Objectives: The aim of this study was to assess the stability of the effectiveness of omalizumab as add-on treatment in 11 patients with severe persistent allergic asthma followed for 4 years. Secondary outcomes were safety and economic impact, in terms of use of healthcare resources.
Methods: This retrospective study was designed to analyse a series of patients with severe allergic asthma treated with omalizumab. Patients were initially enrolled as part of the CIGE025A2425 international multicentre clinical trial. At the end (week 32), 11 responsive patients went on to complete the study and continued omalizumab treatment until June 2010. The monitoring visits coincided with the timescales planned for administering the drug and for the follow up. To estimate the economic impact, the PRE-POST treatment comparison was obtained by comparing the annual pretreatment costs with an annual average of the 4-year posttreatment period costs
Results: After 4 years, 81.8% of patients showed a good/excellent Global Evaluation of Treatment Effectiveness scale score and 81.2% showed an excellent increase (>1.5) in the Asthma Quality of Life Questionnaire score. The average forced expiratory volume in one second (FEV(1)) at 4 years was 75.3% compared with the predicted normal value for each patient, with a net increase (p = 0.009) compared with baseline FEV(1) values (58.6%). The frequency of serious exacerbations dropped by 94.7% compared with the pretreatment period, while mild-moderate exacerbations fell by 41.8%. A reduction in costs was observed for hospital admissions (97.3%), visits to emergency department (ED) (97.5%) and mild-moderate exacerbations (84%). The average cost reduction of concomitant drugs remained at 36%.
Conclusions: This study confirms the effectiveness and reliability of omalizumab over the long term, while providing an excellent safety profile. The additional cost due the use of omalizumab was offset by the medium- and long-term savings associated with the reduction in hospital admissions and access to ED.