Aims: To evaluate whether the treatment with benralizumab may lead to prolonged clinical response up to 96 weeks.

Methods: A post-hoc analysis was conducted on patients enrolled in the ANANKE study. Evaluable patients were classified as long-term responders if they achieved any of the following: zero exacerbations; zero maintenance oral corticosteroids (OCS) use; ACT score >= 20 (well-controlled asthma) at 4 weeks, maintaining the status until 96 weeks.

Results: 162 patients were evaluable after 96 weeks of follow up, of which 130 (80.2%) were long-term responders. At index date (benralizumab initiation), 79 (60.8%) were females and 35 (28.5%) were current or previous smokers. Median (IQR) duration of asthma was 14.9 (8.5 ? 26.4) years. Median blood eosinophil count and IgE count were 600.0 (440.0?900.0) cells/mm3 and 198.5 (91.5?475.6) IU/mL, respectively. Current or past nasal polyposis was observed in 77 (59.2%) patients. In the year prior to index date (baseline) the annualized exacerbation rate (AER) was 4.07 and the severe AER was 0.89. After 96 weeks, the AER decreased to 0.06 (-98% vs baseline). No severe exacerbations occurred in long term responders (-100% reduction vs baseline). 28 long-term responders were on OCS treatment at index date and 20 (71.4%) achieved dose reduction at 96 weeks; 18 (64.3%) patients eliminated OCS. ACT total score improved from a mean (SD) of 15.2 (4.5) at index date up to a mean (SD) of 21.8 (3.7) after 96 weeks.

Conclusions: After 96 weeks of treatment with benralizumab, the majority of patients achieved durable response. Among the outcomes observed, the most remarkable was the almost complete reduction of total and severe exacerbations.