Eosinophil (EOS) -associated type 2 inflammation is a common treatable feature during acute exacerbations of bronchial asthma and chronic obstructive pulmonary disease (COPD). To compare the clinical efficacy of standard prednisolone treatment, benrelizumab (humanized IL-5R α monoclonal antibody), or a combination of both in such patients with increased EOS. Methods: The ABRA study is a phase II, double-blind, double-dummy, active placebo-controlled clinical randomized trial. Adult patients with bronchial asthma or acute exacerbation of COPD (peripheral blood EOS ≥300/μ L) from the emergency departments of 2 hospitals, including Oxford University Hospital, UK, were randomly assigned at a ratio of 1:1:1 to receive the following treatment regimen: prednisolone 30 mg orally, once/d, for 5 consecutive days, combined with a single 100 mg benrelizumab subcutaneous injection (combination group); placebo tablets once a day for 5 consecutive days in combination with a single 100 mg subcutaneous injection of benrelizumab (BENRA group); Prednisolone 30 mg orally, once a day for 5 consecutive days, in combination with a single placebo subcutaneous injection (PRED group). The randomization process is performed through a centralized interactive computer system. All patients participating in data collection and study team members remained blinded to blood test results and treatment regimen assignment. The primary endpoints were the proportion of treatment failures (including death, hospitalization, need for systemic glucocorticoids or antibiotics for retreatment) within 90 days and the total visual analogue scale (VAS) symptom score at day 28 in the combined relizumab group compared to the prednisolone alone group and were analyzed in the intention-to-treat population. The trial is registered on Clinicaltrials.gov as NCT04098718.
