BACKGROUND Severe Pediatric Allergic Asthma (SPAA) induces a huge economic burden in terms of direct, indirect and intangible costs. The use of omalizumab for the treatment of these patients has produced a significant improvement in several clinical outcomes, but at the same time, the cost for the management of the disease has also increased. The aim of this report was to evaluate whether the use of omalizumab is cost-effective. METHODS A sample of 426 children with SPAA from the ANCHORS study was used to calculate the Incremental Cost Effectiveness Ratio (ICER) for the avoidance of Moderate to Severe Exacerbations (MSE), and also for the improvement in childhood Asthma Control Test (c-ACT) or the Asthma Control Questionnaire (ACQ5). We retrospectively collected data of health encounters and drug consumption before and up to six years after the beginning of the treatment with omalizumab. RESULTS The ICER per avoided MSE was \euro2,107 after one year, and it consistently decreased to \euro656 in those followed up to six years. Similarly, the ICER for the Minimally Important Difference in control tests showed a decrease from \euro2,059 to \euro380 per each 0.5 points of improvement in ACQ5, and from \euro3,141 to \euro2,322 per each 3 points improvement in c-ACT, at years 1 and 6 respectively. CONCLUSION The use of OMZ is a cost-effective option for most children with uncontrolled SPAA, mainly those who have frequent exacerbations, showing progressively reduced costs in successive years of treatment.

Background: Various studies have assessed omalizumab outcomes in the clinical practice setting but follow-up and/or number of patients included were limited. We aim to describe the long-term outcomes of pediatric patients with severe persistent allergic asthma receiving omalizumab in the largest real-life cohort reported to date. Methods: ANCHORS was a multicenter, observational, retrospective cohort study conducted in 25 Pediatric Allergy and Pulmonology units in Spain. We collected data of patients <18 years and initiating omalizumab between 2006-2018, from the year prior to omalizumab initiation to discontinuation or last available follow-up. The primary outcome was the evolution of the annual number of moderate-to-severe exacerbations compared to the baseline period. Results: Of the 484 patients included, 101 (20.9%) reached six years of treatment. The mean±standard deviation number of exacerbations decreased during the first year of treatment (7.9±6.6 to 1.1±2.0, p<0.001) and remained likewise for up to six years. The other clinical parameters assessed also improved significantly during the first year and stabilized or continued to improve thereafter. The percentage of patients experiencing adverse events was consistently low, and the main reason for discontinuation was good disease evolution. Conclusion: In this large, long-term, observational study, moderate-to-severe exacerbations decreased significantly from the first year of treatment with omalizumab. The beneficial effect was maintained in the long-term, along with a good safety profile. Our results position omalizumab as an effective long-term treatment in pediatric patients with severe persistent allergic asthma.