Clinical Characteristics of Responders and Non-Responders: Experience Following Four Years of Benralizumab Therapy

Introduction: Long-term outcomes for Benralizumab, a monoclonal antibody targeting IL-5, in severe asthma are limited, with little data differentiating responders from non-responders. We describe characteristics and outcomes of patients started on benralizumab at our asthma centre. Methods: Data was collected for patients who commenced Benralizumab in 2018/19. Responder/non-responder differentiation was based on continuation of therapy at four years. Data were collected on baseline characteristics including co-morbidities, physiological parameters (FEV1 % predicted, peripheral eosinophil count, FeNO, exacerbation rate), and self-rated asthma questionaires. Results: Of 52 patients started on Benralizumab, 36 (69%) remained on therapy after four years [Responders], and 16 (31%) stopped due to inefficacy [Non-responders]. Responders demonstrated sustained treatment benefit after four years with significant reductions in exacerbation frequency and daily oral corticosteroid use compared with non-responders. There were no significant differences in physiological parameters or baseline demographics between the two groups. Non-responders were statistically more likely to have Breathing Pattern Disorder (BPD) (p<0.01). 15/16 of non-responders stopped Benralizumab after less than 12 months. 8 non-responders were trialled on a further biologic (dupilumab n=4, omalizumab n=2, reslizumab n=1), of whom 75% continued treatment. Conclusion: Benralizumab responders have improved asthma control, reduction in exacerbations and OCS use that persists after four years of treatment. Non-responders had significantly higher rates of co-existing BPD, highlighting the importance of MDT team assessment.