Long-Term Effectiveness of Anti-IL-4R Therapy Following Suboptimal Response to Anti-IL-5/5R Therapy in Severe Eosinophilic Asthma

BACKGROUND: Dupilumab is an anti-IL-4R monoclonal antibody (mAb) with proven ef fi cacy in severe eosinophilic asthma (SEA). A suboptimal response to anti-IL-5/5R mAbs is seen in some patients with ongoing evidence of type 2 (T2) in fl ammation. OBJECTIVE: To understand whether targeting IL-13 pathways with dupilumab in these patients may lead to better clinical outcomes. METHODS: We performed a retrospective analysis of the extended clinical effectiveness of dupilumab up to 2 years of treatment in patients with SEA who had not responded adequately to anti-IL-5/5R biologics. The ability to achieve clinical remission and the change in the remission domains of exacerbation rate (AER), maintenance oral corticosteroid dose (mOCS), lung function (forced expiratory volume in 1 second), and asthma control (Asthma Control Questionnaire 6) were recorded. RESULTS: Thirty-seven patients (mean age 41 years, 70% female) were included in the analysis. The mean (standard deviation) AER fell by almost 90% from 3.16 (1.28) at dupilumab initiation to 0.35 (0.72) after 1 year. The median (interquartile range) mOCS dose (n [ 20) fell from 10 (5-25) mg to 0 (0-5) mg at 1 year, with 14 of 20 (70%) able to stop prednisolone altogether. Clinical remission was achieved in 16 of 37 (43%). Patients who achieved remission had a higher preIL-5/5R fractional exhaled nitric oxide (FeNO) level (85 [39198] parts per billion [ppb] vs 75 [42-96] ppb, P [ .03). CONCLUSIONS: Signi fi cant improvements in clinical outcomes are possible after a switch to dupilumab in patients experiencing a suboptimal response to anti-IL-5/5R therapies. A higher FeNO in poor responders to anti-IL-5/5R who achieve remission with dupilumab is suggestive of an IL-13-driven subphenotype of T2-high asthma in which the eosinophil appears unlikely to play a key role in the disease pathogenesis. (c) 2024 American Academy of Allergy, Asthma & Immunology (J Allergy Clin Immunol Pract 2024;12:1794-800)