Prevalence of omalizumab-resistant chronic urticaria and real-world effectiveness of dupilumab in patients with omalizumab-refractory chronic urticaria: a single-centre experience

Chronic urticaria (CU) is characterized by weals (hives) angio-oedema (or both) that last for >= 6 weeks, with chronic spontaneous urticaria (CSU) being the most common subtype. Patients with omalizumab-refractory CSU represent an unmet clinical need. In this study, we aimed to assess the prevalence and predictors of omalizumab failure in a large cohort of patients with CU and assess the effectiveness of dupilumab for omalizumab-refractory CU. Of 338 patients with CU, 33 received omalizumab; 69.7% (n = 23) were responders and 30.3% (n = 10) were nonresponders. Bivariate regression demonstrated that female sex [adjusted odds ratio (aOR) 1.53, 95% confidence interval (CI) 1.14-2.06], higher baseline weekly urticaria activity score (aOR 1.05, 95% CI 1.01-1.09) and older age (controlling for sex) (aOR 1.00, 95% CI 1.00-1.01) were associated with omalizumab failure. Of 10 patients with omalizumab-refractory CU, 3 were well controlled with ciclosporin (all children), whereas the 7 adults failed a mean [standard deviation (SD)] of 5.6 (2.6) treatments, including ciclosporin. All seven achieved a complete response with dupilumab, with time to response varying between 1 and 6 months. While our results suggest a favourable efficacy of dupilumab in patients with omalizumab-refractory CU, future confirmatory studies are required. Patients with omalizumab-resistant chronic spontaneous urticaria represent an unmet clinical need. In this cohort of 338 patients with chronic urticaria, 3.0% (10 patients) failed treatment with omalizumab and antihistamines. Omalizumab failure was associated with female sex, higher baseline weekly urticaria activity score and older age. Three patients (all children) were well controlled and tolerated ciclosporin, whereas the seven adults failed a mean (standard deviation) of 5.6 (2.6) treatments, including ciclosporin, while achieving a complete response with dupilumab, with time to response varying between 1 and 6 months.