Background Omalizumab is a humanised monoclonal antibody manufactured by recombinant DNA technology. It is indicated as an add-on therapy to improve asthma control in patients with severe persistent allergic asthma with forced expiratory volume in 1 s(FEV₁) <80%.

Purpose To evaluate the effectiveness of omalizumab (Xolair) in asthmatic patients treated with this drug in a tertiary hospital during 2015.

Material and methods This was an observational retrospective study of patients treated for asthma with omalizumab during 2015 in a tertiary hospital. Data were obtained by Farmatools and Drago AE programmes. All patients treated with omalizumab for at less 1 year were included. Clinical variables collected were: FEV₁(RD >80%), serum total level of IgE (RD <100 UI/mL) and omalizumab dose. Effectiveness was evaluated by number of emergency department visits for asthma.

Results 66 patients were included in the study with a mean age of 37 years (40 women, 26 men). 94% of patients did not require emergency visits for asthma. At the start of the study, they presented mean serum levels of IgE of 1702 UI/mL; during this period, a mean decreased of 47% was observed. However, at the end of the study period, we observed increased serum levels of IgE in all patients. For FEV₁, at the end of study, we found that: 17% of patients had FEV₁ <60%, 57% had FEV₁ 60–80% and FEV₁ was >80% for the rest of the patients. As omalizumab is indicated in patients diagnosed with persistent allergic asthma, we should consider discontinuing treatment in patients with FEV₁ <80% .

Conclusion Omalizumab was highly effective in this study, similar or even better than the effectiveness showed in clinical trials. We observed that lower baseline total IgE was associated with less effective treatment.

References and/or acknowledgements Technical data for omalizumab.

No conflict of interest