Omalizumab: well tolerated and effective in refractory chronic idiopathic/spontaneous urticaria
Published Online: July 2013
The Journal of Allergy and Clinical Immunology
Patients with chronic idiopathic urticaria/chronic spontaneous urticaria (CIU/CSU) often have uncontrolled symptoms despite the use of non-sedating H1-antihistamines at up to four times the standard dose. For those patients who remain symptomatic, other treatment options include H2-antihistamines, leukotriene receptor antagonists [LTRAs], dapsone, cyclosporine and methotrexate. However, there is a lack of high-quality clinical evidence to support their use, and immunosuppressants are potentially associated with severe adverse effects. In an original article in The Journal of Allergy and Clinical Immunology (JACI), Kaplan et al. present results from a randomized, double-blind, placebo-controlled study of omalizumab, an anti-immunoglobulin E monoclonal antibody approved as add-on therapy for inadequately-controlled moderate-to-severe allergic asthma and under investigation for use in refractory CIU/CSU.
The primary objective of the study was to assess the safety of omalizumab 300 mg administered at 4-week intervals in patients with CIU/CSU refractory to H1-antihistamines (including up to 4x approved dose) plus H2-antihistamines and/or LTRAs. Efficacy assessments included weekly itch severity score (key secondary endpoint), change from baseline in weekly urticaria activity score, weekly number of hives score, weekly size of largest hive score, health-related quality-of-life (Dermatology Life Quality Index), proportion of angioedema-free days, and proportion of patients who were completely hive- and itch-free.
During 24 weeks of treatment and a subsequent 16-week follow-up period, the incidence and severity of adverse events and serious adverse events were similar between omalizumab and placebo. There were no anaphylactic reactions, malignancies or deaths, and no new safety issues were identified. At Week 12, there was a greater improvement in weekly itch score in the omalizumab group, compared with placebo (-8.6 vs. -4.0; P<.001), with sustained benefit at Week 24 (-8.6 vs. -4.0; P<.001) (see figure). There were also significant improvements with omalizumab, versus placebo, for all other efficacy endpoints.
Overall, this study showed that omalizumab is well tolerated and effective in patients with symptomatic CIU/CSU despite multiple background therapy with H1-antihistamines and H2-antihistamines and/or LTRAs.
(JACI) is the official scientific journal of the AAAAI, and is the most-cited journal in the field of allergy and clinical immunology.