A comparison of the impact of anti-IL5/5r therapies in allergic versus non-allergic patients with severe eosinophilic asthma in a real-life setting.

Objective: This study aimed to compare the clinical characteristics and treatment outcomes of allergic patients (AP) and non-allergic patients (NAP) with severe eosinophilic asthma (SEA) treated with anti-IL5/IL5R biologic agents (mepolizumab, benralizumab, or reslizumab) over one year. Sub-analyses assessed treatment response variations between AP and NAP based on the biological used and compared outcomes among AP with and without fungal allergy.

Methods: Observational retrospective analysis. Clinical characteristics, laboratory findings, pulmonary function tests, Asthma Control Test (ACT) scores, oral corticosteroid (OCS) usage, and exacerbation frequency were assessed at the initiation of biological treatment and after one year.

Results: Sixty-five patients with SEA were included, 41 AP and 24 NAP. 55.4% were treated with mepolizumab, 33.8% with benralizumab, and 10.8% with reslizumab. Before anti-IL5/5R treatment, AP had worse baseline outcomes but there were no differences in pulmonary function. Mean annual exacerbation rate and percentage of patients requiring OCS and dose of prednisone were higher in AP than NAP. AP had significantly higher total IgE values. After one year of treatment, more AP discontinued OCS than NAP (p = 0.025). Both experienced a significant reduction in exacerbation frequency (p = 0.001) and improved respiratory function. 70.7% of AP and 60% of NAP improved ACT ≥3 points. There was no significant difference between AP and NAP using mepolizumab (p = 0.145) or benralizumab (p = 0.174) in reducing OCS.

Conclusions: Anti-IL5/IL5R reduced the need for OCS and improved asthma control, regardless of allergic status. Fungal allergy led to lower ACT scores and higher exacerbations than other allergens; both groups improved with anti-IL5/ILR.