Omalizumab for Chronic Urticaria

Abstract

.These studies suggest that omalizumab will be a good therapeutic option for patients with CIU who do not respond to either licensed or higher doses of H1 antihistamines. Chronic idiopathic urticaria (CIU)echronic spontaneous urticaria (CSU) is defined as hives and/or angioedema that occurs daily, or almost daily, for >6 weeks independent of external stimuli. CIU has significant detrimental effects on quality of life. H1 antihistamines are the only approved treatment in CIU, but more than 50% of patients are unresponsive to licensed doses of H1 antihistamines. Add-on treatments (all unapproved by the US Food and Drug Administration) include leukotriene receptor antagonists, systemic steroids, cyclosporine, and methotrexates, but the data to support their use are not of high quality. Therefore, there is a need for new, efficacious, and well-tolerated treatments for patients with H1 antihistamine refractory CIU. Maurer et al recently reported results from 1 of the 3 phase III anti-IgE mAb omalizumab studies (Asteria-II) for treatment of CIU. They evaluated the efficacy and safety of omalizumab compared with placebo in 323 patients, 12 to 75 years of age, with moderate-to-severe refractory CIU despite receiving concomitant licensed doses of H1 antihistamine therapy. This was a global, multicenter, 1:1:1:1 randomized, doubleblind, placebo-controlled trial that compared 3 subcutaneous injections, separated by 4 weeks, of omalizumab at doses of 75 mg, 150 mg, or 300 mg, or placebo, followed by a 16-week observation period. The primary end point was the change from baseline in weekly itch severity score (ISS) at week 12. Major secondary end points included a change from baseline in a weekly number of hives score, the proportion of patients with a weekly urticaria activity score (UAS7, a composite score of the weekly ISS and weekly number of hives score [scale 0e42]) 6, change from baseline in overall Dermatology Life Quality Index (DLQI), and the proportion of angioedema-free days from week 4 to week 12. Key inclusion criteria were a CIU diagnosis for 6 months, the presence of itch and hives for 8 consecutive weeks at any time before enrollment despite the current use of H1 antihistamine treatment, weekly UAS7 score 16, and itch component of UAS7 8 (scale 0-21) during 7 days before randomization (week 0). Key exclusion criteria were clearly defined underlying etiology for chronic urticaria (cold, physical,