Dupilumab improves itch in patients with prurigo nodularis regardless of baseline Ige

Prurigo nodularis (PN) is a chronic inflammatory skin condition characterized by severely itchy cutaneous nodules that have a substantial impact on quality of life. Dupilumab is a fully human monoclonal antibody targeting the interleukin-4 (IL-4) receptor alpha (IL-4Rα), thereby blocking IL-4 and IL-13 signaling, and reducing IgE levels. This analysis assessed whether baseline IgE levels may play a role in PN pathogenesis and predict the extent of clinical response to dupilumab. In two identical, randomized, double-blind, placebo-controlled, 24-week, phase 3 studies, LIBERTY-PN PRIME (NCT04183335) and PRIME2 (NCT04202679), adults with PN inadequately controlled by topical prescription therapies were randomized 1:1 to dupilumab 300 mg every 2 weeks or matched placebo. This post-hoc analysis examines the effect of 24-week dupilumab treatment on itch, as assessed by ≥ 4-point improvement in the Worst Itch Numerical Rating Scale (WI-NRS; scored 0–10), in patients with PN with baseline serum total IgE levels ≤ 150 IU/mL or>150 IU/mL. In total, 311 patients were randomized (dupilumab/placebo n=153/158). 137 patients had IgE ≤ 150 IU/mL at baseline (dupilumab/placebo n=58/79) and 165 patients had IgE>150 IU/mL (dupilumab/placebo n=92/73). At week 24, 56.9% of dupilumab-treated patients with baseline total serum IgE levels ≤ 150 IU/mL and 60.9% with baseline total serum IgE levels>150 IU/mL achieved ≥ 4-point improvement in WI-NRS, compared to 17.7% and 20.6% of placebo-treated patients [nominal P=0.001/P