Background: Omalizumab is a humanized monoclonal anti-IgE for the treatment of severe allergic asthma. Because omalizumab targets an immune system molecule, there has been particular interest in the drug's safety.
Methods: To establish the efficacy and safety of subcutaneous omalizumab as add-on therapy to corticosteroids, a systematic review of placebo-controlled studies was performed. Primary outcomes were reduction of steroid use and asthma exacerbations. Secondary outcome measures included lung function, rescue medication use, asthma symptoms, health-related quality of life, and adverse effects.
Results: Eight trials (3,429 participants) fulfilled the selection criteria. At the end of the steroid-reduction phase, patients taking omalizumab were more likely to be able to withdraw from corticosteroids completely compared with those taking placebo (relative risk [RR] = 1.80; 95% CI, 1.42-2.28; P = .00001). Omalizumab patients showed a decreased risk of asthma exacerbations at the end of the stable (RR = 0.57; 95% CI, 0.48-0.66; P = .0001) and adjustable-steroid phases (RR = 0.55; 95% CI, 0.47-0.64; P = .0001); post-hoc analysis suggests this effect was independent of duration of treatment, age, severity of asthma, and risk of bias. The frequency of serious adverse effects was similar in the omalizumab (3.8%) and placebo (5.3%) groups. However, injection site reactions were more frequent in the omalizumab patients (19.9% vs 13.2%). There were no indications of increased risk of hypersensitivity reactions, cardiovascular effects, or malignant neoplasms.
Conclusions: Data indicate that the efficacy of add-on omalizumab in patients with moderate-to-severe allergic asthma is accompanied by an acceptable safety profile.