Benralizumab Reduces Asthma Exacerbations and Costs Among Medicare Beneficiaries with Severe Asthma: The ZEPHYR-5 Study

Purpose: Clinical trials have demonstrated benralizumab reduces exacerbations among patients with severe asthma. Evidence on the effectiveness of benralizumab among older adults is limited. The objective was to assess the change in the annual asthma exacerbation rate (AAER), exacerbation-related medical costs, and asthma medication utilization 12 months before and after the initiation of benralizumab in Medicare patients, as well as in an all-payer sample, in a subgroup with prior biologic use, and segmented by benralizumab adherence status. Methods: This was a single-arm, 12-month pre-/post-, within-subjects study using 2017– 2023 MORE 2 Registry ® and Medicare Fee-For-Service databases. Included patients met the following criteria: 1) prescription for benralizumab (index date) and ≥ 1 refill within 90 days, 2) 12 months of database enrollment preceding and following the index date, 3) ≥ 1 inpatient or ≥ 2 outpatient claims with a diagnosis of asthma during the baseline period, and 4) ≥ 2 asthma exacerbations during the baseline period. Outcomes included percent change in AAER, exacerbation-related medical costs, and asthma medication utilization. Results: The study included 4,611 Medicare patients and 7,706 patients in the all-payer sample. Among Medicare patients, there was a 43.5% reduction in AAER (mean [SD], 3.8[2.0] to 2.2[2.2] exacerbations per year; P < 0.001). Exacerbation-related medical costs decreased across all cost categories, as did use of corticosteroids and other asthma medications. Reductions in outcomes were also observed in an all-payer sample. Conclusion: Medicare patients with severe asthma initiating benralizumab demonstrated meaningful reductions in AAER, exacerbation-related medical costs, and corticosteroid use in a real-world setting. Keywords: asthma, exacerbation, benralizumab, biologics, effectiveness