Omalizumab boosts time to clinically meaningful response in chronic spontaneous urticaria
Click Here to Manage Email Alerts
LOUISVILLE, Ky. — Patients assigned omalizumab for moderate to severe chronic spontaneous urticaria experienced superior time to clinically meaningful response compared with those on placebo, according to study results.
“Improvements in urticaria symptoms were observed as early as 1 week in some patients after omalizumab initiation,” Thomas B. Casale, MD, chief of clinical and translational research in the division of allergy and immunology at University of South Florida Morsani College of Medicine, said at the American College of Allergy, Asthma & Immunology Annual Scientific Meeting.
The researchers conducted post-hoc analyses of pooled data from the ASTERIA I (n = 319) and ASTERIA II (n = 323) phase 3 pivotal global clinical trials. Aged 12 to 75 years, these patients had symptomatic moderate to severe chronic spontaneous urticaria (CSU) even with standard-dose H1 antihistamine treatment.
Patients received 150 mg or 300 mg injections of omalizumab (Xolair; Genentech, Novartis) or placebo every 4 weeks for 12 weeks. Assessments included the 7-Day Urticaria Activity Score (UAS7), which ranged from 0 (no symptoms) to 42.
“The minimally important difference response was defined as a reduction from baseline in UAS7 of greater than or equal to 11 points,” Casale said. “Responders were defined as UAS7 less than or equal to 6, with complete responders [defined as] UAS7 equal to 0.”
The median time to minimally important difference was 5 weeks for the placebo and 2 weeks for both doses of omalizumab, meeting statistical significance (P < .0001 for both).
“The percent of patients with a response to omalizumab UAS7 less than or equal to 6 increased dose-dependently over time,” Casale said.
At week 1, 6% of the patients on 150 mg of omalizumab, 6% of those on 300 mg and 2% of those on placebo had responded to treatment. At week 6, responders increased to 49% of the 300 mg cohort, 33% of the 150 mg cohort and 14% of those on placebo.
By week 12, 59% of the participants on 300 mg of omalizumab, 41% of those on 150 mg of omalizumab and 15% of those on placebo were responders.
“The percent of patients with a complete response to omalizumab, UAS0, increased dose-dependently over time as well,” Casale continued.
At week 1, only 1% of the 150 mg cohort and no one in the other cohorts achieved complete response. By week 6, percentages increased to 32% of those on 300 mg, 14% of those on 150 mg and 4% of those on placebo. Week 12 finished with complete response achieved by 40% of the 300 mg group, 19% of the 150 mg group and 7% of the placebo group.
“In conclusion, patients with moderate to severe CSU receiving omalizumab had a significantly superior time to clinically meaningful response compared with placebo,” Casale said. “Our findings confirm, however, that response to omalizumab varies between patients but that some patients may benefit from a longer duration of treatment.”