By week 2, 39% of patients receiving omalizumab achieved a weekly UAS of 6 or less, HCPLive reported, compared with 6% receiving placebo in pooled ASTERIA I/II data.
At week 1, 6% of patients receiving omalizumab achieved this response level, while 2% of the placebo group reached the same threshold. No patients in either group achieved a complete response, defined as a weekly UAS of 0, during the first week.
By week 2, complete response rates reached 13% for the omalizumab arm and 3% for the placebo arm. Mean UAS7 scores at baseline stood at 30.4 for omalizumab and ranged from 30.2 to 30.6 in the remibrutinib arms of the REMIX-1 and REMIX-2 trials.
Indirect comparisons with remibrutinib data
Investigators used published data from pooled phase 3 trials of remibrutinib versus placebo to run unmatched cross-trial comparisons. They evaluated placebo-adjusted differences in mean daily UAS using 2-sample t tests.
Placebo-adjusted improvements in mean daily UAS did not differ significantly between omalizumab and remibrutinib at day 2, day 7, or day 14. P values for these time points were .52, .39, and .15 respectively.
Baseline Dermatology Life Quality Index scores ranged from 12.9 to 14.2 across all evaluated trial arms. The proportion of female patients reached 76.9% in the omalizumab arm, compared with 67.7% and 65.7% in the two remibrutinib arms.
Trial limitations and funding disclosures
The analysis was post hoc and used unmatched cross-trial comparisons without adjustment for underlying population differences. The comparative trials were conducted roughly a decade apart from one another.
Genentech, which markets omalizumab, funded the study presented at the American College of Allergy, Asthma & Immunology 2026 Annual Scientific Meeting in Phoenix, Arizona. Three of the six study authors are Genentech employees.
“By post hoc indirect comparison, improvements in disease activity appeared to be similar for omalizumab vs remibrutinib during the first 14 days post treatment initiation, highlighting that omalizumab remains an effective treatment option for patients with CSU,” Joshi and colleagues wrote.
Frequently asked questions about CSU treatments
What is a weekly UAS score of 6 or less?
A weekly urticaria activity score (UAS7) of 6 or less indicates low disease activity in chronic spontaneous urticaria patients. Baseline mean scores across the pooled trial arms exceeded 30.
How were omalizumab and remibrutinib compared?
Investigators conducted unmatched indirect comparisons using published data from the pooled phase 3 REMIX-1 and REMIX-2 trials involving 613 active-treatment patients and 312 placebo patients. No head-to-head clinical trial has been conducted between the two agents.
What were the female patient percentages in the trials?
Female patients accounted for 76.9% of the omalizumab arm in the pooled ASTERIA data. The remibrutinib trial arms included 67.7% and 65.7% female patients.
Safety results for both trial programs had been published previously and were not reanalyzed in this evaluation.