Predictive cytokines of omalizumab in the treatment of chronic spontaneous urticaria.

BACKGROUND

Omalizumab, an anti-IgE biological agent, is commonly prescribed as a second-line therapy for Chronic Spontaneous Urticaria (CSU). However, there is a lack of biomarkers to predict which CSU patients will respond favorably to omalizumab.

OBJECTIVE

Our study aims to identify cytokine markers associated with the efficacy of omalizumab in treating CSU.

METHODS

We conducted a prospective study, enrolling antihistamine-resistant CSU patients from Tongji Hospital between Feburary and August 2023. All patients received a 16-week course of omalizumab (300 mg, administered every 4 weeks). Following 16 weeks of omalizumab treatment, patients were categorized into responder group and non-responder groups based on their UAS7 scores at the 16th week, using a cut-off value of 7. Serum total IgE (TIgE) and cytokine levels were measured at baseline and at the 16th week.

RESULTS

A total of 59 patients were enrolled in the study, 46 (78.0 %) responded positively to omalizumab. The responder group had lower UAS7 and DLQI scores at 4 and 16 weeks compared to their baseline and the non-responder group. There was no statistical difference in baseline TIgE levels between the two groups, but TIgE significantly increased in both groups after 16 weeks of omalizumab treatment. The responder group had higher baseline levels of IL-2, IL-13, IL-31, and IL-33 than the non-responder group. After 16 weeks of omalizumab treatment, the levels of IL-5, IL-31, and IL-33 were higher in the responder group than in the non-responder group. The AUC of baseline IL-2, IL-13, IL-31, and IL-33 in predicting responses to omalizumab were 0.8250, 0.8125, 0.7938, and 0.7813 (all P < 0.05), and the cut-off value were 154.5 pg/ml, 41.5 pg/ml, 100.8 pg/ml and 3330 pg/ml respectively.

CONCLUSION

CSU patients with high levels of IL-2, IL-13, IL-31, and IL-33 may potentially benefit from omalizumab treatment.