Reduction of the Total IgE Level by Omalizumab in Children and Adolescents

Abstract

Background: Current data from clinical studies show that patients with severe allergic asthma experience a significant improvement from omalizumab. The early and late allergic reactions are inhibited by formation of complexes with free circulating immunoglobulin E (IgE), independent of which antigen activates the allergic cascade. The dosage of omalizumab depends on body weight and IgE level, yet no parameter has been established to guide dosage changes during therapy. The aim of this study was to investigate the value of the determination of total IgE by ADVIA Centaur assay to monitor the therapy progress. Patients and Methods: Nine patients, 8 to 17 years of age, received therapy with omalizumab due to severe allergic bronchial asthma. In addition, the patients had pronounced rhinoconjunctivitis, food allergy, insect sting allergy, and/or neurodermitis. The total IgE in the serum (Sandwich-Immunoassay ADVIA Centaur) was measured in the patients once monthly before each omalizumab injection as a potential progress parameter. Results: Six months after the beginning of therapy with omalizumab, a significant decrease of the total IgE concentration was found, in comparison to the baseline values (p < 0.01). In all patients, the tolerability of omalizumab was very good; there was a reduction in the frequency of the asthma exacerbations and rescue medications. The dosage of inhaled glucocorticoids could be lowered. All patients reported a clearly improved quality of life. Conclusions: The increase of the total IgE concentrations after administration of omalizumab described in the literature could not be confirmed. The value of total serum IgE as a progress parameter should be investigated in controlled studies with regard to sensitivity and specificity of the respective assays. The establishment of a test procedure for therapeutic monitoring appears urgently necessary, so that the appropriate dosage of omalizumab is applied in children and adolescents. Patients receiving omalizumab therapy should be closely monitored.

Keywords:

• allergic bronchial asthma
• IgE assay
• omalizumab
• total immunoglobulin E