Real-World Long-Term Management of Chronic Urticaria Patients with Omalizumab: Safety, Effectiveness, and Predictive Factors for Successful Outcome

Background/Objectives: Omalizumab is a monoclonal anti-IgE antibody approved for the treatment of chronic urticaria. There are no established or validated prognostic markers currently available to identify likely responders. The aim of this study was to retrospectively analyze a cohort of chronic urticaria patients treated with omalizumab, in order to determine the clinical and laboratory characteristics associated with complete response to therapy. Methods: Medical records of chronic urticaria patients receiving omalizumab were reviewed. The following parameters were collected: age, sex, disease duration, Urticaria Activity Score over 7 days (UAS7), time to response, total serum IgE levels, presence or absence of atopy, neutrophil-to-lymphocyte ratio, eosinophil and basophil counts, presence or absence of autoimmune conditions, and treatment duration. Complete response was classified as dependent on continued drug administration or drug-free (sustained remission after discontinuation). Adverse events were also recorded. Results: Omalizumab was well tolerated by all patients, with no serious adverse events reported. Complete response was achieved in 81.3% of patients; partial and no responses were observed in 8.3% and 10.1%, respectively. The majority of responders (~79.5%) maintained complete control of hives with low-dose omalizumab; subsequently, most of these patients eventually achieved sustained, drug-free remission. Total serum IgE levels appeared to predict complete response, with 164.7 IU/mL identified as the cut-off value potentially distinguishing responders from nonresponders. Conclusions: Omalizumab is a safe and effective treatment for chronic urticaria. Total serum IgE levels may help identify complete responders. Long-term low-dose regimens could be considered to reduce the economic burden on healthcare systems, although this is currently an off-label approach.