Omalizumab, Anti-IgE Recombinant Humanized Monoclonal Antibody, for the Treatment of Severe Allergic Asthma

Background: A recombinant humanized anti-IgE mAb, omalizumab, forms complexes with free IgE, blocking its interaction with mast cells and basophils; as a consequence, it might be effective in the treatment of asthma.

Objective: The purpose of this study was to evaluate the efficacy and safety of omalizumab in the treatment of inhaled corticosteroid-dependent asthma.

Methods: In this phase III, double-blinded, placebo-controlled trial, 525 subjects with severe allergic asthma requiring daily inhaled corticosteroids were randomized to receive placebo or omalizumab subcutaneously every 2 or 4 weeks, depending on baseline IgE level and body weight. Inhaled corticosteroid doses were kept stable over the initial 16 weeks of treatment and tapered during a further 12-week treatment period.

Results: Omalizumab treatment resulted in significantly fewer asthma exacerbations per subject and in lower percentages of subjects experiencing an exacerbation than placebo treatment during the stable steroid phase (0.28 vs 0.54 [P =.006] and 14.6% vs 23.3% [P =.009], respectively) and during the steroid reduction phase (0.39 vs 0.66 [P =.003] and 21.3% vs 32.3% [P =.004], respectively). Beclomethasone dipropionate reduction was significantly greater with omalizumab treatment than with placebo (median 75% vs 50% [P <.001]), and beclomethasone dipropionate discontinuation was more likely with omalizumab (39.6% vs 19.1% [P <.001]). Improvements in asthma symptoms and pulmonary function occurred along with a reduction in rescue beta-agonist use. Omalizumab was well tolerated, with an adverse-events profile similar to that of placebo.

Conclusion: The addition of omalizumab to standard asthma therapy reduces asthma exacerbations and decreases inhaled corticosteroid and rescue medication use.