Therapeutic Effect of Omalizumab in Severe Asthma: A Real-World Study in Korea

Abstract

PurposeOmalizumab, an anti-immunoglobulin E (IgE) monoclonal antibody, has proved to be effective for the treatment of severe asthma. However, there is no direct evidence of effectiveness of omalizumab in Korean patients with severe asthma. We sought to evaluate the real-world effectiveness of omalizumab in Korean adult patients suffering from severe asthma and to identify predictors of favorable response.MethodsA retrospective analysis of electrical medical records was performed on severe allergic asthmatic patients with omalizumab treatment group (OT group) for more than 6 months between March 2008 and February 2016. Propensity score matching was applied to define the standardized treatment control group (STC group) treated without omalizumab. Asthma-related outcomes were compared between the 2 groups, and analyzed before and after omalizumab use in the OT group. Responders to treatment were defined as patients showing >50% reduction in asthma exacerbations and/or systemic steroid requirement during the outcome period.ResultsOne hundred twenty-four patients with severe asthma (62 in the OT group; 62 in the STC group) were enrolled in the study. Proportion of patients having the reduction of asthma exacerbation (53.2% vs 35.5%, P=0.015) and the rate of responders (67.7% vs 41.9%, P=0.007) were significantly higher in the OT group than in the STC group. Significant reductions were noted in asthma exacerbation (P=0.006), hospitalization (P=0.009), hospitalization days (P=0.006), systemic corticosteroid requirements (P=0.027), and sputum eosinophil count (P=0.031) in OT group compared with STC group. There were no significant differences in changes of forced expiratory volume in the 1 second (FEV1) levels between the 2 groups. No predictors of responders were found for omalizumab treatment.ConclusionsOmalizumab can reduce exacerbations/hospitalization/systemic steroid burst in Korean adult patients with severe asthma.

Is Omalizumab a Problem-Solving Remedy in Severe Asthma?

“… 10 Another report showed a significant reduction in FcεRI expression on basophils and dendritic cells, an overall increase in FEV1 with statistical significance, and a trend toward improvement in GETE and asthma exacerbation rate in nonatopic asthmatic patients treated with omalizumab. 11 In the work of Lee et al, 6 the rate of exacerbation, hospitalization, hospitalized days, and mean daily requirement of SCS were not significantly different between atopic and non-atopic patients in the OT group. However, the fact that a significant proportion of patients (30% of the OT group) showed no benefits from omalizumab treatment also emphasizes the need for more clarified and detailed criteria for selecting candidates for omalizumab treatment.…”

“…In this issue of the AAIR journal, Lee et al 6 have confirmed the real-world effectiveness of omalizumab in Korean patients with severe asthma for the first time. In contrast to previous real-world studies, their outcomes were compared between patients treated with omalizumab for 6 months (OT group) and control patients treated with standard treatment alone who were defined by propensity score matching, and changes in outcomes were also compared between the baseline and outcome periods within and between groups.…”

“…The real-world effectiveness would differ from those of prospective randomized controlled clinical trials. Thus, the results presented in the work of Lee et al 6 provide us practically valuable information on omalizumab treatment in Korean patients with severe asthma regardless of baseline clinical and socioeconomic characteristics.…”

“… 13 Recently, fractional exhaled nitric oxide , blood eosinophil, and serum periostin have been suggested as biomarkers for predicting omalizumab responders. 8 However, no definite predictors for favorable responses were identified in the work of Lee et al 6 More studies are needed to support extended use of omalizumab in nonatopic asthmatic patients. Further development of biomarkers and characterization of phenotypes that can predict responsiveness of omalizumab are mandatory.…”

“…Although 6 months of treatment might be not long enough to fully evaluate omalizumab effects, the mean reduction rate of 46% exacerbation and the responder proportion of 68%, which were similar to those of previous real-world studies, 7 8 were observed in the OT group. 6 Omalizumab effectively reduced the number of asthma exacerbations, hospitalization, hospitalized days, the mean daily requirement of systemic corticosteroid (SCS) per person, and sputum eosinophil without obvious adverse events in Korean patients. The results of real-world study are useful in that patients with severe asthma often have multiple comorbidities and different socioeconomic statuses which can affect outcomes of omalizumab treatment.…”