Benralizumab efficacy and safety in severe asthma: A randomized trial in Asia

Background: Benralizumab is indicated as add-on therapy in patients with uncontrolled, severe eosinophilic asthma; it has not yet been evaluated in a large Asian population with asthma in a clinical trial. Objective: To evaluate the efficacy and safety of benralizumab in patients with severe asthma in Asia. Methods: MIRACLE (NCT03186209) was a randomized, Phase 3 study in China, South Korea, and the Philippines. Patients aged 12–75 years with severe asthma receiving medium- to high-dose inhaled corticosteroid/long-acting β₂-agonists, stratified (2:1) by baseline blood eosinophil count (bEOS) (≥300/μL; <300/μL), were randomized (1:1) to benralizumab 30 mg or placebo. Endpoints included annual asthma exacerbation rate (AAER; primary endpoint), change from baseline at Week 48 in pre-bronchodilator (BD) forced expiratory volume in 1 s (FEV1 is being defined, not BD, which has already been defined) and total asthma symptom score (TASS). Safety was evaluated ≤Week 56. Results: Of 695 patients randomized, 473 had baseline bEOS ≥300/μL (benralizumab n = 236; placebo n = 237). In this population, benralizumab significantly reduced AAER by 74% (rate ratio 0.26 [95% CI 0.19, 0.36], p <0.0001) and significantly improved pre-BD FEV₁ (least squares difference [LSD] 0.25 L [95% CI 0.17, 0.34], p <0.0001) and TASS (LSD −0.25 [−0.45, −0.05], p = 0.0126) versus placebo. In patients with baseline bEOS <300/μL, there were numerical improvements in AAER, pre-BD FEV₁, and TASS with benralizumab versus placebo. The frequency of adverse events was similar for benralizumab (76%) and placebo (80%) in the overall population. Conclusions: MIRACLE data reinforces the efficacy and safety of benralizumab for severe eosinophilic asthma in an Asian population, consistent with the global Phase 3 results.