Clinical Factors Associated With High-Dose Omalizumab Use in Chronic Spontaneous Urticaria: A Retrospective Real-World Study

Abstract

BackgroundChronic spontaneous urticaria (CSU) is a mast cell-driven skin disorder characterized by wheals, angioedema, or both lasting more than 6 weeks. While standard-dose omalizumab (300 mg every four weeks) is effective in many cases, a subset of patients requires higher doses. Predictive biomarkers for such treatment escalation remain unclear.ObjectiveTo identify clinical and laboratory parameters associated with the need for high-dose omalizumab therapy (450-600 mg/4 weeks) in patients with CSU.MethodsThis retrospective observational study included 199 CSU patients treated with omalizumab following the failure of fourfold second-generation H1 antihistamines. Patients were grouped by dose regimen: standard dose (n = 168) and high dose (n = 31). Demographic, clinical, and laboratory data were analyzed and compared between groups using appropriate statistical tests.ResultsIn unadjusted analyses, patients in the high-dose omalizumab group were significantly older (mean age 45.94 vs. 41.29 years, p = 0.050), had higher BMI (28.30 vs. 25.88, p = 0.016), showed a higher prevalence of prior cyclosporine use (9.7% vs. 1.2%, p = 0.028), exhibited elevated D-dimer levels (32.3% vs. 15.6%, p = 0.027), and presented with angioedema (45.2% vs. 21.6%, p = 0.005) compared with the standard-dose group. However, in multivariate logistic regression analysis, only elevated D-dimer levels remained an independent predictor of high-dose omalizumab use.ConclusionOlder age, higher BMI, angioedema, and prior cyclosporine use were more frequent among patients receiving high-dose omalizumab in unadjusted analyses; however, only elevated D-dimer levels remained independently associated with dose escalation. This readily available biomarker may help identify CSU patients who are more likely to require high-dose omalizumab, although prospective multicenter studies are needed to confirm these findings.