Tools in addition to the guideline-recommended 7-day Urticaria Activity Score (UAS7) to monitor chronic idiopathic/spontaneous urticaria (CIU/CSU) disease activity could be useful to clinicians. We therefore compared the 4-item Urticaria Control Test (UCT), which assesses symptoms, quality of life, treatment effectiveness, and urticaria control in the past 4 weeks, to UAS7 and Dermatology Life Quality Index (DLQI).
In the Phase IV, XTEND-CIU study, UCT, UAS7, and DLQI were administered during the open-label (baseline to week 24) and double-blind periods (week 24 to week 48). We calculated Pearson correlations of UCT scores with UAS7 and DLQI scores for changes from baseline to week 24. UCT score changes from week 24 to week 48 were analyzed using 2-sample t-tests after applying last-observation-carried-forward methodology for missing data between visits.
UCT, UAS7 and DLQI scores improved through the 24-week open-label treatment period with omalizumab. Change in UCT from baseline to week 24 strongly correlated with UAS7 and DLQI: r =-0.768 and r=-0.602, respectively. Similar to UAS7 and DLQI improvements, UCT improvements from weeks 24 to 48 significantly favored omalizumab (n=80) vs placebo (n=53): differences in mean (SD) changes were –1.7 (4.44) and 7.8 (6.66), respectively, p<0.0001.
Strong correlations of the UCT with UAS7 and DLQI during the open-label period of the XTEND-CIU study on treatment with omalizumab and statistically significant efficacy results during the double-blind period suggest that the UCT could be used in clinical practice, in addition to or even potentially in lieu of UAS7.