Introduction: This study examined the remission probability and duration in chronic spontaneous urticaria (CSU) patients resistant to second-generation H1-antihistamines (sgAHs) undergoing omalizumab treatment.
Methods: This is a retrospective observational study of 176 adult CSU patients exhibiting a significant pruritus component (≥ 8) of the weekly urticaria activity score (UAS7) despite four daily sgAH tablets and starting omalizumab treatment with 300 mg every 4 weeks. After excluding 13 nonresponders, we analyzed 163 omalizumab responders (mean age 51.8 years, 74.4% female). The intervals between applications were increased. Discontinuation was considered for patients that remained asymptomatic on a gradually reduced dosage (to 150 mg every 12 weeks) without sgAHs.
Results: Omalizumab discontinuation was possible in 25.8% (42/163). The duration of omalizumab treatment before remission ranged from 7 to 63 months. Twenty-one patients (50.0%) maintained complete remission until the end of the observation period (September 2021) for 8 to 68 months. Of the relapsed patients, 71.4% (15/21) effectively controlled CSU with sgAHs. Six patients (28.6%; 6/21) required omalizumab reintroduction after 6 to 40 months of remission, responding favorably.
Conclusions: The study shows that a quarter of severe CSU patients achieve long-term remission. In addition, sgAHs effectively manage symptoms in a majority of relapsed cases, and those requiring omalizumab reintroduction respond favorably.