Chronic obstructive pulmonary disease (COPD) is a heterogeneous disease that is entering a new era in precision medicine. Advances in disease endotyping have challenged the traditional view of COPD as a uniformly neutrophilic disorder and revealed biologically distinct subgroups in whom targeted immunomodulation may be effective. Reproducible signatures of type 2 (T2) inflammation and epithelial-derived alarmin activation have emerged as actionable pathways, reshaping therapeutic development in COPD. This narrative review synthesises mechanistic insights and clinical trial evidence for biologic therapies targeting key T2 cytokines such as interleukin-5 (IL-5) IL-4/IL-13 and upstream epithelial alarmins, including interleukin-33 (IL-33) and thymic stromal lymphopoietin (TSLP). We examine why earlier approaches targeting neutrophilic inflammation failed, and how biomarker-driven trial design has enabled success in selected populations. Across these programmes, therapeutic efficacy has depended not only on the pathway targeted but also on patient selection, disease stage and timing of intervention. We propose that the future of biologics in COPD lies in integrating biomarkers, treatable traits and longitudinal phenotyping to align the right patient with the right pathway at the right time, closing persistent treatment gaps in this common, overlooked and burdensome disease.
Finney et al. (Mon,) studied this question.