Use of CompEx in eosinophilic patients with severe, uncontrolled asthma on benralizumab.

BACKGROUND: CompEx Asthma, a composite end-point for asthma exacerbations, captures clinically relevant, diary-based acute worsening events (AWEs) (defined as deterioration in daily peak expiratory flow concurrent with deterioration in asthma symptoms and/or rescue therapy use) and severe exacerbations (SevEx) (defined by American Thoracic Society/European Respiratory Society guidelines). We hypothesised that CompEx and SevEx would show similar benralizumab treatment effects and correlations to blood eosinophil counts in patients with severe asthma.

METHODS: This post hoc analysis of pooled 12-month data from two phase 3 studies included patients aged ≥16 years with severe, uncontrolled asthma who were randomised to benralizumab 30 mg or placebo. Annualised event rates were analysed using a negative binomial model. The impact of blood eosinophil count on treatment effect was assessed.

RESULTS: Among patients with a blood eosinophil count ≥300 cells·µL-1 (n=913), benralizumab reduced the annualised event rate versus placebo for CompEx (1.57 versus 2.57; risk ratio 0.61, 95% CI 0.53-0.70, p<0.001), SevEx (0.94 versus 1.55; risk ratio 0.60, 95% CI 0.52-0.70, p<0.001) and AWE (0.92 versus 1.57; risk ratio 0.59, 95% CI 0.48-0.72, p<0.001), with greater treatment effects observed for higher blood eosinophil counts. In patients with blood eosinophil count ≥300 cells·µL-1 , benralizumab was associated with shorter median event duration (CompEx: 10.5 days versus 17.0 days; SevEx: 10.0 days versus 15.0 days; AWE: 5.0 days versus 6.0 days).

CONCLUSIONS: Benralizumab reduced the risk of CompEx events with treatment effects similar to those for SevEx and AWEs across a range of blood eosinophil counts. Use of CompEx supports the evaluation of benralizumab and other novel drugs in clinical studies.