Real-world study in severe eosinophilic asthma patients refractory to anti-IL5 biological agents treated with benralizumab in Spain (ORBE study)

BACKGROUND: Benralizumab, a monoclonal antibody targeting the human interleukin-5 (IL-5) receptor (IL-5R), was used before marketing authorisation in Spain in a real world setting as part of an early-access programme (EAP) to treat patients with severe eosinophilic asthma with prior insufficient response or intolerance to anti-IL5 treatment (mepolizumab or reslizumab). The objective of this study is to describe the patient profile candidate for treatment and to assess benralizumab effectiveness. METHODS: This is an observational, retrospective, multicentre study in severe eosinophilic asthma patients refractory to other biological agents targeting the IL-5 pathway. Baseline characteristics included closest data, from the previous 12 months, to benralizumab treatment onset (index date). Patients were followed until the last treatment dosage while EAP was active (March to December 2018). Effectiveness was evaluated versus baseline, in patients who received at least three doses, with asthma control test (ACT), Mini Asthma Quality of Life Questionnaire (MiniAQLQ), annual severe exacerbation rate, oral corticosteroids treatment (OCS) and asthma-related healthcare resources utilization. RESULTS: Twenty-seven patients treated with benralizumab were included in the analysis. Effectiveness was assessed in 19 patients. Both questionnaires showed clinically meaningful differences, i.e. ACT score ≥ 3 and MiniAQLQ score ≥ 0.5, compared with baseline [mean (SD), 3.3 (6.8) and 1.2 (1.9), respectively]. Patients treated with OCS decreased during follow-up from 88.9% (n = 24/27) at baseline to 78.9% (n = 15/19) and 31.6% (n = 6/19) had an OCS dose reduction ≥ 50%. The difference in annual severe exacerbation rate during follow-up showed a significant reduction vs. baseline (2.12 per patient-year, 95% CI 0.99–3.24, p = 0.002). The differences in annual rate of non-scheduled primary care and specialist visits during follow-up indicated a significant decrease [2.28 per patient-year (95% CI 1.55–3.01; p < 0.001) and 1.47 per patient-year (95% CI 0.65–2.30; p = 0.004), respectively], as well as the difference in annual rate of number of emergency department visits [1.18 per patient-year (95% CI 0.51–1.85; p = 0.007)]. CONCLUSIONS: These results suggest that severe eosinophilic asthma patients receiving benralizumab, presented clinically meaningful improvement in asthma control and asthma-related QoL as well as OCS dose reduction. Results also aim to significant reductions in annual severe exacerbation rates, non-scheduled primary care and specialist visits, and emergency department visits rates.