Mild Bilateral Wheezing: Is Omalizumab Efficacious?
How efficacious is omalizumab (Xolair), and is it possible to use it as initial therapy if a patient is still on prednisone and having mild bilateral wheezing?

Richard Newman, MD; R. Farid, MD

Omalizumab may be used if the patient is still on prednisone and having mild bilateral wheezing. However, it is not recommended that omalizumab be used as initial therapy or as therapy for acute attacks. Omalizumab is indicated for patients with moderate-to-severe persistent asthma who are 12 years of age and older, who have an immunoglobulin (Ig)E level between 30 and 700, who have at least 1 positive skin test to a perennial allergen, and who are not controlled on the currently available therapy.

Several, very important clinical trials have been published regarding the efficacy of omalizumab. First, a randomized, phase 3, 28-week, double-blind trial in children 6-12 years of age showed that omalizumab reduced exacerbations in a statistically significant manner and led to reduced doses of inhaled steroid that were needed for control. The 2 pivotal trials comparing omalizumab with placebo in patients just on beclomethasone showed that there was a significant reduction in exacerbations during both the steroid-stable phase and the steroid-reduction phase. There was a 67% greater ability to reduce inhaled corticosteroid dose on active treatment, 46% decrease in "as needed" bronchodilator use, 50% decrease in nocturnal symptoms, and 71% improvement in quality of life compared with placebo.

A more recent trial compared omalizumab with placebo in patients on the Global Initiative for Asthma (GINA) 2002 step 4 treatment, which includes a long-acting beta-agonist, an inhaled corticosteroid, and leukotriene modifiers. In this study, there was a 26% decrease in exacerbations when omalizumab was added compared with the placebo group. The patients who are most likely to respond to omalizumab require beclomethasone-equivalent doses of greater than 800 mcg/ day, forced expiratory volume in 1 second (FEV1) less than 65% predicted, or a history of emergency department or hospitalizations in the last year.

When the pooled studies of all the clinical trials were analyzed, approximately two thirds of the patients treated with omalizumab showed good response.