A 10-Year Real-World Analysis of Omalizumab Use in Chronic Spontaneous Urticaria Patients at a Dermatology Clinic.

Objectives: Chronic spontaneous urticaria (CSU) is characterized by recurrent wheals and/or angioedema lasting more than 6 weeks. The disease is marked by unpredictable, severe itching attacks, significantly impacting patients' quality of life and often prompting them to seek medical treatment. This study aimed to evaluate the efficacy of omalizumab in patients with CSU and identify the factors that determine its effectiveness.

Methods: This retrospective descriptive study analyzed registered data of 159 patients with CSU who received omalizumab at a tertiary dermatology clinic. The study recorded patient demographics, allergic conditions, omalizumab dosage, treatment response time, efficacy, duration of use, and additional medications. It also included assessments of total IgE levels.

Results: Of 159 patients with CSU, 112 (70.4%) were females, and 42 (29.6%) were males with a median age of 43 years (IQR = 20). Among the patients, 156 (98.1%) received a 300 mg dose of omalizumab, while 3 (1.9%) received 450 mg. Additionally, 41 (25.8%) required antihistamines and corticosteroids in addition to omalizumab, while 118 (74.2%) were treated with omalizumab alone. The median response time was 3 months, with 116 (73%) showing complete responses and 39 (24.5%) showing partial responses. Four patients (2.5%) showed no response. When patients were categorized into two groups-those receiving only omalizumab and those on combination therapy, the median response time to omalizumab was statistically significantly longer in the combination therapy group (mean=2.53±0.76, median=3, IQR=1 vs. mean=3.49±1.63, median=3, IQR=0). When patients were categorized into two groups based on a total IgE cut-off value of 20 IU/ml, the group with IgE levels greater than 20 had a significantly higher proportion of full responders.

Conclusion: The majority of patients with CSU in this study responded well to omalizumab, with a significant proportion achieving complete responses. Additionally, higher IgE levels (>20 IU/ml) were associated with a greater likelihood of full response to treatment. These findings suggest that omalizumab is an effective agent for CSU, with the possibility of enhanced response in patients with elevated IgE levels.