizontal line indicates the upper limit of normal (21 pg/mL). Week 12 comparisons of baricitinib to placebo: 2 mg (p = 0.31), 4 mg (p = 0.063), 8 mg (p = 0.022), and 10 mg (p < 0.0001). (c) Serum IL-19 levels in psoriasis patients after 12 weeks of treatment with placebo or baricitinib (2, 4, 8, or 10 mg QD) are plotted versus PASI at 12 weeks. The dashed horizontal line indicates the upper limit of normal. PASI >75 improvements at 12 weeks were correlated with reduction of circulating IL-19 concentrations. One-way ANOVA (p < 0.0001).
