Effectiveness of omalizumab in patients with inadequately controlled severe persistent allergic asthma: an open-label study

Abstract

Background: In a 1-year, randomized, open-label study in patients with moderate-to-severe allergic (immunoglobulin E (IgE)-mediated) asthma, adding omalizumab to best standard care (BSC) significantly improved efficacy outcomes compared with BSC alone (control). We assessed the efficacy of omalizumab in the subgroup of patients with inadequately controlled severe persistent allergic asthma despite high-dose inhaled corticosteroids (ICS) plus a long-acting beta(2)-agonist (LABA), which reflects the European Union (EU) label population.

Methods: Efficacy outcomes included annual asthma exacerbation rate, annual asthma deterioration-related incident (ADRI) rate, % predicted forced expiratory volume in 1 s (FEV(1)), asthma symptoms (Wasserfallen score) and quality of life (Mini Asthma Quality of Life Questionnaire (Mini-AQLQ)), which were compared in the omalizumab and control groups. Outcomes were also determined for omalizumab-treated patients judged to have responded to therapy (> or = 0.5-point improvement in Mini-AQLQ overall score at 27 weeks).

Results: In total, 164 patients (omalizumab, n=115; control, n=49) were receiving high-dose ICS plus a LABA. Annual asthma exacerbation rate was significantly reduced by 59% in the omalizumab group vs. control (1.26 vs. 3.06; P<0.001). ADRI rate was significantly reduced by 40% in the omalizumab group compared with control (5.61 vs. 9.40; P<0.05). Significant improvements were also seen in % predicted FEV(1) (71% vs. 60%; P<0.001), change from baseline in asthma symptom scores (-6.7 vs. 0.5; P<0.05) and Mini-AQLQ overall score (1.32 vs. 0.17; P<0.001). In omalizumab-treated patients, 71/102 (70%) were judged to have responded to therapy. In these Mini-AQLQ-assessed responders, exacerbation rate was reduced by 64% vs. control (1.12 vs. 3.06; P<0.001), ADRI rate was reduced by 50% vs. control (4.71 vs. 9.40; P<0.01). Percent predicted FEV(1) (73% vs. 60%; P<0.001), change from baseline in asthma symptom scores (-8.1 vs. 0.5; P<0.001) and Mini-AQLQ overall score (1.81 vs. 0.17; P<0.001) were also further significantly improved vs. control.

Conclusions: Adding omalizumab to BSC is efficacious in patients with inadequately controlled severe persistent allergic asthma despite high-dose ICS plus a LABA (EU label population), with further efficacy observed in patients judged to have responded to therapy which may more accurately illustrate the actual benefit of omalizumab therapy in clinical practice. The naturalistic setting of this study confirms the benefits observed in double-blind randomized clinical trials.