Does omalizumab modify a course of recalcitrant chronic spontaneous urticaria?: A retrospective study in Asian patients.

Omalizumab has been approved for the treatment of recalcitrant chronic spontaneous urticaria (CSU). However, it remains unanswered whether omalizumab modifies a CSU course. We aimed to study a course of CSU after omalizumab treatment in an Asian population. Medical records of recalcitrant CSU patients who attended Siriraj Hospital between 2013 and 2017 were reviewed. All patients receiving omalizumab treatment were followed after the first injection for at least 1 year. Of 15 patients receiving omalizumab treatment, 11 patients (73.3%) responded well to 150 mg while the rest required 300 mg. The median follow-up period was 18 months (range, 13.5-25.3). Three patterns of response were proposed and measured: excellent (disease remission over than 6 months) was found in 20%; good (injection interval extended longer than 6 months) was found in 27%; and modest (frequently required injections) was found in 53%. The mean duration of complete remission was 33 weeks (range, 26-38). Two-thirds of patients had disease relapse and required omalizumab injections to control symptoms. The other third did not show relapses for at least 69 weeks of the follow-up period. After 1 year of treatment, Kaplan-Meier curves estimated that a higher percentage (86.7%) of recalcitrant CSU patients receiving omalizumab treatment would be free of symptoms (weekly Urticaria Activity Score = 0) without prednisolone and/or cyclosporin as compared with 42% of patients not receiving omalizumab treatment. In conclusion, patients seem to be easily and safely manageable with omalizumab. Prednisolone and cyclosporin could be discontinued in all patients. Further studies are needed to conclude whether omalizumab can exactly modify CSU.