No abstract

IgE plays a key role in allergic asthma. We investigated whether omalizumab treatment of patients with moderate to severe allergic asthma leads to changes in inflammatory mediators and clinical symptoms. This sub-study was conducted on 35 patients with a positive skin prick test (SPT) requiring daily administration of beclomethasone dipropionate (500–1,000 µg), who participated in a multicentre, randomised, double-blind, placebo-controlled study. Omalizumab or placebo was administered at 0.016 mg/kg/IgE every 4 weeks. Patients recorded peak expiratory flow, asthma symptom score and β₂-agonist use in daily diaries and spirometry was performed at each visit. β₂-Agonist use and SPT wheal reaction decreased significantly (p < 0.05). Circulating levels of IL-5, IL-6, IL-8, IL-10, IL-13 and s-ICAM were measured before and after 16 weeks of treatment. IL-13 and s-ICAM were measured before and after 16 weeks of treatment. IL-13 decreased significantly (p < 0.01). IL-5 and IL-8 decreased in the omalizumab group compared to baseline. The other circulating mediators did not demonstrate any changes. Histamine release was significantly reduced (p < 0.01). Airway resistance (p < 0.05) and the provocative concentration inducing a 20% decrease in FEV₁ (p < 0.05) were measured before, after 16 weeks, and 3 months after completion of treatment. Both parameters decreased significantly (p < 0.05). Peripheral eosinophil count decreased significantly compared to placebo (p < 0.01). These findings suggest that omalizumab has potential as a novel treatment for allergic asthma.

The aim of the present study was to determine the effect of treatment with omalizumab, an anti-immunoglobulin E antibody, on asthma-related quality of life (AQoL) in patients with moderate-to-severe allergic asthma.A total of 546 patients with allergic asthma were randomised to double-blind subcutaneous treatment with either placebo or omalizumab for 52 weeks. A constant beclomethasone dipropionate dose was maintained during the first 16 weeks (steroidstable phase). This was followed by a 12-week steroid-reduction phase. The core study was followed by a 24-week double-blind extension phase. AQoL was evaluated at baseline and at the end of the steroid-stable (week 16), steroid-reduction (week 28) and extension phases (week 52) using the Juniper Asthma Quality of Life Questionnaire (AQLQ).Baseline AQLQ scores were comparable for the two treatment groups. Relative to placebo, omalizumab-treated patients demonstrated statistically significant improvements from baseline across all four AQLQ domains, as well as overall AQoL score, at weeks 16 (except environmental exposure), 28 and 52. Patients on omalizumab were also more likely to achieve clinically significant improvements in AQoL during the course of the study. Overall, almost 70% of patients and investigators rated treatment with omalizumab as "excellent/good", compared with y40% of placebo recipients.Clinical studies show that omalizumab enhances disease control whilst reducing corticosteroid consumption in patients with allergic asthma. The results of the present study show that these changes are paralleled by improvements in asthma-related quality of life that are meaningful to such patients.

Eosinophils store, produce and release NGF, BDNF and NT-3. They are a possible source of elevated neurotrophin levels found in allergy and asthma.