The treatment of severe asthma has been transformed by biologics targeting type 2 inflammation, and choosing among them is now guided by biomarkers (blood eosinophils, FeNO, IgE) and comorbidities. The anti-IL-5 agents mepolizumab and reslizumab, and the anti-IL-5-receptor agent benralizumab, each reduce exacerbations by roughly half and lower oral corticosteroid use in eosinophilic asthma. Dupilumab, which blocks the IL-4 receptor alpha (and thus both IL-4 and IL-13 signaling), produces among the largest improvements in lung function and helps the type 2 phenotype broadly. Tezepelumab, an anti-TSLP antibody acting upstream, is notable for working across phenotypes — including patients with lower eosinophil counts who respond poorly to the other agents — giving it the broadest applicability.
The newest development is depemokimab, an ultra-long-acting anti-IL-5 antibody engineered for dosing just twice a year. Its positive Phase 3 program (SWIFT-1 and SWIFT-2) showed reduced exacerbations, and it reached approval in 2025 — a meaningful convenience advance for maintenance therapy.
Further reading: comparative biologic efficacy network meta-analyses (Nopsopon et al. and Akenroye et al., JACI 2022–2023); tezepelumab NAVIGATOR (Menzies-Gow et al., NEJM 2021); depemokimab SWIFT-1/2 (NEJM 2024).