Omalizumab in allergic bronchopulmonary aspergillosis (ABPA): A systematic review and meta-analysis

An unmet clinical need exists in the management of treatment-refractory allergic bronchopulmonary aspergillosis (ABPA). Omalizumab has shown promising effects in case series and cohort studies; however, evidence to support its routine clinical use is lacking.The aim of this systematic review and meta-analysis was to evaluate the clinical effectiveness and safety of omalizumab in patients with ABPA.A systematic search across standard databases was conducted using specific keywords until May 13, 2021. A meta-analysis was performed to compare the effectiveness (exacerbations, oral corticosteroid [OCS] use, lung function, patient-reported asthma control) and safety of pre- and post- omalizumab treatment. Subgroup analyses were performed for treatment duration and underlying disease.In total, 49 studies (n=267) were included in the qualitative synthesis and 14 case series (n=186) in the quantitative meta-analysis. Omalizumab treatment significantly reduced the annualized exacerbation rate versus pre-treatment (mean difference [MD]: -2.09 [-3.07; -1.11], P0.01). There was a reduction in the OCS use (risk difference [RD]: 0.65 [0.46;0.84], P0.01), an increase in termination of OCS use (RD: 0.53 [0.24;0.82], P0.01), and a reduction in OCS dose (mg/day) (MD: -14.62 [-19.86; -9.39]; P0.01) in ABPA patients receiving omalizumab. Omalizumab improved forced expiratory volume in 1 second (FEV1) % predicted by 11.9% (8.2; 15.6, P0.01) and asthma control, and was well tolerated.Omalizumab treatment reduced exacerbations and OCS use and improved lung function and asthma control in patients with ABPA and was well tolerated. The results highlight the potential role of omalizumab in the treatment of ABPA.