FDA Says ‘Yes’ to Xolair (Omalizumab) for Patients With Chronic Hives
First approved treatment since H1-antihistamines
The FDA has approved Xolair (omalizumab, Genentech/Novartis) for the treatment of chronic idiopathic urticaria (CIU), a form of chronic hives. The new use is for patients 12 years of age and older who remain symptomatic despite treatment with H1-antihistamine therapy. Xolair is not used to treat other forms of urticaria (hives) and is not for use in children less than 12 years of age.
Xolair is the first medicine approved by the FDA for the treatment of CIU since H1-antihistamines.
CIU is characterized by hives that spontaneously occur without an identifiable cause and re-occur for 6 weeks or more. The symptoms of CIU include red, swollen, itchy, and sometimes painful hives on the skin that can be burdensome and that can last for many months and even years. Nearly 50% of these patients remain symptomatic despite treatment with approved doses of H1-antihistamines — the only previously FDA-approved therapy for CIU. In the U.S., it is estimated that approximately 1.5 million people have CIU. Women are twice as likely as men to experience CIU, and most people develop symptoms between the ages of 20 and 40 years.
The clinical profile of omalizumab for the treatment of CIU was evaluated in two pivotal trials, ASTERIA I and ASTERIA II. In these studies, 641 patients 12 to 75 years old received subcutaneous injections of omalizumab (75 mg, 150 mg, or 300 mg) or placebo. Omalizumab or placebo was given every 4 weeks for 24 weeks (ASTERIA I) or 12 weeks (ASTERIA II). In addition, the patients in both trials continued to receive the H1-antihistamine treatment they had been taking for CIU before starting treatment with omalizumab.
Both studies used the Itch Severity Score (ISS) and the weekly hive count score, where potential scores ranged from 0 to 21 for both scales, to determine the efficacy of omalizumab.
In the ASTERIA I trial, omalizumab 150 mg improved the ISS from the starting measurement by a reduction of 6.7 (47%) at week 12, and omalizumab 300 mg improved the ISS from the starting measurement by a reduction of 9.4 (66%), compared with a reduction of 3.6 (25%) for the patients given placebo. Moreover, a larger proportion of patients (36%) treated with omalizumab 300 mg reported no itching and no hives at week 12 compared with patients treated with omalizumab 150 mg (15%) and placebo-treated patients (9%). Similar results were observed in the ASTERIA II study. The 75-mg dose of omalizumab did not demonstrate consistent evidence of efficacy and is not approved for use.
The most common side effects in patients treated with omalizumab were nausea; headaches; swelling of the inside of the nose, throat, or sinuses; cough; joint pain; and upper respiratory tract infection. Xolair (omalizumab) was originally approved in the U.S. in 2003 for people 12 years of age and older with moderate-to-severe persistent allergic asthma caused by year-round allergens in the air and not controlled by inhaled steroids. Xolair should not be used to treat other allergic conditions. It is not a rescue medication and should not be used to treat sudden asthma attacks. Xolair should not be used in children under 12 years of age.
Omalizumab is a recombinant DNA-derived humanized immunoglobulin G1-kappa (IgG1-kappa) monoclonal antibody that selectively binds to human IgE. The antibody is produced by a Chinese hamster ovary cell suspension culture in a nutrient medium containing the antibiotic gentamicin. Gentamicin is not detectable in the final product.